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THE
INSTITUTIONS
OF
PHYSIOLOGY.

[[i]] [[ii]]
[titlePage_recto]
THE
INSTITUTIONS
OF
PHYSIOLOGY

TRANSLATED FROM THE LATIN OF THE THIRD AND
LAST EDITION,
AND SUPPLIED
WITH COPIOUS NOTES,
BY
JOHN ELLIOTSON, M.D.
ASSISTANT PHYSICIAN TO ST. THOMAS’S HOSPITAL;
Of Jesus College, Cambridge; the Royal College of Physicians; the Medico-Chirurgical
Society; Honorary Member of the Physical Society of Guy’s Hospital;
and formerly President of the Royal Medical Society
of Edinburgh.

THIRD EDITION, CONSIDERABLY IMPROVED.

Quaeramus optima, nec protinus se offerentibus gaudeamus;
adhibeatur judicium inventis, dispositio probatis.
(Quintilian.)

London:
PRINTED FOR BURGESS AND HILL, MEDICAL BOOKSELLERS,
55, Great Windmill Street, Haymarket;
HODGES AND M’ARTHUR, DUBLIN; AND
ADAM BLACK, EDINBURGH.

1820.
[titlePage_verso]
J. Barker, Printer,
4, Crane Court, Fleet Street.

[[v]]

TO
HIS ROYAL HIGHNESS
PRINCE AUGUSTUS FREDERICK
DUKE OF SUSSEX,
EARL OF INVERNESS,
Baron of Arklow,
KNIGHT OF THE MOST NOBLE ORDER OF THE GARTER,
&c. &c. &c. &c.

THE STRENUOUS SUPPORTER OF EVERY THING WHICH CAN
EXALT THE CHARACTER OR AUGMENT THE
HAPPINESS OF MANKIND,
AND
THE FRIEND OF PROFESSOR BLUMENBACH,
THE FOLLOWING PAGES
ARE,
WITH HIS ROYAL HIGHNESS’S PERMISSION,
MOST RESPECTFULLY INSCRIBED.

[[vi]]

THE TRANSLATOR’S
PREFACE.

[[vii]]

In expressing the gratification which I must feel
at a third edition of my Work being so soon re-
quired, I have also to express my regret that
peculiar circumstances have compelled me to
leave it so many months out of print.

The Translation will be found revised, innu-
merable errors of various descriptions corrected,
every accession of physiological knowledge up
to the present moment inserted, several points
fully discussed which before were too briefly
noticed, and consequently the amount of my
Notes very considerably increased.

Many inadvertencies will no doubt still be dis-
covered, and so far from being displeased I shall
be grateful to have them pointed out, as well as
to have my opinions freely examined. For I
should blush to be reluctant in allowing to others
what I always claim myself, – sentire quae velim,
[Seite viii] et dicere quae sentiam.
Truth is my object, and,
though I have become a writer, my disposition
is really discere libentius quam dicere.

The lapse of ten years since the last publi-
cation of Professor Blumenbach’s work, no less
than since that of M. Richerand’s, has compelled
me to supply notes of correction as well as of
addition, and will excuse me for differing on
some points from my celebrated and venerable
author, without urging what is universally al-
lowed, – that, when a dwarf gets on the shoul-
ders of a giant, he may see farther than the giant
himself.

Whatever is peculiar and excellent in M. Ma-
jendie’s Physiological work, has been carefully
transferred, so that my readers will, I trust, pos-
sess not only a full and faithful statement of the
Physiological Science of the present time, but
enjoy the advantage of a sort of triple work by a
German, a Frenchman, and an Englishman.

15, Grafton Street, Bond Street,
April 8, 1820.

THE AUTHOR’S PREFACE
to the
LAST EDITION.

[[ix]]

Whenever my booksellers have informed me
that a new edition of any of my works was re-
quired, I have always gladly seized the opportu-
nity of correcting inaccuracies arising either from
carelesness or the imperfections of human nature,
and of adding in some places and altering in
others; in short, of sending forth the production
of my abilities in a more finished state.

In preparing this new edition of my Institu-
tions
of Physiology for the press, the same
anxious wish has been considerably heightened by
the importance of the subject, and by the appro-
[Seite x] bation evidently bestowed upon the last edition,
from its translation into our own language, into
Spanish, French, English,* Dutch, and Russian;
not to mention other proofs of its favourable
reception. I have endeavoured, therefore, to
enrich it not so much with an addition of pages,
as of various matter; to arrange the heads in a
more natural order; and to render the whole as
useful to students as possible.

September 10, 1810.

THE AUTHOR’S PREFACE
to the
FIRST EDITION.

[[xi]]

The same considerations which led Boerhaave,
and after him Haller, to write their Compendiums
of Physiology, induced the Author to compose
these Institutions.

The former says, ‘“that a teacher succeeds bet-
ter in commenting upon his own thoughts, than
upon a work written by another: – that his doc-
trine will be clearer, and his language generally
animated,”’ &c.*

The latter, ‘“That, although he formerly used
Boerhaave’s work as a text-book, he afterwards
[Seite xii] lectured upon one written by himself, because
anatomy had been so improved since the time
of Boerhaave, as to have become almost a new
science.”’*

What Haller said at that period respecting ana-
tomy, will be allowed to apply much more forcibly
at present to physiology, by any one who consi-
ders the most important parts of the science, –
the principal purpose of respiration, animal heat,
digestion, the true nature and use of the bile, the
function of generation, &c.

More, therefore, must be ascribed to the age
than to the author, if in these Institutions, after
so many modern physiological discoveries, he
delivers doctrines more sound and natural than it
was in the power of his most meritorious pre-
decessors to deliver.

Whatever he can claim as his own, whether
really new or only presented in a new view,
[Seite xiii] will be easily discovered by the learned and im-
partial reader; especially from the notes, in which
he has treated some of these subjects rather more
minutely than, in the text, was compatible with
the conciseness of his plan.

He has been at great pains in arranging the
subjects, so that the sections might succeed natu-
rally and easily, and arise, as it were, one out of
another.

He has not quoted a dry farrago of books, but
a select number, in doing which, he has wished
both to point out to students some excellent au-
thors not commonly known, especially those who
have professedly treated on particular branches of
the subject, and to open, besides medical sources
of information, others not yet applied, he con-
ceives, to Physiology as they deserve.

His grand object has been to deliver, in a faith-
ful, concise, and intelligible manner, the princi-
ples of a science inferior in beauty, importance,
and utility, to no part of medicine, if the words
[Seite xiv] prefixed by the immortal Galen to his Methodus
Medendi,
are true, as they most certainly are: –
‘“The magnitude of a disease is in proportion to
its deviation from the healthy state; and the
extent of this deviation can be ascertained by him
only who is perfectly acquainted with the healthy
state.”’

CONTENTS.

[[xv]]

CORRIGENDA.

Page 34, last line, for E read F.
Page 49, last line, for ? mark !
218, for Ottomans read Ottomacs.
––– last line, for it read earth.

THE
INSTITUTIONS
OF
PHYSIOLOGY. SECT. I.
OF THE LIVING HUMAN BODY IN GENERAL.

[Seite 1]

1. In the living human body, regarded as a peculiar
organisation, there are three objects of consideration.*

The materials of its subsistence, afforded by the
fluids;

The structure of the solids, containing the fluids;

Lastly, and principally, the vital powers, by which
the solids are enabled to receive the influence of the
[Seite 2] fluids – to propel the fluids – and perform various other
motions; and which, as they, in a certain sense, con-
stitute the essence of the living machine in general, so
also are of very different orders – some being common
to animals and vegetables – some peculiar to animals
and intimately connected with the mental faculties.

2. But these three, although really distinct, and
therefore distinctly considered by us, are so closely
related in the living system, (the phenomena, conditions,
and laws of whose functions, in the healthy state, are
the object of physiology) that no one can be contem-
plated but in its relation to the rest.

For the materials of the body, although originally
fluid, are naturally disposed to become solid; and, on
the other hand, the solids, besides having been formed
from the fluids, abound, however dry they may appear,
in various kinds of fluid constituents, both liquid and
aëriform: lastly, it may probably be affirmed, that no
fibril, during life, is destitute of vital power.

3. We shall now examine each of these separately;
and first, the materials afforded by the fluids, which
form both the fundamental and most considerable por-
tion of our bodies.*

SECT. II.
OF THE FLUIDS IN GENERAL, AND PARTICULARLY
OF THE BLOOD.

[Seite 3]

4. The fluids of the body may be conveniently re-
duced to three classes.

A. The crude; viz. the chyle, contained in the primae
viae and destined to become blood; and matters ab-
sorbed on the surface and destined to be conveyed to
the chyle.

B. The blood itself.

C. Those secreted from the blood, whether inert and
excrementitious, like the urine; or intended for certain
purposes in the economy: the latter may be perma-
nently liquid, as the bile; or disposed to solidity, as
the osseous and other plastic juices.

5. Of the first and third of these classes we shall
hereafter speak, in treating of chylification, secretion,
and the other functions to which each fluid appertains.
At present our attention shall be devoted to the blood*
the chief and primary fluid – the vehicle of those suc-
cessions of oxygenous and carbonaceous particles,
which cease with life only – the nourisher of the frame
– the source of almost every fluid – that into which the
crude fluid is converted and from which all the secre-
tions are derived – and which, with the exception of
some exsangueous parts, as the epidermis, the arach-
noid, the amnion, &c. the vitreous substance of the
[Seite 4] teeth, the body of the crystalline lens, &c. is univer-
sally diffused through the system, in various propor-
tions, indeed, according to the various natures of the
similar parts, to use the language of the ancients,*
v.c. abundantly in the muscles and glands, sparingly
in the tendons and cartilages. (A)

6. The blood is a fluid sui generis, of a well known
colour and peculiar odour; its taste is rather saline
and nauseous; its temperature about 96° of Fahrenheit;
it is glutinous to the touch; its specific gravity, though
different in different individuals, may be generally esti-
mated as 1050, water being 1000; when fresh drawn,
and received into a vessel, it exhibits the following
appearances.

7. At first, especially while still warm, it emits a
vapour which has of late been denominated an animal
gas and shewn to consist of hydrogen and carbon, sus-
pended by caloric.§ This, if collected, forms drops
[Seite 5] resembling dew, of a watery nature, but affording a
nidorous smell, which is most remarkable in the blood
of carnivorous animals, peculiar and truly animal.
Much of this watery liquor still remains united with
the other parts of the blood. (B)

8. In the mean time the blood, when its temperature
has fallen to about 78°, begins to separate into two
portions. A coagulum is formed, from the surface of
which exudes, as it were, a fluid of a yellowish slightly
red colour, denominated serum: the more abundantly
this exudes, the greater is the contraction of the glu-
tinous coagulum, which has received the appellations
of crassamentum; and, from some resemblance to the
liver in colour and texture, of hepar sanguineum; of
placenta; and, from the circumstance of its being sur-
rounded by the serum, of insula. (C)

9. The crassamentum may, by agitation or repeated
ablution, be easily separated into two constituent
parts – the cruor, which imparted to the blood its
purple colour, and the lymph, which on washing is for-
saken by the cruor, and called, from its greater solidity,
the basis of the crassamentum. The stronger affinity
of the cruor for the lymph than for the serum, is proved
by the necessity of violence to effect their disunion.
By the removal of the cruor the lymph becomes gra-
dually paler, till it is at length merely a white tenacious
coagulum. (D)

10. Besides the watery fluid first mentioned, these
are the three constituents of the blood, viz. the serum,
the cruor, and the lymph: we shall presently treat of
each more particularly. These, however, while recent,
and in possession of their native heat, are intimately
[Seite 6] mixed, and form an equable, homogeneous fluid. Their
relative proportion is astonishingly diversified, accord-
ing to age, temperament, diet, and similar circum-
stances which constitute the peculiar health of each
individual.

11. The serum is a peculiar fluid, the chief cause of
the viscidity of the blood, and easily separable by art
into different constituent principles. If subjected to a
temperature of 150° Fahr. a portion is converted into a
white scissile substance, resembling boiled albumen:
the rest exhibits, besides the watery fluid so often men-
tioned, a turbid fluid of a gelatinous, or rather mucous,*
nature, which on cooling appears a tremulous coagu-
lum. The serum is remarkable for the quantity of soda
(mineral alkali) which it contains. (E)

12. The cruor has many peculiarities, in regard to
both the colour and the figure of its particles. It con-
sists of globules, which in recent blood are of a constant
form and size, and said to be 1/3300 of an inch in dia-
meter. Their form, indeed, has been a subject of dis-
pute; but I am disposed to consider it as much more
simple than some writers of great celebrity have ima-
gined. I have always found it globular, and could
never discover the lenticular shape which some have
asserted that they remarked.

It has been likewise advanced, that the globules
change their form, while passing through a vessel of
very small capacity – that, from being spherical, they
become oval; and, when they have emerged into a
[Seite 7] vessel of larger area, that they again resume their glo-
bular shape.* This, although I would by no means
deny it, I cannot conceive to occur during the tranquil
and healthy motion of the blood, but should refer it to
a spasm of the small vessels.

Their globular figure can be seen in a living animal
only, or in blood very recently drawn: for they are
soon unobservable, becoming a shapeless mass which
resembles serum in every circumstance excepting
colour.

13. Their colour is red, and from it is derived the
colour of the blood. In intensity it varies infinitely;
paler in animals which have been poorly nourished or
have suffered from haemorrhage; more florid, when
oxygenised (rendered arterial, to use the common
phrase) by exposure either to atmospheric air, or, more
especially, to oxygen; darker when carbonised, (in
common language, rendered venous) by exposure to
carbonic acid gas, or to hydrogen. The redness is
[Seite 8] most probably to be ascribed to the oxide of iron,* the
quantity of which, however, is so minute, that it has
been most variously estimated. (F)

14. The last constituent principle of the blood to be
noticed, is the plastic lymph, formerly confounded with
the serum. This has been called the basis of the cras-
samentum, the glutinous part, the fibre or fibrous matter
of the blood, and, like the caseous part of milk and the
gluten of vegetables, been discovered by late analysis
to abound in carbon and azote. (G)

15. It is properly denominated plastic, because it
affords the chief materials from which the similar
parts, especially the muscles, are immediately pro-
duced; nourishes the body throughout life; repairs
wounds and fractures in an extraordinary manner; fills
up the areae of large blood vessels when divided; and
forms those concretions which accompany inflamma-
tions, and that remarkable deciduous membrane found
in the recently impregnated uterus for the attachment
of the ovum.

16. Thus much have we said, respecting the consti-
tuent parts and nature of the blood, the most important
fluid of the animal machine, – a fluid, which excites the
heart
to contraction; which distributes oxygen to every
part, and conveys the carbon to the excretory vessels,
giving rise, by this change, to animal heat; which sup-
[Seite 9] plies the materials of the solids originally, and after-
wards their nourishment; and from which all the other
fluids,
with the exception of the crude (4.), are secreted
and derived. Of the multifarious importance of the
blood, we shall speak particularly hereafter.


NOTES.

(A) The blood is now known not to absorb any oxygen during
ordinary respiration. See note (C.) Sect. viii.

(B) When blood, venous or arterial, is placed in the vacuum
of an air-pump* or coagulates in the air, it emits a considerable
quantity of carbonic acid gas: in a paper lately read to the Royal
Society, but not yet printed, the quantity is said to be much
greater after a meal, and much less if the blood is buffy.

(C) Blood coagulates when cut off from communication with
the mass by escape from its vessels, whether warm or cold, in the
air or in vacuo, diluted or undiluted, at rest or in motion; whereas
within the vessels, rest, which causes a cessation of intercourse
between the motionless portion and the general mass, is in many
cases sufficient to effect its coagulation. After death from a blow
on the stomach, lightning, arsenic, hard running, &c. it does not
coagulate.

(D) To suppose any affinity of the red particles for either the
lymph or the serum is erroneous. Leeuwenhoek and Hartsoeker
long since proved that serum merely suspends them, for if, when
separated, they are triturated in some serum, part of them is
taken up and the serum assumes a red colour; but if the fluid is
allowed to settle in a cylindrical glass, they slowly precipitate
themselves to the bottom, and the serum above becomes clear,
as before. When blood is drawn, the serum easily separates on
the coagulation of the lymph. But the lymph coagulates before
[Seite 10] the colouring particles have time to fall to the bottom, and en-
tangling them acquires a red colour, forming the crassamentum:
if, however, the lymph coagulate slowly, as in the phlogistic
diathesis, the greater specific gravity of the cruor detaches it very
considerably from the lymph, which remains colourless above,
constituting what is called the inflammatory coat, crust, or buff.*
Berzelius even believes the lymph to be in a state of solution in
the serum, while the cruor is simply suspended in this solution;
but the separation of the serum in dropsy, vesication, &c. led
Mr. Hunter to a different conclusion.

(E) The coagulable part of serum is albumen; that which
remains fluid is called serosity, – a name given it by Cullen, and
contains no gelatine as the French chemists asserted, but an ani-
mal matter different from both gelatine and albumen, with a mi-
nute portion of albumen and fibrine, and affords a little free soda,
muriate, lactate, and phosphate, of soda, and muriate of potash,
with 905/1000 of water.§ If mixed with six parts of cold water,
serum does not coagulate by heat.

(F) When venous blood acquires a florid colour by exposure to
oxygen or atmospheric air, (and it does so even when covered by
a bladder) carbonic acid gas is formed, and an equal quantity of
oxygen gas disappears. If exposed to nitrous oxide, it becomes
of a brighter purple, and much of the gas is absorbed: carbonic
acid gas renders it darker and is a little absorbed, while azote
occasions no change. The dark colour produced in arterial blood
by carbonic acid or azotic gas takes place if blood is placed in
[Seite 11] vacuo, though less rapidly and deeply than if exposed to hydrogen
gas. Arterial blood left in contact with oxygen gradually acquires
the same dark colour, and no oxygen will afterwards render it
scarlet. Berzelius finds the colouring particles only concerned in
these changes, and, after all, no difference of composition can be
detected between scarlet and purple blood.

It has been generally supposed that iron exists in the red par-
ticles of the blood as a subphosphate. Berzelius informs us that
serum, although able to dissolve a small portion of the oxides,
not indeed of the phosphates, of iron, does not acquire a red
colour by their addition, and that he has never discovered iron nor
lime in the entire blood, although both are so abundant in its
ashes. He concludes that the blood contains the elements of
phosphate of iron and of lime, and of carbonate of lime, and also
of phosphate of magnesia, united in a manner different from their
combination in the salts.

Mr. Bauer, whose microscopic skill is effecting so much for
anatomy and physiology, finds that the globules consist of a
colourless nucleus and an enveloping coloured portion,* as Dr.
Young first discovered. A nucleus is about 1/5000 of an inch in
diameter, and the whole globule nearly one-fourth larger. In the
unpublished paper above quoted, it is further stated that Mr. Bauer
has discovered a third set of smaller colourless globules in the
blood, 1/2800 of an inch in diameter. They appear to belong to
the fibrine, and Sir Everard Home accordingly denominates them
lymph globules. Colourless globules gradually form also in se-
rum. Oxygen and hydrogen also exist in fibrine.

(G) The fibrine, albumen, and colouring matter, afford, on de-
composition, the same saline and gaseous products. Berzelius
views them all three as modifications of the same substance.
Albumen contains a greater proportion of oxygen than fibrine,
and has sulphur for a constituent part, which, however, cannot be
detected while the albumen is entire, any more than the iron while
[Seite 12] the cruor is entire. The chief differences between the colouring
matter and fibrine are, colour, the spontaneous coagulation of
fibrine at all temperatures while the colouring matter may be
dried without losing its solubility in water and becomes insoluble
only at a certain temperature, and the peculiarity in the latter of
not diminishing in volume like fibrine during exsiccation. Albu-
men is intermediate between the two, and its only character of
distinction from fibrine is that it does not coagulate spontaneously,
but requires a high temperature. The brain and crystalline lens are
a sort of albumen j the epidermis, nails, hair, horn, cartilage, are
nearly composed of it; of bone and muscle it is an essential part.
Fibrine exists in muscles only, besides the blood, and is indeed their
chief constituent, giving them form and rendering them fibrous.
Gelatine, or rather what becomes so by the agency of boiling water,
contains somewhat less carbon and more hydrogen than albumen,
and although not obtained from blood, is an important part of our
frame: the cutis, serous membranes, and tendons, are a species
of it, it forms the chief part of cellular membrane, and is an
essential constituent of bones, muscles, ligaments, hair, &c. The
composition of the substance of the viscera is not well known.

The blood of brutes has the same general character as our own,
but Berzelius finds a larger proportion of nitrogen in that of the
bull, and by analogy I should think there must be a peculiarity in
the blood of every species. Muscles look pretty much alike in
various animals, yet our dishes disclose the greatest diversities.
Transfusion, or pouring the blood of one system into another, has
been practised for a century and a half, and satisfies us that the
blood, whether arterial or venous, of one individual, agrees well
enough with another of the same species; but some late experi-
ments of Dr. Leacock,* and subsequently of Dr. Blundel, render
it unlikely, contrary to the opinion of former experimentalists,
that the blood of one species suits the system of another. Dr.
Young found the large outer globules of the skate to be oval.

SECT. III.
OF THE SOLIDS IN GENERAL, AND OF THE MUCOUS
WEB IN PARTICULAR.

[Seite 13]

17. The solids* are derived from the fluids. In the
first rudiments of the gelatinous embryo, they gradually
commence in their respective situations, and differ in-
finitely in their degrees of cohesion, from the soft and
almost pulpy medullary matter of the brain, to the
vitreous substance of the corona of the teeth.

18. Besides the gelatinous (11) and glutinous (15)
parts of the solids, earth enters more or less into their
composition, and is principally lime united with phos-
phoric acid. The bones possess this in the greatest
abundance, particularly in advanced age, whereas in
childhood the gelatinous matter abounds.

19. With respect to texture, a great part of the
solids consist of fibres more or less parallel. This may
be observed in the bones, especially of foetuses, in the
[Seite 14] muscles, tendons, ligaments, aponeuroses, and in cer-
tain membranes, as the dura mater, &c.

20. In other parts no fibres can be discovered, but
the texture is peculiar, has been called parenchyma
from the time of Erasistratus, and differs in different
viscera, especially the secreting, – of one kind in the
liver, of another in the kidneys.

21. But in all the structures, whether fibrous or paren-
chymatous, there is interwoven a general mucous web,*
commonly styled cellular, but improperly, because it
rather is continuous, equal, tenacious, ductile, sub-
pellucid, and glutinous. By handling, it is easily
converted into a cellular and vesicular membrane, and
demands a place among the most important and re-
markable constituents of the body. (A)

22. For, in the first place, many solid parts, v.c.
most membranes and cartilages, may by long continued
maceration be resolved into it alone. With some it is
so intimately united, as to afford a receptacle and sup-
port for other constituents: v.c. the hardest bones
consisted at first of cartilage, that was originally con-
densed mucous membrane, but has since become dis-
tended by the effusion of bony matter into its substance,
which is rendered more lax and cellular. In fact, it is
universally present in the solids, if we except the epi-
dermis, nails, hairs, and the vitreous exterior of the
corona of the teeth, in which I have never been able to
discover it by employing the strongest acid.

23. To the muscles and membranes especially it
[Seite 15] serves for separation from other parts; to the vessels
and nerves for support; and to every part it acts as
the common medium of connection.

24. From these facts, two inferences may be drawn.
First: That this membrane is so fundamental a consti-
tuent of our structure, that, were every other part re-
moved, the body would still retain its form.

Secondly: That it forms a connection between all
parts of the system, however different from each other
in nature or remote in situation: – a circumstance
worthy of attention, as putting an end to the verbal
disputes respecting the continuation of membranes, and
affording an explanation of many morbid phenomena.

25. As most of the solids owe their existence to this
membrane, so again its origin is derived from the lymph
of the blood. I have found the lymph changed into
this membrane, when transuded on the surface of in-
flamed lungs, and, by forming false membranes, it
afterwards unites these organs to the pleura.

26. We shall now consider some varieties of this
membrane. In general, it is more delicate, caeteris pa-
ribus, in man than in animals, – a distinguishing prero-
gative, by which our sense is rendered more delicate,
and our motions and other functions more perfect.*
Among different individuals, it varies much in laxity
and firmness, according to age, sex, temperament, mode
of life, climate, &c.

Finally, it varies in different parts; – more lax in the
palpebrae and preputium, and behind the fraenum of the
tongue; less so around the ears.

[Seite 16]

27. Besides the purposes before mentioned (22,) (23),
it is destined for the reception of several kinds of fluids.
Its chief use in this respect is to receive that serous
halitus which moistens and lubricates every part. This,
when formed by the blood vessels, it imbibes like a
sponge and delivers over to the lymphatics, thus consti-
tuting the grand connection between these two systems
of vessels.

28. In certain parts its office is to contain peculiar
fluids; v.c. in the eye, existing as the vitreous mem-
brane, it contains the vitreous humour: in the bones,
as the medullary membrane (improperly denominated
internal periosteum), the marrow; in soft parts, it is in
great abundance, and contains the rest of the fat, of
which we shall speak hereafter.


NOTE.

(A) Since this structure neither secretes mucus, nor consists
of mucus, but chiefly of what becomes gelatine by the operation
of boiling water, the generally received appellation of cellular
membrane
appears preferable to that of mucous tela adopted by
Blumenbach from Bordeu,* and especially in this work, as our
author (40) suggests the title of vis cellulosa for the contractile
power of the membrane.

SECT. IV.
OF THE VITAL POWERS IN GENERAL, AND PARTICU-
LARLY OF CONTRACTILITY.

[Seite 17]

29. Hitherto we have spoken of the solids as
the constituents of the system; we now shall view them
as endowed with vitality, – capable of receiving the
agency of stimuli, and of performing motions.

30. Although vitality* is one of those subjects which
are more easily known than defined, and usually indeed
rendered obscure rather than illustrated by an attempt
at definition, its effects are sufficiently manifest and
ascribable to peculiar powers only. The epithet vital
is given to these powers, because on them so much
depend the actions of the whole body during life and
of those parts which for a short time after death pre-
serve their vitality, that they are not referrible to any
qualities merely physical, chemical, or mechanical.

31. The latter qualities, however, are of great im-
portance in our economy. By physical powers, de-
pendent on the density and figure of the humours of the
eye, the rays of light are refracted to the axis; by me-
chanical, the epiglottis is elastic; by chemical affinity,
the changes of respiration are effected. But the perfect
difference of these dead powers from those which we
[Seite 18] are now about to examine, is evident on the slightest
comparison of an organised economy with any inorganic
body, in which these inanimate powers are equally
strong.

32. Indeed the vital powers are most conspicuously
manifested by their resistance and superiority to the
others; v.c. during life, they so strongly oppose the
chemical affinities which induce putrefaction, that Stahl
and his followers referred their notion of life to this an-
tiseptic property;* they so far exceed the force of
gravity, that, according to the celebrated problem of
Borelli, a dead muscle would be broken asunder by
the very same weight, which, if alive, it could easily
raise; &c.

33. As on the one hand, the vital properties are com-
pletely different from the properties of dead matter, so,
on the other, they must be carefully distinguished from
the mental faculties which will form the subject of the
next chapter: between them, however, there exists an
intimate and various relation, observable in many phe-
nomena, but especially in the diversity of tempera-
ment.

34. The vital energy is the very basis of physiology,
and has therefore been always noticed, though under
different appellations. The titles of impetum faciens,
innate heat, archaeus, vital spirit, brute life, head of
the nervous system, active thinking principle, vital
tonic attraction, have been bestowed upon it by dif-
ferent authors.

[Seite 19]

35. Nor has there been less variety in the notions and
definitions to which it has given rise; though in this
one point all have agreed, – that its nature and causes
are most obscure.

36. As to the question so long agitated by physiolo-
gists, – whether the diversity of the phenomena exhibited
in the similar parts of the living solid is to be attri-
buted to modifications only, or to distinct species, of
the vital energy, we think it best to establish distinct
orders of the vital powers,
according to the variety of
phenomena by which they are manifested.

37. These phenomena are threefold. – Organic for-
mation
and increase; motion in the parts when formed;
sensation from the motion of certain similar parts.

38. The first requisite involved in the name and notion
of an organised body, is a determinate form designed
for certain ends. That species, therefore, of the vital
powers is most general, which produces the genital and
nutritive fluids and prepares them for organic nature.
This species we have denominated the nisus formativus,
since it is the source of all generation, nutrition, and
reproduction, in each organised kingdom.

39. Those vital powers which are manifested by
motion, (37) properly so called, in parts already formed,
may be divided into common and proper. The common
are those belonging to similar parts which are widely
distributed: v.c. contractility to the mucous structure;
irritability to the muscular fibre. The proper are those
possessed only by individual organs whose motions
are peculiar and characteristic.

40. Contractility is as generally distributed as the
mucous structure, which it may be said to animate; and
therefore would perhaps not improperly be called the
[Seite 20] vis cellulosa. It is characterised by a simple and not
very sensible effort of the mucous web to contract and
react upon its contents, especially upon its source of
moisture – the serous vapour, and to propel this into
the lymphatic system.*

41. Irritability, we mean the irritability of Haller, is
peculiar to the muscles, and may be called the vis mus-
cularis.
It is marked by an oscillatory or tremulous
motion, distinguished from the action of simple con-
tractility, by being far more permanent, and by occur-
ring far more easily on the application of any pretty
strong stimulus.

42. Such are the common (39) moving vital powers.
But some organs differ from the rest so much in their
structure, motions, and functions, as not to come under
the laws of the common orders of vital powers. We
must, consequently, either reform the characters of these
orders, institute new ones, and extend their limits, or,
till this be done, separate these peculiar motions from
the common orders, and designate them by the name of
vitae propriae. As examples may be adduced, the
motions of the iris; the erection of the nipple; the
motions of the fimbriae of the Fallopian tubes; the
action of the placenta and of the womb during labour;
[Seite 21] and probably the greater part of the function of se-
cretion.*

43. So much in regard to the vital powers displayed
by motion (37, 39, 42). We have now to speak of
sensibility, which is peculiar to the nervous medulla
communicating with the sensorium. It bears the title
of vis nervea, and is the cause of perception when irri-
tation is excited in parts to which it is distributed.

44. The order which we have followed in enume-
rating the vital powers, (38, 43) is that in which they
successively arise both during our formation and after
birth.

The nisus formativus must take place before we can
ascertain the existence of the new conception.

Then contractility is exerted in the gelatinous sub-
stance of the embryo.

When the muscular fibres are produced, they acquire
irritability.

In those few organs whose motions cannot properly
be referred either to contractility or irritability, there
next exists a vita propria.

Finally, after birth, sensibility is superadded.

45. Similar also is the order, according to which the
vital powers, both common and proper, are distributed
to the organised bodies of each kingdom.

[Seite 22]

The formative power must be most universal;
without it indeed organisation cannot be conceived to
exist.

Contractility likewise is common to each kingdom.

Irritability and sensibility, in the sense above ex-
plained, are peculiar to animals.

Lastly, the vita propria is variously observable in
some organs, particularly the generative, both of certain
animals and vegetables.

46. It is scarcely necessary to remark, that most of
these modes of vital energy, though necessarily distin-
guished into orders, are intimately connected; v.c. the
mucous web, forming the basis and seat of contractility
in so many organs, is interwoven also with the irritable
muscular fibres* and the sensible nerves.

47. Whatever may have been the opinions of physi-
ologists respecting the difference or identity of the vital
powers, it is universally agreed that they exist in the
similar solid parts, as the ancients called them, of which
the organs or dissimilar parts are composed. But it
has been disputed, and particularly of late, whether
vitality is peculiar to the solids or common also to the
fluids; and, the latter being granted, whether or no the
blood alone is so endowed.

48. As to the first question, the whole natural history
of each organic kingdom, as far as it has hitherto been
cultivated, abundantly shows that those living parts,
however delicate, of all known animals and vegetables,
are solid; – a circumstance necessarily implied in their
determinate figure destined for certain uses. For, not
[Seite 23] to speak of entire animals (which, however simple, as
worms, are nevertheless supplied with enveloping mem-
branes) the newly laid egg, though at first sight merely
fluid, on a more careful examination is discovered to
consist of different membranes, of the halones, the cica-
tricula, &c.

Humidity is indeed necessary in the living solid for
the exertion of vitality. But that vitality exists in the
solid, as solid, is proved by the well-known instances
of animalcules and the seeds of plants, in which,
although long dried, the vital principle is so entire, that
they again live and germinate.

49. With respect to the supposed exclusive vitality
of the blood, I candidly confess that no fact has been
adduced in its favour since the time of Harvey, which
might not, I think, be more easily, simply, and naturally
explained on the contrary supposition.

For example, the incorruptibility of the blood during
life, is far more explicable by the perpetual changes
which it undergoes, especially in respiration.

That the blood is the material from which the living
solids are produced, is no stronger an argument of its
vitality, than the formation of nymphaeae and of so
many other remarkable plants would be for the vitality
of water.

It is difficult to comprehend how the coagulation of
the lymph of the blood can demonstrate its vitality.
The organic formation of this lymph in generation, nu-
trition, and reproduction, depends not upon the lymph
itself, as lymph, but upon the action of the nisus for-
mativus (38) upon it.

50. Those who formerly contended* that the blood
[Seite 24] acquires in the lungs from the air a certain principle to
be universally distributed during circulation, for the
purpose of imparting motion, &c. to the organs, were
right, if they regarded that principle (analogous to the
oxygen of the moderns) as the stimulant of the living
solid; wrong, if they regarded it as vitality itself.

51. For it is on all hands agreed, that no motion oc-
curs but upon the action of stimuli, to receive which
action the vital powers are naturally adapted and
intended.

52. These stimuli,* however multifarious, are conve-
niently reduced to three classes; – chemical, mechanical,
and mental. For the present, we shall say nothing of
their various modes of action, – in some instances
direct, – in others indirect, by sympathy and sensorial
reaction. It is sufficient at present to cite a few ex-
amples of functions, to which each class of stimuli
conspires: such is the increased secretion of tears,
saliva, bile, &c. and the venereal turgescence of the
genitals.

53. If the nature of stimuli is infinitely various, no
less so are their effects, according to their nature, inten-
sity, or continued and repeated application to the living
solid. Hence they are generally divided into exciting
and depressing.

54. The power of certain stimuli in increasing the
[Seite 25] effects of others, is very remarkable: v.c. the power of
caloric, upon which probably national temperament
chiefly depends.* That of joy, a most energetic mental
stimulus, is similar. Likewise perhaps that of
oxygen, (50) by whose chemical stimulus the vital
powers, particularly irritability, are greatly excited,
and more disposed to react, upon the impulse of other
stimuli.

55. Not less considerable than the variety of stimuli,
is that more minute discrepancy of the different organs,
and of the same organs in different individuals, accord-
ing to age, sex, temperament, idiosyncrasy, habit, mode
of life, &c., to which are owing the diversified effects of
the same stimuli upon different organs, and even upon
the same in different individuals, and upon which
depends what the English have lately termed specific
irritability.
§

56. Lastly, the influence of stimuli by means of sym-
pathy,
is very extraordinary: by its means, if one part
is excited, another, frequently very remote, consents in
feeling, motion, or some peculiar function.ǁ

[Seite 26]

The primary and most extensive cause of sympathy
must be referred to the nerves,* and indeed chiefly to
the sensorial reaction; so that if one nervous portion
is excited, the sensorium is affected, which, reacting by
means of the nerves on another part, draws it into con-
sent with the first, although there exist between them no
immediate nervous connection. Such is the sympathy
of the iris, when the retina is stimulated by light; and
of the diaphragm during sneezing, when the Schnei-
derian membrane is irritated.

There are other examples of sympathy, in which the
nerves, if they have any, have a more remote and ac-
cessory, share: among these must be placed the sym-
pathy along the blood vessels, strikingly instanced
between the internal mammary and epigastric arteries,
especially in advanced pregnancy; that along the lym-
phatic vessels,
§ also most remarkable during pregnancy
and suckling; and again, that dependent on analogy of
structure and function,
v.c. the sympathy of the lungs
with the surface and intestines. (A)

[Seite 27]

57. The vital powers will be hereafter separately con-
sidered, under the distinct heads of our subject: – The
nisus formativus under the head of Generation; irrita-
bility under that of the Muscles; sensibility under that
of the Nervous System; the vita propria whenever
occasion requires.

58. Besides our former brief remarks (40) upon con-
tractility,
a few more minute will at present be very
appropriate.

It prevails universally,(40) wherever the mucous tela
is discoverable.

It is consequently most abundant in parts destitute of
proper parenchyma, but composed almost entirely of
mucous tela, v.c. in certain membranes: for no one will
deny their contractility, who reflects upon the spastic
motions of the dartos, the male urethra, or the gall
bladder, which during death is always closely contracted
upon any calculi it may contain.

It appears also in those viscera which consist chiefly
of this tela, v.c. in the lungs, whose external surface
we have found on living dissection very contractile; but
by no means, as Varnier asserted, truly irritable. (B)

The presence of contractility even in the bones, is
demonstrated by the shrinking of the alveoli after the
loss of the teeth, and by the process of necrosis, by
which the new bone, when the dead portion is extricated
from its cavity, contracts to its natural size and figure.

The vitreous substance of the teeth, being destitute of
this tela (22), possesses no contractility, as I think ap-
pears from the circumstance of its not shrinking, like
the alveoli, if a portion is separated by caries or
fracture.

59. This contractility of the mucous tela is the chief
[Seite 28] cause of strength, health, and beauty; since on it depend
the vital elasticity and fulness,* and indeed the tone of
parts, so elegantly decribed by Stahl; for by its means,
the mucous tela, to mention one only of its functions,
absorbs, during health, the serous fluid (27) like a
sponge, and propels it into the lymphatic vessels: in
disease, on the contrary, having lost its tone, it is filled
with water, giving rise to oedema and similar cachexies.

60. Finally, the great influence of this contractility
in producing the peculiar constitution and tempera-
ments of individuals, is manifest from its universal
existence, its close union with the other vital powers,
and from its infinite varieties and degrees in different
persons.


NOTES.

(A) John Hunter divides sympathy into general and partial;
such as fever from a wound, and convulsion of the diaphragm
from irritation in the nose. Partial sympathy he subdivides into
remote, contiguous, and continuous, – Where there is no evident
connection between the sympathising parts, sufficient to account
for the circumstance, – Where there is proximity of the sympa-
thising parts, – and Where, as most commonly, the sympathising
parts are continuous.

Bichat’s division is much better. It cannot be understood,
indeed, till after the perusal of the note to the sixth section.

[Seite 29]

He considers sympathy as affecting either animal sensibility or
contractility, or organic sensibility or contractility.

Sympathy does not arise from nervous communication, because
it frequently happens that no particular nervous communications
of sympathising parts are discoverable, while remarkable ones ex-
ist between other parts not disposed to sympathise.* Vegetables,
which have no nerves, shew sympathy: – if a leaflet of the sen-
sitive plant is stimulated by a burning glass, the whole leaf con-
tracts and the foot-stalk drops; when the branches of trees
feel the warmth of summer, the sap ascends in the roots; and
even in a frost it will ascend from the roots through the stem, if
a single branch is introduced into a hot-house.

Sympathy of animal contractility occurs only when the nerves
connecting the affected muscles with the brain, are entire; when
they were divided by Bichat, the convulsions in the correspond-
ing muscles ceased. The sympathies of the organic functions are
never ascribable, as many might imagine, to continuity of sur-
face; for after dividing the oesophagus of a dog, Bichat produced
vomiting equally as before, on irritating the fauces.

(B) Our author here, as below (135), means the pulmonary
portion of the pleura, and very properly regards this and other
serous membranes, as condensed cellular substance; that is, as
a substance not originally cellular and now condensed, but of
the same nature with the cellular membrane, though much more
compact.

SECT. V.
OF THE MENTAL FACULTIES.

[Seite 30]

61. Man, whom we have found possessed of a body,
answering completely both in matter and texture, as
well as vital powers, the purposes of its formation, is
endowed likewise with a mind, a ‘“divinae particula
aurae,”’ intimately connected with the body, and deve-
loping by education and exercise various kinds of facul-
ties, which we shall concisely enumerate, as far as they
belong to our subject.*

62. The sensibility of the nerves, mentioned above
among the vital powers, (43) constitutes, as it were, the
medium which propagates the impressions of stimuli
upon sensible parts, and especially upon the organs of
sense (to be hereafter examined), to the sensorial por-
tion of the brain, in such a manner that they are per-
ceived by the mind.

63. The mental faculty to be first enumerated, and
indeed to be placed at the bottom of the scale, is the
faculty of perception, by means of which the mind takes
cognizance of impressions made upon the body, and
chiefly upon the organs of sense, and becomes furnished
with ideas.

[Seite 31]

64. This faculty is assisted by another of an higher
order, – attention, which so directs the mind, when ex-
cited, to any idea, that it dwells upon that idea alone
and surveys it fully.

65. To preserve and recall the marks of ideas, is the
office of memory – that part of the mind, which, in the
language of Cicero, is the guardian of the rest.

66. Imagination,* on the contrary, is that faculty of
the mind, which represents not merely the signs, but the
very images, of objects in the most lively manner, as if
they were present before the eyes.

67. Abstraction forms general notions more remote
from sense.

68. Judgment compares and examines the relations of
the ideas of sense and of abstract notions.

69. Lastly reason – the most noble and excellent of
all the faculties, draws inferences from the comparisons
of the judgment.

70. The combination of these constitutes the intellectual
faculty;
but there is another order, relating to appetency,
the word being taken in its most extensive meaning.

[Seite 32]

71. For since we are impelled by various internal
stimuli to provide food and other necessaries, and
also to satisfy the sexual instinct, and are impelled the
more violently, in proportion as imagination inflames
our wishes, desires, properly so called, are thus pro-
duced; and if, on the other hand, the mind becomes
weary of unpleasant sensations, aversions occur.

72. Finally, that faculty which selects out of many
desires and aversions, and can at pleasure determine to
perform functions for certain purposes, is denominated
volition.

73. Our order of enumeration corresponds with that
of the development of the faculties, and with the
relation in which those termed brute – common to man
and animals, and those more or less peculiar to man,
stand to each other.


NOTE.

Dr. Gall gives a very different view of the mental faculties.
Instead of dividing them into memory, judgment, &c. as funda-
mental faculties; and viewing ‘“the Power of Taste, a genius for
Poetry, for Painting, for Music, for Mathematics,”’ &c. as ‘“more
complicated powers or capacities, which are gradually formed by
particular habits of study or of business;”’* he regards these last
powers as distinct faculties, and memory, judgment, &c. merely
as modes or varieties common to the action of each faculty. He
contends that when we see a boy, brought up exactly like his
brothers and sisters, displaying fine musical talents or an asto-
[Seite 33] nishing power of calculation, though in all other respects a
child, his pre-eminence cannot be explained by particular habits
of study or of business, nor by mere strength of judgment.

For my own part when I reflect upon the various talents and
dispositions of persons all in the same circumstances – how un-
successfully some apply, with the utmost perseverance, to a branch
of study, in which another under the same instructors, or perhaps
scarcely assisted at all, reaches excellence, with little trouble –
how early various tempers are developed among children of the
same nursery – how hereditary peculiarities of talent and charac-
ter are – how similar some persons are to each other in one re-
spect, and dissimilar in another – how positively contradictory
many points of the same character are found; I confess myself
unable to deny that there is one innate faculty for numbers, ano-
ther for colours, a third for music, &c. &c. with a variety of
distinct innate sentiments and propensities; and that memory,
judgment, &c. are but modes of action common to the different
faculties and partly to different sentiments and propensities.

The sentiments and propensities which Dr. Spurzheim enume-
rates, respect sexual love, love of offspring, inhabiting particular
situations, attachment, contention, destruction, construction, ac-
quirement, concealment, love of self, love of praise, cautious-
ness, benevolence, veneration, hope, conscientiousness, decision,*
and imitation. The particular intellectual faculties, according
to the same author, are for judging of form, size, weight,
colour, space, number, tune, order? time? He enumerates like-
wise a faculty relating to languages, one to the ludicrous, one to
poetry, one to judging of cause and effect, one to the cognisance
[Seite 34] of the ideas of all the other faculties, and one again to their
comparison.

I should be extremely sorry to affirm that this is a complete
or accurate account of the faculties, sentiments, and propensi-
ties of the human mind, or that Dr. Spurzheim’s book* con-
tains no bad reasoning nor ridiculous illustration; but I am
convinced that Dr. Gall has given us the first correct sketch of
the constituents of the human mind, whatever more labour may
be necessary to complete the detail, and has put us in the only
right road for learning all that can be known of it. (218. E)

Every sentiment and propensity was given us for a good pur-
pose, and it is only when one is naturally or by indulgence ex-
cessive, thwarting and Crossing the operation of others, and
especially of conscientiousness, that error occurs; and on
this subject the profound metaphysical sermons, preached at
the Rolls Chapel by the pious and exemplary Bishop Butler,
highly deserve perusal. The natural tendency of our faculties,
the Bishop proves, is to virtue. Their mutual thwartings oc-
casion the deformities of the moral world, exactly as the crossing
of physical laws gives rise to the blemishes of inanimate nature.
Nor do I believe that the beauties of the inanimate world surpass
the beauties of the moral, or that the deformities of the moral
are more appalling than the deformities of the physical. Both
are governed by wise general laws; good is the object, evil the
occasional, incidental, accompaniment. (666. F)

SECT. VI.
OF HEALTH AND HUMAN NATURE.

[Seite 35]

74. Since health,* which is the object of physiology,
depends upon such an harmony and equilibrium of the
matter and powers of the system, as is requisite for the
due performance of its functions, it is very evident how
the four principles, examined above, contribute to its
support.

75. Fluids properly prepared are the first requisite;
in the next place, solids duly formed from the fluids;
then the invigorating influence of the vital powers; lastly,
a sound mind in this sound body.

76. These four principles act and react perpetually
upon each other: the fluids are stimuli to the solids;
these again are calculated by their vital powers to ex-
perience the influence of these stimuli, and react upon
them. In reference to the intimate union of the mind
with the body, suffice it at present to remark, that it is
far more extensive than might at first be imagined. For
instance, the influence of the will is not confined within
the narrow limits of those actions designated voluntary
in the schools of physiology; and the mind, on the
other hand, is influenced by the affections of the body, in
many other ways than by the perceptions of sense.

[Seite 36]

77. From the endless variety and modification of the
conditions belonging to these four principles, it may be
easily understood what great latitude* must be given
to the notion of health. For since, as Celsus long ago
observed, every one has some part weaker than the rest,
Galen may in this sense assert with truth, that no one
enjoys perfect health. And even among those whom
we commonly regard as in good health, this is variously
modified in each individual.

78. Upon this endless modification is founded the
difference of temperaments; or, in other words, of the
mode and aptitude of the living solid§ in each indi-
vidual, to be affected by stimuli, especially the mental;
and again, of the mental stimuli, to be excited with
greater or less facility.

79. So various are the differences of degree and com-
bination in the temperaments, that their divisions and
orders may be multiplied almost without end. We
[Seite 37] shall content ourselves with the four orders commonly
received.* The sanguineous – excited most readily, but
slightly: The choleric – excited readily and violently:
The melancholic – excited slowly, but more permanently:
And the phlegmatic – excited with difficulty.

This division, although built by Galen upon an absurd
foundation borrowed from an imaginary depravation of
the elements of the blood, appears, if made to stand
alone, both natural and intelligible.

80. The predisposing and occasional causes of the
diversity of temperaments are very numerous; v.c.
hereditary tendency, habit of body, climate, diet, re-
ligion, mode of life, and luxury.

81. Besides the variety of temperaments, circum-
stances peculiar to every individual, by influencing the
number, as well as the energy and vigour, of the functions,
increase the latitude (77) in which the term health must
be received. In regard to age, the health of a new-born
infant is different from that of an adult; in regard to
sex, it differs in a marriageable virgin and an old woman
past child-bearing, and during menstruation and suck-
ling; in regard to mode of life, it is different in the
barbarous tribes of North America and in effeminate
Sybarites.

Moreover, in every person, custom has an extra-
ordinary influence over certain functions, v.c. sleep,
[Seite 38] diet; and has therefore acquired the name of second
nature.

82. The more functions flourish simultaneously in the
body, the more considerable is its life; and vice versâ.
Hence life is greatest when the functions have attained
their highest perfection in adult age; and least when
the functions, although very perfect, are fewer and more
sluggish, v.c. in the newly conceived embryo; life is
for the same reason less vigorous during sleep than
during the opposite state.

83. The functions have been long divided by physi-
ologists into four classes. This division, although not
unexceptionable nor exactly conformable to nature,*
may assist the memory.

1. The first class comprehends the vital functions, so
termed, because their uninterrupted and complete per-
formance is necessary to life. Such are the circulation
and respiration.

2. The second comprehends the animal functions, by
which animals are chiefly distinguished from vegetables.
Such is the connection of the mind with the body, espe-
cially sense and muscular motion.

3. The third is the natural, by means of which the
body is nourished.

4. The fourth, the genital, intended for the propaga-
tion of the species.

[Seite 39]

We shall now examine each of these separately, be-
ginning with the vital.


NOTE.

The consideration of a division as ancient as Aristotle, and
preferable to that which Blumenbach adopts, will perhaps form
an useful note to the eighty-third paragraph and the greater part
of the fourth section.

In this, the functions are arranged in two classes: – the ani-
mal constituting one peculiar to animals; and the vital and na-
tural united into another, common to vegetables and animals,
under the title of organic or vital. The generative, relating in
their object to the species rather than to the individual, and of
but temporary duration, are thrown into a separate and inferior
division, but in fact are merely part of the organic.

We owe the revival of this classification, and our knowledge
of the characteristics of each class of functions, to Dr. Wilson
Philip* and Xavier Bichat, although the latter, from having
published a work expressly on the subject, has received the whole
honour, both in great Britain and on the Continent.

The animal functions prove us feeling, thinking, and willing
beings: they are the actions of the senses which receive impres-
sions, of the brain which perceives them, reflects upon them,
and wills; of the voluntary muscles which execute the will in
regard to motion; and of the nerves which are the agents of
transmission. The brain is their Central organ. The vital or
[Seite 40] organic functions are independent of mind, and give us simply
the notion of life: they are digestion, circulation, respiration,
exhalation, absorption, secretion, nutrition, calorification. The
heart is their Central organ.

The organs of the animal functions are double and corres-
pondent, there being on each side of the median line of the
body, either two distinct organs, as the eyes, ears, extremities;
or two correspondent halves, as is the case with the brain, spi-
nal marrow, nose, tongue, &c.

The organs of the vital or organic functions, are in very few
instances double or situated with their centres in the median
line and possessed of symmetrical halves; witness the heart,
stomach, liver. There are indeed two kidneys, but they con-
tinually differ in size, figure, and situation: the two lungs are
very dissimilar.

Hence Bichat infers, that in the animal functions a harmony
of action in each organ or each half of the organ, is indispen-
sable to perfection, when both organs or sides act together;
and that if such harmony do not occur, it would be better for
one organ or one half to act alone. This is unquestionably true
of the eye, but can be supposed by analogy only with regard to
the brain, ears, &c. It certainly does not hold good in the
actions of the voluntary muscles, nor in the operations of the
brain or spinal marrow in willing those actions. From the du-
plicity of the organs it also happens that one side may cease to
act without detriment to the function of the other; while in the
vital or organic class no harmony of action is possible and the
derangement of any one part of an organ generally affects the
whole of it, – an obstruction in the colon disturbs the functions
of all the alimentary canal.

The animal functions experience periodical intermissions –
sleep. The organic or vital continue incessantly, suffering merely
remissions: – the blood constantly circulates, the perspiratory
fluid is constantly secreted, the stomach has no sooner digested
one meal than we commit another to it; yet we shall hereafter
[Seite 41] see that the actions of the heart, lungs, &c. have daily intervals
of remission.

The animal functions are much influenced by habit; the vital
or organic are considered by Bichat as removed from its influence.
The power of habit over our sensations and voluntary motions
is manifest: yet I think it equally great over the organic func-
tions. The operation of food and of all descriptions of ingesta
is most remarkably modified by habit; through it poisons be-
come comparatively innoxious, and divers bear a long suspension
of respiration.

Bichat regards the passions as directly influencing the organic
functions only, and springing from the state of the organs of
that class. Here he is to me perfectly unintelligible. Vexation
indeed disturbs the stomach, and fear augments the quantity of
urine; but does not vexation equally and as directly disturb the
mind – confuse the understanding, and occasion heat and pain
of the forehead? Are not, in fact, the passions a part of the
mind? – a part of the animal functions? They powerfully affect,
it is true, the organic or vital functions, but this shows the close
connection merely between the two classes of functions.

This connection is conspicuous in respiration, the mechanical
part of which belongs to the animal functions, the other to the
organic; and in the alimentary actions, in which the food is
swallowed and the faeces rejected by volition, and digestion,
&c. performed, independently of our influence, by the powers of
simple life. So close indeed is this connection, that every organ
of the animal class is the seat of organic functions; – in the vo-
luntary muscles, the organs of sense, and even in the brain, cir-
culation, secretion, and absorption are constantly carried on.
This connection is likewise apparent in the property of sensibility.
In the language of Bichat there are animal sensibility and contrac-
tility,
and organic sensibility and contractility, besides the common
extensibility of matter, which he terms extensibilité de tissu, and
common contractility upon the removal of distention, – Con-
tractilité par défaut d’extension,
confounded by Blumenbach
[Seite 42] (58. clause 5 and 6) with purely vital contractility, and indeed
greater during life than afterwards.* Animal sensibility is accom-
[Seite 43] panied by a perception in the mind, as in seeing, hearing, tasting,
smelling, feeling: animal contractility is excited by the volition
of the mind conveyed to the voluntary muscles by means of the
nerves. Organic sensibility is attended by no perception, and is fol-
lowed by contraction totally independent of the will: – the heart
feels, if we may so speak, (physiology has no proper term for
the idea) the stimulus of the blood, and, without our influence,
forthwith contracts; the lacteals feel the stimulus of the chyle
without our knowledge, and propel it without our assistance.
But although we never acquire the least direct voluntary power
over the actions of organic contractility, – over the peristaltic
motion of the intestines or the contractions of the blood vessels,
[Seite 44] yet every organ of the organic functions may have its organic
sensibility heightened into animal sensibility, as inflammation,
for instance of the pleura and the joints, daily demonstrates:
indeed, in some organs of that class of functions, we invariably
have sensation; – the stomach is the seat of hunger, in the lungs
we experience an uneasy sensation nearly as soon as their air is
expelled.

The nerves of the animal functions run to the brain or spinal
marrow; those of the organic chiefly to ganglia; but, as might
be expected, the two nervous systems have abundant com-
munications.

The animal functions have not only a shorter existence than
the organic from their necessity of alternate repose, but they
flourish for a shorter duration, – they do not commence till birth,
they decline, and, in the natural course of events, terminate,
earlier, – the organs of sense and the mental faculties fail before
the action of the heart and capillaries. The decay of the animal
functions must, in truth, be the consequence of the decay of the
organic, because there are fundamentally in every part organic
functions, – circulation, nutrition, &c. and the perfect perform-
ance of these in the organs of the animal functions is indispen-
sable to the perfect performance of the animal functions. Hence
the impairment of these organic functions, even to a small ex-
tent, must derange or diminish the animal functions, which will
thus decline while there is still sufficient life for the organic
functions to continue.

We thus find in every living system a class of functions, not
in themselves dependent upon mind, as perfect in the vegetable
as in the animal, and pervading every part of the system. In
animals there further exist certain parts which when endowed
with the common life of other parts, – with the organic proper-
ties, are able to perform peculiar functions which give us the
notion of mind: the organ of these functions is termed brain,
and, by means of nerves and medullary prolongations, it main-
tains a correspondence with the whole machine, influenced by
[Seite 45] and influencing the most distant parts. The phenomena of the
mind have been metaphysically considered in the fifth section;
they will be examined as functions of the nervous system in the
twelfth.

The organic functions depend on life in the proper accepta-
tion of the word. The word life should be regarded, like the
word attraction or repulsion, as merely an expression of a fact.
In this point of view it may be as easily defined as any other
expression. By life we generally mean the power of organised
matter to preserve its particles in such chemical relations as to
prevent other chemical relations from inducing disorganisation,
or even to increase or decrease by internal appropriation and
separation; to preserve in some measure a temperature distinct
from that of the surrounding medium; to move certain parts of
itself sensibly (as muscles) or insensibly (as the capillaries) inde-
pendently of mere impulse, attraction, or repulsion: or if not
organised (as the fluids which form the embryo, the blood,)
the power of matter produced by an organised body endowed
with the properties above mentioned, to resist the ordinary che-
mical influences, and directly form (as the genital fluids) an
organised system so endowed, or directly contribute (as the
blood) to the organised substance of an already formed system
so endowed.

That fluids are as susceptible of life as solids I cannot doubt.
There is no reason why they should not be so, although a person
who has not thought upon the subject may be as unable to con-
ceive the circumstance as a West Indian to conceive that water
may by cold become solid. It is impossible to deny that the male
and female genital fluids are alive, because from their union a liv-
ing being is produced that partakes of the vital qualities of each
parent. Accordingly Blumenbach, in his Commentatio de vitali
sanguinis,
* grants both male and female genital fluids to be alive,
[Seite 46] nothwithstanding that he fancies his victory over the defenders of
the blood’s life so complete, that like that of the unfortunate
Carthaginian Dido, as he says, ‘“in ventos vita recessit.”’ It is as
easy to conceive the blood to be alive as the genital fluids. The
great asserter of the life of the blood is Mr. Hunter,* and the
mere adoption of this view of the facts relative to that fluid by
Mr. Hunter, would entitle it to the utmost respect from me who
find the most ardent and independent love of truth, and the
genuine stamp of genius, in every passage of his works. The
freedom of the blood from putrefaction while circulating, and
its inability to coagulate after death from arsenic, electricity, and
lightning, may, like its inability to coagulate when mixed with
bile, be simply chemical phenomena, independent of vitality.
But its inability to coagulate after death from violent exercise,
anger, or a blow on the stomach, which deprive the muscles
likewise of their usual stiffness; its accelerated coagulation by
means of heat; perhaps its diminished coagulation by the ad-
mixture of opium; its earlier putridity when drawn from old
than from young persons; its freezing, like eggs, frogs, snails, &c.
more readily when once previously frozen (which change may be
supposed to have exhausted its powers); its directly becoming
[Seite 47] the solid organised substance of our bodies, while the food
requires various intermediate changes before it is capable of
affording nutriment; the inosculation of the vessels formed in
extravasated blood and secreted lymph with those of surrounding
parts; and finally the production of the genital fluids from the
blood itself; do appear to me very strong arguments in favour of
the life of the blood.* I am inclined with Mr. Hunter to be-
lieve that the chyle is alive, and that vivification commences even
in the stomach, although I should be sorry to go the same
length with Albinus, who granted life even to the excrement.
For the excretions must be regarded as dead matter, useless and
foreign to the system; and they all run with the greatest rapi-
dity into decomposition. In operating for retention of urine,
the surgeon finds this fluid abominably foetid; the faeces become
so when not discharged in due time; and the neglect of washing
the surface is the source of filthiness and disease.

The essential nature of life is an impenetrable mystery, and
no more a subject for philosophical inquiry than the essential
nature of attraction or of matter. To attempt explaining the phe-
nomena of life by a vital fluid is only increasing the intricacy of
the subject by an unfounded hypothesis, and always reminds
me of Mr. Dugald Stewart’s remark, – that ‘“There is even some
reason for doubting, from the crude speculations on medical
and chemical subjects which are daily offered to the public, whe-
ther it (the proper mode of studying nature) be yet understood
so completely as is commonly imagined, and whether a fuller
illustration of the rules of philosophising, than Bacon or his fol-
lowers have given, might not be useful even to physical in-
quirers.”’ We see matter in a certain state possessed of a cer-
tain power which we term life, and the object of physiology is
merely to observe its effects, just as it is the object of chemistry
to observe the circumstances of the affinity of different bodies and
[Seite 48] of physics to observe other phenomena of matter, without vainly
speculating on the essence of affinity or the essence of matter, to
comprehend which our faculties are in their nature incompetent.
By attributing life, the power of attraction, &c. to subtle and
mobile fluids, we not only do not advance a single step, for we
have still to explain what these fluids are and how they obtain
their powers, just as we had before in regard to common matter,
but we make the additional mysteries of their being united with
ordinary matter, and so united that life appears a power possessed
by it. The editors of a medical review have in vain searched Mr.
Hunter’s works for such an hypothesis,* and Mr. Lawrence has
had no better success, so that I apprehend his meaning has been
misunderstood by those who constitute him its patron. Grant-
ing for a moment that life depends on a peculiar fine fluid, we
have still to account for mind, because life is not mind, – a cab-
bage is as much gifted with life as the wisest man.

We have reason to believe that life never originates, but was
granted at the creation, and is communicated to assimilated mat-
ter and propagated from parent to offspring (622. B.); it is the
property of organised systems, producing various effects by
various kinds of organisation, but not quite peculiar to organised
matter, because capable of being possessed by matter in a fluid
state.§ [Seite 49] The animal functions demonstrate mind. This is seated in
the brain, to which the spinal marrow, nerves, and voluntary
muscles are subservient. Mind is the functional power of the
living brain. As I cannot conceive life any more than the power
of attraction unless possessed by matter, so I cannot conceive
mind unless possessed by a brain endowed with life. (666. F).
I speak of terrestrial or animal mind; with angelic and divine
nature we have nothing to do, and of them we know, in the
same respects, nothing. To call the human mind positively a
ray of the divinity, (Divinae particula aurae,* Ex ipso Deo decerp-
tus, Ex universa mente delibatus)
appears to me absolute non-
sense. Brutes are as really endowed with mind, – with a con-
sciousness of personality, with feelings, desire, and will, as man.
Every child is conscious that it thinks with its head, and common
language designates this part as the seat of mind. Observation
shows that superiority of mind in the animal creation is exactly
commensurate with superiority of brain (666. F); that activity
of mind and of brain are coequal; and that as long as the brain
is endowed with life and remains uninjured, it, like all other
[Seite 50] organs, can perform its functions, and mind continues; but, as
in all other organs, when its life ceases, its power to perform its
function ceases, and the mind ceases; when causes of disturbance
affect it, the mind is affected; if originally constituted defec-
tive, the mind is defective; if fully developed and properly acted
on, the mind is vigorous; accordingly as it varies with age, is
the mind also varied, – the mind of the child is weak and ex-
citable, of the adult vigorous and firm, and of the old man
weak and dull, exactly like the body;* and the character of the
mind of an individual agrees with the character of his body,
being equally excitable, languid, or torpid, evidently because
the brain is of the same character as the rest of the body to
which it belongs, – the female mind exceeds the male in excita-
bility as much as her body; the qualities of the mind are also
hereditary, which they could not be, unless they were, like
[Seite 51] our other qualities, corporeal conditions; and the mind is often
disordered upon the disappearance of a bodily complaint, just as
other organs, besides the brain, are affected under similar cir-
cumstances, – the retrocession of an eruption may affect the
lungs, causing asthma, the bowels, causing enteritis, or the
brain, causing insanity; phthisis and insanity sometimes alter-
nate with each other, just like affections of other organs. The
argument of Bishop Butler, that the soul is immortal and in-
dependent of matter because in fatal diseases the mind often
remains vigorous to the last,* is perfectly groundless, for any
function will remain vigorous to the last if the organ which
performs it is not the seat of the disease, nor much connected
by sympathy or in other modes with the organ which is the seat
of the disease, – the stomach often calls regularly for food and
digests it vigorously, while the lungs are almost completely con-
sumed by ulceration. All the cases that are adduced to prove
the little dependence of the mind on the brain, are adduced in
opposition to the myriads of others that daily occur in the usual
course of nature, and are evidently regarded as extraordinary
cases by those who bring them forward. An exact parallel to
each may be found in affections of every other organ, and each
admits of so easy an explanation that it may be always truly said,
‘“Exceptio probat regulam.”’

[Seite 52]

In contending that the mind is a power of the living brain,
and the exercise of it the functions of that organ, I contend for
merely a physical fact, and no Christian who has just conceptions
of the Author of Nature will hesitate to look boldly at nature as
she is, lest he should discover facts opposite to the pronunciations
of revelation. For the word and the works of the Almighty can-
not contradict each other. Lord Bacon accordingly, in a very
memorable part of his writings, directs the physical enquirer to
be uninfluenced by religious opinions,* as the more indepen-
dently truth is pursued the sooner will it be gained, and the
sooner will the real meaning of the divine statement of natural
things, and its identity with physical fact, be established.

The assertion, however, that the mind is a power of the living
brain, is not an assertion that it is material, for a power or
property of matter cannot be matter.

Neither is it an assertion, that this power cannot be a some-
[Seite 53] thing immortal, subtle, immaterial, diffused through and con-
nected with the brain. A physical enquirer has to do with only
what he observes. He finds this power, but attempts not to
explain it, – he simply says the living brain has this power, and
leaves others at liberty to fancy an hypothesis of this power
being a subtle, immaterial, immortal substance, exactly as they
fancy life to be a subtle fluid, or perhaps, though very extra-
ordinarily, the same subtle fluid (if subtlety is immateriality and
immortality), elucidating the subject no more than in the case of
life, and equally increasing the number of its difficulties,* as
though we were not created beings, or not altogether ignorant
what matter is, or of what it is capable and incapable; as though
matter exhibited nothing but extension, attraction, and inertness;
and as though the Almighty could not, if it seemed good to him,
endow it with the superaddition of life, and even of feeling and
will.

[Seite 54]

Nor does this assertion imply that the resurrection from the
dead is impossible or even improbable. The physical enquirer,
finding the mind a power of the brain, and abstaining from
hypothesis, must conclude that, in the present order of things,
when the brain ceases to live the power necessarily ceases, – that,
in the language of scripture, Dust we are and unto dust we all
return, – that our being is utterly extinguished and we go back
to the insensibility of the earth whence we were taken.* Our
consciousness of personality can afford no reason for imagining
ourselves immortal and distinct from earth, more than brutes,
for this the fly possesses equally with the philosopher about
whose head it buzzes. The moral government of the world,
the sublime reach of our acuteness, the great improvableness of
our characters, –

‘“Our innate pleasing hope, our fond desire,’
‘Our longing after immortality,’
‘Our secret dread and inward horror of falling into nought,”’

completely harmonise with a life hereafter, but fall so short of
proof as to have left the wisest of antiquity, – Solomon, Socrates,
Cicero, &c. in uncertainty,§ when they saw how death reduced
us to our pristine elements. The hope of immortality which
such reflections, and possibly also the tradition of Enoch’s
translation, inspired,ǁ assisted by the desire of explaining every
thing in some way or other, first, I apprehend, made men
attempt to find, in the imagined ethereal essence of the soul, a
[Seite 55] reason for our not totally perishing as our senses would lead us
to suppose. But because we refuse to listen to a mere hypo-
thesis we are not to deny the resurrection. For if a divine
revelation pronounce that there shall be another order of things
in which the mind shall exist again, we ought firmly to believe
it, because neither our experience nor our reason can inform us
what will be hereafter, and we must be senseless to start
objections on a point beyond the penetration of our faculties.*
We have a Divine revelation which so pronounces, – not that we
are naturally immortal, but that ‘“in Adam (by nature) all die,”’ –
have our being utterly extinguished, and in another order of
things, – when the fashion of this world shall have passed away
and time shall be no more, that in Christ (by the free, additional,
gift of God, granted through the obedience of our Saviour) we
shall all again be made alive. A miracle would not have been
necessary to convince us of a truth discoverable by sense and
reason. That the promises of revelation are the proper and only
foundation of our hopes of immortality, was the opinion of the
late Regius Professor of Divinity in the University of Cambridge,
whose gigantic intellect and sincere love of truth render his
opinions weightier than the decrees of councils. – ‘“I have no
hope of a future existence,”’ says he, ‘“except that which is
[Seite 56] grounded on the truth of Christianity.”’* While those are to be
pitied who think there can be any thing like an argument against
a future life in another order of things, if declared by revelation,
I am deeply hurt that others should think it necessary to attempt
rendering the pronunciations of scripture more probable by an
hypothesis which is at best but the remains of unenlightened
times, and require any assurance besides that of the Gospel
[Seite 57] which ‘“has brought life and immortality to light.”’* They should
reflect that the belief of an immaterial substance removes no ima-
gined difficulty, as the resurrection will be positively of body, and
that therefore our minds will appear as much a property of body
hereafter as at present. The sound and excellent Paley, following
Locke who shews in his third letter to Bishop Stillingfleet that the
Scriptures do not say our identical bodies (σώματα) will be raised,
but merely οἱ νεκροὶ or πὰντες, with bodies, draws, in his sermon
on the state after death, the following conclusions from various
intimations in the New Testament: –

‘“First, that (at the resurrection) we shall have bodies.’

‘“2. That they will be so far different from our present bodies,
as to be suited, by that difference, to the state and life into which
they are to enter, agreeably to that rule which prevails throughout
universal nature, that the body of every being is suited to its
state, and that when it changes its state it changes its body.’

[Seite 58]

‘“3. That it is a question by which we need not be at all dis-
turbed whether the bodies with which we shall arise be new
bodies, or the same bodies under a new form; for,’

‘“4. No alteration will hinder us from remaining the same,
provided we are sensible and conscious that we are so, any more
than the changes which our visible person undergoes even in
this life, and which from infancy to manhood are undoubtedly
very great, hinder us from being the same, to ourselves and in
ourselves, and to all intents and purposes whatsoever.’

‘Lastly, That though from the imperfection of our faculties,
we neither are, nor without a constant miracle upon our minds,
could be made able to comprehend the nature of our future bodies,
yet we are assured that the change will be infinitely beneficial;
that our new bodies will be infinitely superior to those which we
carry about with us in our present state.”’*

The Archdeacon’s fourth conclusion removes an objection that
might suggest itself to some. St. Paul declares the resurrection
to be ‘“a mystery:”’ it will in truth be a miracle, and vain were
the enquiry ‘“how can these things be?”’ On these subjects
I wish to touch with modesty and reverence, and if I have written
a syllable that can be proved contrary to Scripture or to the Arti-
cles of the Church of England, I acknowledge it false and declare
it unsaid. The view of nature is really a revelation, and cannot
without impiety be thought contradicted by any inspired declara-
tion. I think with Bishop Watson that the farther general science
extends as years pass on, the better will the volumes of our faith
be understood. Next to the irreligious lives of many professed
[Seite 59] Christians, nothing has contributed more to the infidelity of
thoughtless men than the pretence that various opinions are
necessarily connected with the grand doctrines of salvation.
The elucidation of the first chapter of Genesis by geology, and
the erroneous views taken of it through ignorance of science
by a truly good man, were lately displayed in an able article of
the Quarterly Review.

SECT. VII.
ON THE MOTION OF THE BLOOD.

[Seite 60]

84. The blood, to whose great and multifarious im-
portance in the system we have slightly alluded, (16)
is conveyed, with a few exceptions, (5) into the most
internal and extreme recesses. This is proved by the
minute injection of the vessels, and by the well known
fact of blood issuing from almost every part on the
slightest scratch.

85. This purple fluid does not, like an Euripus, ebb
and flow in the same parts, as the ancients imagined,
but pursues a circular course; so that being propelled
from the heart into the arteries, it is distributed through-
out the body, and returns again to the heart through
the veins.*

86. We shall, therefore, say something at present
of the vessels which contain the blood; and afterwards,
of the powers by which they propel and receive it.

87. The vessels which receive the blood from the
heart and distribute it throughout the body, are termed
arteries. These are upon the whole less capacious than
[Seite 61] the veins; but in adult and advanced age especially,
of a texture far more solid and compact, very elastic
and strong.

88. The arteries consist of three coats:*

I. The exterior, called, by Haller, the tunica cellu-
losa propria;
by others, the nervous, cartilaginous, ten-
dinous, &c. It is composed of condensed cellular
membrane, externally more lax, internally more and
more compact: blood vessels are seen creeping upon
it: it gives tone and elasticity to the arteries.

II. The middle coat consists of transverse fibres,
lunated or falciform, and almost of a fleshy nature:
hence this has the name of muscular coat, and ap-
pears to be the chief seat of the vital powers of the
arteries.

III. The inner coat lining the cavity of the arteries
is highly polished and smooth. This is much more dis-
tinct in the trunks and larger branches than in the
smaller vessels.

89. Every artery originates either from the pulmo-
nary artery (the vena arteriosa of the ancients), which
proceeds from the anterior ventricle of the heart and
goes to the lungs; or from the aorta, which proceeds
from the posterior ventricle and is distributed through-
out the rest of the system. These trunks divide into
branches, and these again into twigs.

90. According to the commonly received opinion,
[Seite 62] the united capacity of the branches is greater than that
of the trunk from which they arise. But I fear that
this is too general an assertion, and even that the mea-
sure of the diameter has been sometimes improperly
confounded with that of the area. I myself have never
been able to verify it, although my experiments have
been frequently repeated, and made, not on vessels in-
jected with wax, but on the undisturbed vessels of
recent subjects, on the innominata and its two branches
– the right carotid and subclavian, on the brachial and
its two branches – the radial and ulnar.*

The inconstancy of the proportion between the capa-
city of the branches and trunks is clearly shewn by the
various size of the vessels under different circum-
stances, v.c. by the relative capacity of the inferior
thyroid artery in the infant and the adult; of the epi-
gastric artery and also of the uterine vessels in a virgin
and a woman far advanced in pregnancy; of the
omental vessels during the repletion and vacuity of the
stomach.

91. The arteries, after innumerable divisions and
important anastomoses connecting different branches,
terminate at length in the beginning of the veins. By
this means, the blood is conveyed back again to the
heart. The distinction between artery and vein at the
point of union, is lost.

[Seite 63]

In the present state of our knowledge, the umbilical
vessels are to be regarded as the only exception to the
termination of arteries in veins. We shall shew that
they are connected with the uterine vessels by the in-
tervention of a spongy substance, called parenchyma.

92. Another description of vessels arise universally
from the arteries and are called colourless, from not con-
taining pure blood, either on account of their minute-
ness, or of their specific irritability which causes them
to reject that fluid. These are the nutrient and other
secretory vessels: of which hereafter.

93. The blood conveyed from the heart by the arte-
ries is carried back by the veins.

These are very different in function and structure
from the arteries, excepting however the minutest of
both systems, which are indistinguishable.

94. The veins, excepting the pulmonary, are upon
the whole more capacious than the arteries; are more
ramified; much more irregular in their course and divi-
sion; in adult age, softer and more elastic, but still
very firm and remarkably expansile.

95. Their coats are so much thinner that the blood
appears through them. They are likewise less in num-
ber, being solely a cellular external, somewhat resem-
bling the nervous of the arteries; and a very polished
internal, also nearly agreeing with that of the arteries.

A muscular coat exists in the largest trunks only.

96. The interior coat forms, in most veins of more
than a line in diameter, very beautiful valves, of easy
play, resembling bags, generally single, frequently dou-
ble, and sometimes treble, so placed, that the fundus
lies towards the origin of the vein, the limbus towards
the heart.

[Seite 64]

These valves are not found in some parts; not in the
brain, heart, lungs, secundines, nor in the system of
the vena portae.

97. The twigs, or, more properly, the radicles, of the
veins, unite into branches, and these again into six
principal trunks: viz. into the two cavae, superior and
inferior; and the four trunks of the pulmonary vein (the
arteria venosa of the ancients).

The vena portae is peculiar in this, that, having en-
tered into the liver, it ramifies like an artery, and its
extreme twigs pass into the radicles of the inferior
cava, thus coalescing into a trunk.

98. That the blood may be properly distributed and
circulated through the arteries and veins, nature has
provided the heart,* in which the main trunks of all
the blood vessels unite, and which is the grand agent
and mover of the whole system, – supporting the chief
of the vital functions with a constant and truly wonder-
ful power, from the second or third week after concep-
tion to the last moment of existence.

99. The heart alternately receives and propels the
blood. Receiving it from the body by means of the
superior and inferior vena cava, and from its own sub-
stance through the common valvular orifice of the
coronary veins, it conveys that fluid into the anterior
sinus and auricle; and thence into the corresponding
ventricle, which, as well as the auricle, communicates
[Seite 65] with both orders of its own vessels by the openings of
Thebesius.*

100. From this anterior, or, in reference to the heart
of some animals, right, ventricle, the blood is impelled
through the pulmonary artery into the lungs: returning
from which, it enters the four pulmonary veins and pro-
ceeds into their common sinus and the left, or, as it is
now more properly termed, posterior auricle.

101. It flows next into the corresponding ventricle;
and then passing into the aorta, is distributed through
the general arterial system and the coronary vessels of
the heart.

102. Having proceeded from the extreme twigs of
the general arterial system into the radicles of the
veins, and from the coronary arteries into the coronary
veins, it finally is poured into the two venae cavae, and
then again pursues the same circular course.

103. The regularity of this circular and successive
motion through the cavities of the heart is secured,
and any retrograde motion prevented, by the valves
which are placed at the principal openings, viz. at the
openings of the auricles into the ventricles, and of the
ventricles into the pulmonary artery and aorta.

104. Thus the ring, or venous tendon, which forms the
limit of the anterior auricle and ventricle, descending
into the latter cavity, becomes these tendinous valves.§
These were formerly said to have three apices, and
[Seite 66] were therefore called triglochine or tricuspidal: they
adhere to the fleshy pillars, or, in common language,
the papillary muscles.

105. In a similar manner, the limits of the posterior
auricle and ventricle are defined by a ring of the same
kind, constituting two valves, which, from their form,
have obtained the appellation of mitral.*

106. At the opening of the pulmonary artery and
aorta are found the triple semilunar or sigmoid valves,§
fleshy and elegant, but of less circumference than the
mitral.

107. It is obvious how these valves must prevent
the retrocession of the blood into the cavae. They
readily permit the blood to pass on, but are expanded,
like a sail, against it, by any attempt at retrograde
movement.

108. The texture of the heart is peculiar: fleshy, in-
deed, but very dense and compact, far different from
common muscularity.ǁ It is composed of fasciculi of
fibres, more or less oblique, here and there singularly
branching out, curiously contorted and vorticose in
their direction, lying upon each other in strata, closely
interwoven between the cavities, and bound by four
cartilaginous bands to the basis of the ventricles, which
are thus supported and distinguished in their texture
from the fibres of the auricles.**

[Seite 67]

109. These fleshy fibres are supplied with very soft
nerves* and an immense number of blood vessels,
which arise from the coronary arteries, and are so in-
finitely ramified, that Ruysch described the whole
structure of the heart as composed of them.

110. The heart is loosely contained in the pericar-
dium.
§ This is a membraneous sac, arising from the
mediastinum, very firm, of the same figure as the heart,
and moistened by an exhalation from the arteries of that
organ. Its importance is evinced by its existence being,
in red blooded animals, as general as that of the heart;
and by our having only two instances on record of its
absence in the human subject.ǁ

111. By this structure, the heart is adapted for per-
petual and equable motions, which are an alternate
systole and disastole, or contraction and relaxation of
the auricles and ventricles in succession.

112. Thus, as often as the auricles contract to impel
the blood of the venae cavae and pulmonary veins into
the ventricles, these are at the same moment relaxed,
to receive the blood: immediately afterwards, when
the distended ventricles are contracting to impel the
blood into the two great arteries, the auricles relax
and receive the fresh venous supply.

[Seite 68]

113. The systole of the ventricles, upon which is
said to be spent one third of the time of the whole ac-
tion of the heart, is performed in such a way, that their
external portion is drawn towards their septum, and
the apex of the heart towards the base.* This at first
sight seems disproved by the circumstance of the apex
striking against the left nipple and consequently ap-
pearing elongated, – a circumstance, however, to be
attributed to the double impetus of the blood flowing
into the auricles and expelled from the ventricles, by
which the heart must be driven against that part of the
ribs. (A)

114. The impulse imparted by the heart to the blood,
is communicated to the arteries, so that every systole
of the heart is very clearly manifested in those arteries
which can be explored by the fingers and exceed 1/6 of
an inch in diameter, and in those also whose pulsation
can be otherwise discovered, as in the eye and ear.
The effect upon the arteries is called their disastole,
and is correspondent and synchronous with the systole
of the heart.

115. The quickness of the heart’s pulsations during
health varies indefinitely; chiefly from age, but also
from other conditions which at all ages form the pecu-
liar health of an individual; so that we can lay down
no rule on this point. I may, however, be permitted
to mention the varieties which I have found in our
climate at different ages, beginning with the new-born
[Seite 69] infant, in which, while placidly sleeping, it is about
140 in a minute.

Towards the end of the first year, about 124
. . . . . . . . . . . . . . . . . . . second 110
. . . . . . . . . . . . . . . . . . . third and fourth 96
When the first teeth begin to drop out 86
At puberty 80
At manhood 75
About sixty 60

In those more advanced, I have scarcely twice found
it alike.

116. The pulse is, caeteris paribus, more frequent
in women than men, and in short than tall persons.
A more constant fact, however, is its greater slowness
in cold climates.* Its greater frequency after meals
and coition, during continued watchfulness, exercise,
or mental excitement, is universally known. (B)

117. The heart rather than the arteries is to be re-
garded as the source of these varieties.

Its action continues in this manner till death, and
then all its parts do not, at once, cease to act; but the
right portion, for a short period, survives the left.

For since the collapsed state of the lungs impedes
the course of the blood from the right side, and the
veins must be turgid with the blood just driven into
[Seite 70] them from the arteries, it cannot but happen that this
blood, driving against the right auricle, must excite it
to resistance for some time after the death of the left
portion of the heart.

118. This congestion on the right side of the heart
affords an explanation of the small quantity of blood
found in the large branches of the aorta. Weiss,* and
after him Sabatier, ascribe to this cause likewise the
comparatively larger size of the right auricle and
ventricle in the adult dead subject especially.

119. The motion of the blood is performed by these
two orders of vessels in conjunction with the heart. Its
celerity in health cannot be determined: for it varies
not only in different persons, but in different parts of
the same person. Generally, the blood moves more
slowly in the veins than in the arteries, and in the small
vessels than in the large trunks. But these differences
have been overrated by physiologists.

The mean velocity of the blood flowing into the
aorta, is usually estimated at eight inches for each pul-
sation, or at fifty feet in a minute.

120. Some have affirmed that the globules of the
cruor move more in the axis of the vessels, and with
greater rapidity, than the other constituents of the
blood. I know not whether this rests upon any
satisfactory experiment, or upon an improper appli-
cation of the laws of hydraulics; improper, because
[Seite 71] it is absurd to refer the motion of the blood through
living canals, to the mere mechanical laws of water
moving in an hydraulic machine. I have never ob-
served this peculiarity of the globules. My persuasion
is still more certain that the globules pass on with the
other constituents of the blood, and are not rotated
around their own axis, – that besides the progressive,
there is no intestine, motion in the blood; although in-
deed there can be no doubt that the elements of this
fluid are occasionally divided, where it is variously
impelled according to the different direction, division,
and anastomoses of the vessels.

121. The powers of the sanguiferous system are now
to be examined: first, those of the heart, by far the
greatest of all; afterwards, those which are only sub-
sidiary, though indeed highly useful.

122. That the powers of the heart cannot be accu-
rately calculated is clear, upon reflecting that neither
the volume of the blood projected at each pulsation,
nor the celerity nor distance of its projection, much
less the obstacles to the powers of the heart, can be
accurately determined.

123. A rough calculation may be made by taking
every probable conjecture together: v.c. if the mean
bulk of the blood is considered as 10 pounds, or 120
ounces; the pulsations 75 in a minute, or 4500 in an
hour; and the quantity of blood expelled from the left
ventricle at each contraction, as two ounces; it fol-
lows that all the blood must pass through the heart
75 times every hour. The impetus of the blood pass-
ing from the heart, may be conceived by the vio-
lence and altitude of the stream projected from a
large wounded artery situated near it. I have seen
[Seite 72] the blood driven to the distance of at least live feet
from the carotid of an adult and robust man.*

124. This wonderful, and, while life remains, con-
stant, strength of the heart, is universally allowed to
depend on its irritability, (41) in which it very far sur-
passes, especially as to duration, (98) every other
muscular part.

That the parietes of the cavities are excited to con-
traction by the stimulus of the blood, is proved by the
experiment of Haller, who lengthened at pleasure the
motion of either side of the heart, by affording it
the stimulus of the blood for a longer period than the
other.§ (C)

[Seite 73]

125. Since a supply of nerves and blood is requisite
to the action of the voluntary muscles, it has been
enquired whether these are requisite to the heart also.*

The great influence of the nerves over the heart, is
demonstrated by the size of the cardiac nerves, and
by the great sympathy between the heart and most func-
tions, however different. A convincing proof of this,
is the momentary sympathy of the heart during the
most perfect health with the passions, and with the
primae viae in various disorders. But the great import-
ance of the blood to the irritability of the heart, is evi-
dent from the great abundance of vessels in its mus-
cular substance.

Nevertheless it is very probable, that the importance
of the nerves in this respect is greater in the voluntary
muscles, and of the blood in the heart.

126. Besides these powers of the heart, there is ano-
ther, which is mechanical, dependent on structure, and
greatly contributing, in all probability, to sustain the
circulation. For when the blood is expelled from the
contracted cavities, a vacuum takes place, into which,
according to the common laws of derivation, the neigh-
bouring blood must rush, being prevented, by means
of the valves, from regurgitating. (D)

[Seite 74]

127. We must now enquire what powers are exerted
by other organs in assisting the circulation. The exist-
ence of some secondary powers and their ability to as-
sist, or even in some cases to compensate for, the
action of the heart, are proved by several arguments:
v.c. the blood moves in some parts to which the in-
fluence of the heart cannot reach, – in the vena portae
and placenta; not to mention instances of the absence
of the heart.*

128. The principal of these powers is the function of
the arteries, not easy indeed to be clearly understood
and demonstrated. 1. They have a muscular coat. (E)
2. That they are irritable, has been proved by repeated
experiments. 3. The size of the soft nerves arising
from the sympathetic, and surrounding the larger arte-
rial branches, particularly in the lower part of the
abdomen, argues the importance of these vessels in
assisting the motion of the blood.§

129. The arteries pulsate, and indeed violently, so
[Seite 75] that if, v.c. we place one leg over the other knee, we
find not only that it, but even a much greater weight,
may be raised by the pulsation of the popliteal. Hence
an alternate systole and diastole, corresponding with
those of the heart, have long been assigned to them.
But this, although commonly believed on the evidence
of sense, is open to much question:* it may be asked,
especially, whether this pulsation is referrible to the
power of the artery, or only to the impulse given by
the heart to the blood propelled into the aorta.

130. And indeed, after all, it appears that the dias-
tole
of an artery is owing to the blood, – to a lateral
distention given by the impetus of the blood, so that
the coats are expanded; and the vessel, by its elasti-
city, the next moment reacquires its natural thickness.
To the same impulse may be ascribed the lateral mo-
tion of the axis, observable in the larger arteries, if
serpentine and lying in loose cellular substance. (F)

The genuine systole, produced by a contraction of
their substance, scarcely occurs, probably, while the
heart acts with sufficient vigor; but when they are un-
usually stimulated, or if the action of the heart fails or
is impeded by severe disease, then indeed the arteries
may supply its place and propel the blood by their own
vital energy,

131. Since Whytt and other illustrious physiolo-
[Seite 76] gists have been convinced that the influence of the
heart could not reach the extreme arteries and the ori-
gins of the veins, they have ascribed the progression
of the blood in those vessels to a kind of oscillation,
and have happily employed this to demonstrate the
nature of inflammation. Many kinds of phenomena,
both physiological, as those regarding animal heat,
and pathological, as those observed in spasms and
particularly in fevers, favour the supposition of this
oscillatory faculty, though it is not demonstrable to
the eye. (G)

132. It remains now to enquire into the aid given to
the returning blood by the veins, not alluding at all to
their radicles. We should conclude at first sight that
they have less active power* than the rest of the san-
guiferous system, and that the return of their purple
blood to the heart is chiefly ascribable to the impetus
a tergo of the arterial blood, and to their valvular
structure which prevents any reflux. The efficacy
of the valves in this point of view, is shewn by the
distentions and infarctions of the veins in the lower
part of the abdomen, which are found destitute of
valves.

The existence of vital powers in the venous trunks
is probable, from the example of the liver and pla-
[Seite 77] centa (127), and from experiments instituted on living
animals. We formerly mentioned the muscular ap-
pearance in the extreme veins near the heart (95). (H)

133. These are the chief powers which move the
blood and depend upon the structure and vitality of the
sanguiferous system: we say nothing of the effect of
gravity, attraction, and other powers, common to all
matter. The more remote assistance derived after
birth from particular functions, v.c. respiration and
muscular motion, will appear in our account of those
functions.


NOTES.

(A) Dr. W. Hunter first accounted for this in 1746.

‘“The systole and diastole of the heart, simply, could not pro-
duce such an effect; nor could it have been produced, if it had
thrown the blood into a straight tube, in the direction of the axis
of the left ventricle, as is the case with fish, and some other
classes of animals: but by throwing the blood into a curved tube,
viz. the aorta, that artery, at its curve, endeavours to throw itself
into a straight line, to increase its capacity; but the aorta being
the fixed point against the back, and the heart in some degree
loose and pendulous, the influence of its own action is thrown
upon itself, and it is tilted forwards against the inside of the
chest.”’*

Dr. Barclay has the following passage on this point.

‘“When the blood is forced into the arteries, their curvatures,
near where they issue from the ventricles, are from their disten-
tion lengthened and extended towards straight lines; and, caus-
ing the heart to participate in their motions, compel it to describe
[Seite 78] the segment of a circle, when the apex moving atlantad and
sinistrad, is made to strike against the left side. The same kind
of motion having also been observed by the celebrated Haller, in
distending the left or systemic auricle, it must follow, that the
stroke which is given to the side, may be the effect of two distinct-
causes, either acting separately, or in combination; but acting
on a heart obliquely situated, as ours is, in the cavity of the
thorax, where the aspect of the base is atlantad and dextrad, and
that of the apex sinistrad and sacrad. In combination, as the
first of the two, by removing the pressure, will facilitate the in-
flux of the venous blood into the left or systemic auricle, which
is situated dorsad; so the second, by the influx of blood into the
auricle, will contribute in its turn to facilitate the circular motion
of the heart, proceeding from the arteries.”’*

(B) It is commonly believed, that the pulse of every person is
quicker in the evening than in the morning, and some have sup-
posed an increase of quickness also at noon. Upon these sup-
positions Cullen builds his explanation of the noon and evening
paroxysms of hectic fever, regarding them as merely aggrava-
tions of natural exacerbations. The existence of the noon pa-
roxysms is doubtful, and the evening one cannot be so explained,
if the writer of a paper in the Edinbugh Journal is correct.
His observations show the pulse to be slower in the evening,
and quicker in the morning.

(C) The heart, however, of frogs, for instance, contracts and
relaxes alternately, for a length of time, when out of the body
and destitute of blood.

(D) The influence of this vacuum first pointed out by
Dr. Andrew Wilson, and conceded by John Hunter, has been
lately very ably displayed by Dr. Carson of Liverpool.§

The quantity of the blood, the length of its course, and the
[Seite 79] various obstacles opposed to its progress, render it unlikely that
the mere propulsive power of the heart is sufficient to maintain the
circulation perpetually. But great assistance must be given by the
vacuum which takes place in all the cavities of the organ, when
the contraction of the muscular fibres is over. The blood is thus
drawn into each relaxed cavity, and the heart performs the double
office of a forcing and a suction pump. The rapid but quiet motion
of the blood in the veins is thus accounted for and would other-
wise be inexplicable. The situation of the valves of the heart is
also accounted for. There are valves between the auricles and
ventricles, and at the mouths of the two great arteries, because
behind each of these four openings is a cavity of the heart, alter-
nately dilating and affording a vacuum, into which, without
valves, the blood would be drawn retrograde. At the venous
openings of the auricles no valves exist, because they do not
open from a cavity of the heart, – from a part ever experiencing
a vacuum, and therefore the blood cannot, when the auricles
contract, move retrograde, but will necessarily pass forwards into
the ventricles, which at that moment are offering a vacuum.
The inferior elasticity and irritability of the veins are also ex-
plained. If veins were capable of contracting equally with arteries,
on the diminution of their contents, the suction influence of the
heart would constantly reduce their cavities to a smaller capacity
than is requisite for their functions. The collapse of the veins
by pressure, during the suction of the heart, is prevented by the
fresh supply of blood afforded by the vis a tergo, which does exist,
although it cannot be considered as of itself adequate to convey
the blood back to the right auricle. The reason appears why a
tied vein is emptied in the part nearest the heart; – its blood is
drawn forwards by suction. We see why a punctured vein does
not bleed, if there are other veins to convey the blood discharged
from the arteries. The puncture necessarily removes the suction
influence of the heart, and the great cause of the progress of the
blood in the vein is taken away, while it exists in full force in
the other veins of the limb. Were it not for this circumstance,
[Seite 80] a punctured vein should afford blood very readily. If the chief
vein of a limb is wounded, the blood will flow, because it re-
ceives the whole blood of the arteries, transmitted by the vis a
tergo, no other veins existing into which it can be drawn when
the vacuum occurs in the right auricle: what is a parallel circum-
stance, if all the veins of a limb are tied, they swell, whereas
the ligature of one causes no tumefaction in it. These circum-
stances are no proof that the vis a tergo is sufficient of itself to
bring back the blood, because it is certain that such a vacuum
exists, and that such must be the effects of this vacuum upon the
movement of the blood: the hemorrhage in the former instance,
and the tumefaction in the latter, show a certain force only in the
blood, which, were it even sufficient to bring the blood back to
the heart, as an experiment of M. Majendie’s almost proves it to
be,* would not probably long continue so after the assistance of
suction was removed.

From the structure of the heart it is clear that the mere alter-
nate relaxation of its parietes enlarges its cavities and forms a
vacuum. Experiment proves the same. Dr. Carson put the hearts
of some frogs just extracted into water, blood-warm. They
were thrown into violent action, and, upon some occasions, pro-
jected a small stream of a bloody colour through the transparent
fluid. It was thought that a stream of the same kind continued
to be projected at every succeeding contraction; but that, after
the first or second, it ceased to be observable, in consequence of
the liquid supposed to be imbibed and projected, losing its
bloody tinge and becoming transparent, or of the same colour
with the fluid in which the heart was immersed. The organ was
[Seite 81] felt by the hand to expand during relaxation. He accounts,
however, for the full dilatation of the heart upon another prin-
ciple, upon which it will be impossible to enter at lengh before
the next section.

(E) Most Physiologists grant to the capillaries irritability, to-
nicity, or organic contractility; but some deny that arteries pos-
sess muscular properties. Bichat’s objections are, the absence
of contraction on the application of stimuli to them, the much
greater resistance of the middle coat to a distending force than
of muscular parts, and, lastly, the difference of the changes
which it and muscles undergo both spontaneously and by the
action of other substances.* Berzelius has multiplied the latter
description of proofs. However this may be, they have cer-
tainly vital powers of contraction as fully as any parts of the
body. This appears in their various degrees of local dilatation
and contraction, under inflammation, passions of the mind, &c.:
and if the capillaries alone are allowed to possess organic contrac-
tility, it is impossible to say in which point of the arterial track
it begins.

Dr. Parry has instituted a number of experiments upon this
question. After exactly ascertaining the circumference of arte-
ries in animals, he killed them and again measured the circum-
ference; and after the lapse of many hours, – when life must have
been perfectly extinguished, he measured the circumference a
third time. Immediately after death, the circumference was
found greatly diminished, and on the third examination, it had
increased again. The first contraction arose from the absence of
the blood which distended the vessel and antagonised its efforts
to contract, and it was evidently muscular, or to speak more
correctly, organic, contraction, because, when vitality had ceased
and this kind of contraction could no longer take place, the
vessel was, on the third examination, always found enlarged.

The forced state of distention in arteries was proved by the
[Seite 82] contraction immediately occurring on making a puncture in a
portion of vessel included between two ligatures. The capacities
of arteries are thus always accommodated to the quantity of
blood, and this circumstance gives the arterial canal such pro-
perties of a rigid tube as enable an impulse at the mouth of the
aorta to be instantly communicated throughout the canal. This
appears the great office of the contractile powers of arteries, for,

(F) They do not incessantly dilate and contract as many ima-
gine. Dr. Parry, on the most careful examination, could never
discover the least dilatation in them, during the systole of the
ventricle, – when the pulse is felt. He very properly remarks,
that the pulse is felt only when arteries are more or less com-
pressed; under which circumstance, the motion of the blood
onwards, by the impulse of a fresh portion from the left ven-
tricle, is impeded: and this effort of the fluid against the ob-
structing cause gives the sensation called the pulse.*

Dr. Curry, the late senior physician and highly distinguished
lecturer on the practice of medicine at Guy’s Hospital, concluded,
without doubt hypothetically, from some microscopic experi-
ments which he made on inflammation in the presence once of
Mr. Charles Bell and once of Mr. Travers, that the circulation
is indispensably facilitated by a sort of electric repulsion between
the vessels and their contents, and that in inflammatory accu-
mulation, the tone of the vessels being impaired, this repulsion
is diminished and the blood passes onwards with difficulty in
consequence. My friend and colleague Dr. Scott has obliged
me with ample notes taken by himself some years ago, but any
one may see in the edition of Dr. Curry’s Syllabus, printed in 1810,
page 66, the paragraph in which inflammation is referred to the
[Seite 83] neuro-electric state of the vessels, and which contains all the heads
of the detail. Mr. Charles Bell has lately published this hypothesis
as his own,* but most of the facts adduced by him to prove that
the resistance to the blood’s progress is removed by a repul-
sion between it and the vessels may be explained by the suction
influence of the heart which he altogether overlooks.

(G) These oscillations are quite imaginary and now disallowed.
Although variations of dilatation must affect the course of the
blood through vessels, it is difficult to conceive how any regular
action of them can assist it.

(H) In a young lady whom I lately attended for chronic ca-
tarrh accompanied by violent cough, from which she ultimately
recovered, all the veins of the back of the hands and fore-arms
distinctly pulsated synchronously with the arteries.


The heart of mammalia and birds has no peculiarity necessary
to be mentioned here. In most amphibious animals, the arteries
spring from the right ventricle, with which the left, that sends off
no vessel, communicates: hence their circulation continues under
water. The heart of fish is extremely small, and has but one au-
ricle and ventricle, the latter propelling the blood to the gills, from
which it streams through a large artery. Neither blood vessels
nor absorbents have been discovered in insects; yet a large tube,
close at each end, pulsates in their back. With respect to the
mollusca: The cuttle fish has three detached hearts, consisting of a
ventricle only, two for the gills and one for the aorta; the rest have
a single heart, the blood of the cava passing through the gills
before it reaches the heart. The same is the case with the crus-
tacea,
and their heart has no auricle. Worms have circulating
vessels distinctly contracting and dilating, but no heart. Zoo-
phytes
have no heart, nor circulating system, properly so called.
In the echinus indeed there are two vessels that run along the
intestines and are thought to be an aorta and vena cava.

SECT. VIII.
OF RESPIRATION AND ITS PRINCIPAL USE.

[Seite 84]

134. The lungs,* closely connected with the heart
both by proximity and by relation of function, are two
viscera, large after birth, so light as to swim in water,
and composed of a spongy, and, as it were, spumous,
but pretty tenacious, parenchyma.

135. They fill each cavity of the chest, and are con-
tiguous to the sacs of the pleurae, to which, as well as
to the other contents of the thorax, they model and
apply themselves. (A)

136. They, in a manner, hang from the wind-pipe
usually called the aspera arteria, which, besides its
interior coat always smeared with mucus, and the sub-
jacent very sensible nervous coat, consists of another
which is muscular, surrounding the latter, and divided,
except posteriorly, by an indefinite number of cartila-
ginous falciform arches.

137. The aspera arteria, having entered the thorax,
is bifurcated into the two bronchiae, and these, the
more deeply they penetrate into the lobes and lobules
of the lungs, are the more and more ramified, losing
[Seite 85] both their cartilaginous rings and muscular coat, until
their extreme divisions terminate in those cells which
form the chief part of the substance of the lungs and
alternately receive and emit the air we breathe.

138. The shape and magnitude* of the air cells are
various. The former is generally polyedrical. The
latter, in regard to surface, is scarcely to be defined:
though, indeed, the capacity of the lungs of an adult,
during a strong inspiration, is about 120 cubic inches.
The immense size to which the lungs may be inflated,
when the chest has been opened, has no relation to our
present subject.

139. The cells are invested and connected by the
common but delicate mucous web, – the general vincu-
lum of the body, and must be carefully distinguished
from it. In healthy and very recent lungs, I have found
the cells so unconnected that they were distended in
one insulated spot by air cautiously inflated into a fine
branch of the bronchiae, while neither the neighbouring
cells nor the cellular membrane, which lies between
the cells, admitted a single portion. If air is forcibly
thrown in, the air cells are ruptured and confounded
with the cellular membrane, and both parts distended.

140. The mucous web surrounding the air cells of
the lungs is supplied with innumerable blood vessels –
divisions of the pulmonary artery and four pulmonary
veins, the branches of which accompany the ramifica-
tions of the bronchiae, and, after repeated division,
[Seite 86] form at length a most delicate and immense collection
of reticulated anastomoses. This extraordinary net-
work, penetrating the mucous web on every side,
closely surrounds the air cells, so that the prodigious
quantity of blood existing in the pulmonary vessels is
separated from the contact of the air by very fine mem-
branes only which Hales estimated as scarely 1/1000 of
an inch in thickness.

141. As each ramification of the bronchiae possesses
a peculiar bunch or lobule of air cells, (139) so again
each of these possesses a peculiar system of blood
vessels, the twigs of which anastomose in the net-work
with one another, but scarcely at all with the blood-
vessels of the other lobules, as is proved by micros-
copic observations on living frogs and serpents, by
minute injections, and by the phenomena of vomicae
and other local diseases of the lungs.

142. The common membrane investing the lungs
is the chief seat of a remarkable net-work of lymphatic
vessels* which run to numerous lymphatic or conglo-
bate glands, carefully to be distinguished from a
neighbouring order of glands, called bronchial, that
are supplied with an excretory duct and are of the
conglomerate kind.

143. The thorax, which contains the lungs, has an
osseous and cartilaginous base, somewhat resembling
a bee-hive, throughout very firm and stable, but in
every part more or less moveable for the purpose of
respiration.§

[Seite 87]

This holds good chiefly with the six pairs of true ribs
below the first pair, each of which is more moveable
than the one above in proportion to the greater length
both of its own body and of its cartilaginous appendix.
The cartilages are united by a kind of amphiarthrosis
to the margin of the sternum on each side. (B)

144. Between the edges of the ribs lie two strata of
intercostal muscles, differing in the direction of their
fibres, but conspiring to produce the same motion.

At the base of the thorax, the diaphragm* is sub-
tended in the form of an arch. It is a considerable
muscle, and, in the words of Haller, next in importance
to the heart. Its utility in the mechanical part of res-
piration was long since shewn, by the excellent expe-
riments of Galen upon living animals, to depend
chiefly on the phrenic nerve.

Its antagonists are the abdominal muscles, especially
the two oblique and the transverse.

145. The thorax thus constituted, is, after birth,
dilated by inspiration and subsequently reduced to a
smaller capacity by expiration.

During the former act, the thorax is enlarged late-
[Seite 88] rally and inferiorly, so that the bodies of the six ribs
mentioned above (143) are elevated and their inferior
margin drawn somewhat outwards, and the arch of
the diaphragm at the same time rather depressed and
flattened.

I have never observed the inferior extremity of the
sternum, in tranquil respiration, to be thrust forwards,
as some have asserted. (C)

146. This alternate motion of the chest continues,
during health and freedom from restraint, from the
hour of birth till death. Its object is, that the lungs
may be expanded to admit the air and contracted to
expel it, in perpetual alternation. This alternation
occurs, in an adult at rest, about 14 times in a minute,
– once to about five pulsations of the heart.

147. For man, in common with all warm-blooded
animals, cannot long retain the inspired air, but is
compelled to discharge it and take in a fresh supply
of this pabulum of life, as it always has been denomi-
nated.* Common observation teaches, that however
pure may be the air entering the lungs, it instantly
undergoes remarkable changes, by which it is con-
taminated and rendered unfit for another inspiration,
unless it is renewed.

[Seite 89]

148. It may be asked what are the changes which
the air experiences during inspiration, and which con-
sist not in the loss of elasticity, as was formerly
imagined, but in the decomposition of its elements.*
For the atmospheric air which we breathe, is a singular
mixture of constituents, differing very much in their
nature from each other; and, not to mention hetero-
geneous matters, such as odorous effluvia, various
exhalations, and innumerable others which are gene-
rally present, is always impregnated with aqueous
vapour, electric and magnetic matter, and generally
with carbonic acid gas; and is itself composed of
unequal parts of two aëriform fluids, viz. 79 of azotic
gas, and 21 of oxygen gas in 100.

149. In the first place we know for certain, that at
every inspiration (the fulness of which varies infinitely
in different men of the same age, breathing placidly),
besides the quantity of azotic gas being somewhat
diminished, the oxygen gas is in a great measure
converted into carbonic acid gas, or fixed air; so that
the air of expiration, if collected, instantly extinguishes
flame and live coals, precipitates lime from lime water,
and is specifically heavier than atmospheric air, and
rendered unfit for respiration;§ it also contains much
[Seite 90] aqueous vapour, which is condensed in a visible form
by a temperature of 60° of Fahr.*

150. It is therefore probable, that, during inspira-
tion, the base of the oxygenous portion is set at liberty,
and, being united with the arterial blood, is conveyed
throughout the system; while the carbon and hydrogen
are brought back with the venous blood to the right
side of the heart, and thrown off like smoke, as the
ancients expressed it, in the lungs.

The more florid colour of the arterial blood, the
darker of the venous, and the analogous appearance of
the blood, if exposed to the gases in question, (13)
correspond admirably with this theory. Some diffi-
culties, indeed, remain to be solved, v.c. how the
carbon can be united in the lungs with the oxygen, so
as to fly off in the form of carbonic acid gas. (C)§

151. This perpetual change of elements occurring in
[Seite 91] respiration after birth, we shall show to be very diffe-
rently accomplished in the foetus, viz. by means of the
connection of the gravid uterus with the placenta.
But when the child is born and capable of volition, the
congestion of blood that takes place in the aorta, from
the obstruction in the umbilical arteries; the danger of
suffocation from the cessation of those changes of the
blood, in regard to oxygen and carbon, (13) hitherto
produced in the uterine placenta; the novel impression
of that element into which the child, hitherto an aquatic
being, is conveyed; the cooler temperature to which it
is now exposed; and the many new stimuli which are
now applied, seem to induce new motions in the body,
especially the dilatation of the chest and the first
inspiration.

The lungs being for the first time dilated by inspi-
ration, open a new channel to the blood, so that,
being obstructed in the umbilical arteries, it is derived
to the chest.

Since the inspired air becomes hurtful and unplea-
sant to the lungs by the decomposition which it expe-
riences, I should ascribe to the most simple corrective
powers of nature, the subsequent motion by which the
poisonous mephitis, as it may be called, is expelled
and exchanged for a fresh supply.

The consideration of all these circumstances, espe-
cially if the importance of respiration to circulation,
demonstrated by the well-known experiment of Hooke,*
[Seite 92] be remembered, will, in my opinion, explain the cele-
brated problem of Harvey* better than most other
attempts of physiologists. (D)


NOTES.

(A) A correct notion can scarcely be formed from this descrip-
tion. The pleura is two closed sacs, one of which lies over each
lung, one portion of the sac adhering closely to it, and one lying
over this again; the internal surfaces of both portions are always
in contact, because, if the parietes of the thorax expand and
draw with them the external portion, the lung at the same time
expands with air and forces out the internal in the same degree.
It is commonly said that a portion of fluid (not vapour) exists
in serous membranes for the purpose of lubrication. The late
Dr. Marshal, however, proved that this is not the case, but that
whenever fluid is discovered, we must regard it as the effect of
either disease or the struggle of dying. His experiments were
made on the ventricles of the brain, the theca vertebralis, the
pleura, and the pericardium.§

These membranes during life and health are transparent. At
least M. Richerand tells us that on removing a portion of the
[Seite 93] thorax when cutting away a cancer, he saw the heart through
the pericardium.*

(B) Although each lower rib must execute a greater extent of
motion from being longer than the one above, yet the first is
asserted by M. Majendie to be absolutely more moveable than
the second, the second than the third, &c.: and this because the
first has but one articular surface, is articulated with but one
vertebra, and possesses neither internal nor costo-transverse liga-
ment, and has the posterior ligament horizontal, and because
slight shades of difference exist in the disposition of the liga-
ments of the six other ribs.

(C) To Dr. Carson we are indebted for the best account of
the mechanical part of respiration.

The substance of the lungs is highly elastic, and constantly
kept in a forced state of distention after birth by the pressure of
the atmosphere. This is evident, as upon puncturing the walls
of the thorax, the lungs instantly collapse, – a circumstance
arising from the atmospheric pressure on the one hand becoming
counterbalanced on the other, so that their elasticity, expe-
riencing no opposition, becomes effective. During inspiration,
the intercostal muscles raise and draw out the ribs, and the dia-
phragm descends: the enlargement of the thoracic cavity is
instantly followed of necessity by the greater distention of the
substance of the lungs from the diminished resistance to the
atmosphere gravitating in the bronchiae. The diaphragm and
intercostal muscles ceasing to act, the substance of the lungs
exerts its elasticity with effect, recovers its former dimensions,
and drives out the additional volume of air just admitted, and
the passive diaphragm and intercostal muscles follow the shrink-
ing substance of the lungs, offering, from their relaxation, no
resistance to the atmosphere pressing on the surface of the chest
and abdomen. Thus expiration is produced. The muscular
[Seite 94] power of the diaphragm and intercostal muscles is far greater
than the elastic power of the lungs, and therefore, when exerted,
overcomes it, producing inspiration: but, ceasing to be exerted,
the elastic power gains efficiency, and produces expiration.
‘“The contractile power of the diaphragm (and intercostal
muscles
) in conformity with the laws of muscular motion, is irre-
gular, remitting and sometimes altogether quiescent. The elas-
ticity of the lungs, on the other hand, is equal and constant.
The superior energy of the former is balanced by the permanency
of the latter. By the advantage which the inferior power, from
the uniformity of its operations, is enabled to take of the remis-
sions of its more powerful antagonist, the ground which had
been lost is recovered, and the contest prolonged; that contest
in which victory declaring on one side or the other is the instant
death of the fabric.”’*

In the common account of respiration, the elasticity of the
lungs is unnoticed, and expiration is ascribed to the contractions
of the abdominal muscles. Now in the first place, the elasticity
of the lungs is of itself sufficient for the purpose; and in the
second, there is no proof of the agency of these muscles in
expiration. It proceeds equally well in cases of inanition, when
their contraction would rather enlarge than diminish the abdo-
minal cavity, and in experiments when they are entirely removed
from animals.

The beautiful contrivance in the shape of the thorax deserves
attention: by its being conical, every degree of motion in the
diaphragm produces a greater effect on the capacity of the chest
than could occur were it of any other shape.

The vacuum constantly threatening in the chest, either from
the shrinking of the lungs or the contraction of the inspiratory
muscles, and I may add from the expulsion of blood from the
ventricles of the heart, will evidently be prevented, not only by
the falling of the ribs and the ascent of the diaphragm in the
[Seite 95] former case, and ingress of additional air into the bronchiae in
the latter, but also by the flow of venous blood into the auricles:
for the venous blood, being subject to the full atmospheric pres-
sure without the chest, will necessarily be driven into the chest
to prevent a vacuum; the arterial blood is under the same cir-
cumstances, but the propelling force of the ventricles prevents
its retrogression. The atmospheric pressure on the blood-vessels
creates a necessity for greater strength in the ventricles, as it
impedes the progress of blood from the heart, but it also faci-
litates the return. Thus the smaller pressure on the heart acts,
by the intervention of the blood, as an antagonist to its con-
tracting fibres, assisting to dilate them when they become relaxed.

By the tendency to a vacuum in the cavity of the thorax, what
effect the heart loses by atmospheric resistance without the chest
is exactly compensated within, and thus on the whole the heart
neither gains nor loses by all the various directions of atmos-
pheric pressure.

In the foetus the case is precisely the same, although Dr. Carson
has imagined it different, and thought it necessary to frame a
little hypothesis to reconcile circumstances. The foetal lungs,
experiencing no atmospheric pressure, are contracted to the
utmost, and the diaphragm suffering no stimulus from the will
on account of uneasy sensation arising from want of breath, is
completely relaxed and forced upwards, to remove the vacuum,
and the venous blood without the thorax must, for the same rea-
son, be drawn forcibly into the right auricle, preventing the
vacuum which the shrunk state of the lungs, and the discharges
of blood from the left ventricle, tend to produce.

The cause of the first inspiration appears to be the novel im-
pression of cool air upon the surface, for if at any time we are
suddenly exposed to a cold wind or plunge into cold water, the
diaphragm and intercostal muscles instantly contract and a quick
inspiration takes place. The blood rushes into the expanded
lungs, and being afterwards obstructed when the inspiratory
muscles cease to act, and the elastic lungs shrink, gives rise to
[Seite 96] an uneasy sensation, which is instinctively removed by another
inspiration, and thus respiration afterwards continues through
life. The fact of respiration commencing before the chord is
tied, shows that neither the congestion in the aorta, nor the
deficiency of chemical changes, is the cause of the first
inspiration.

The elasticity of the lungs is not sufficiently great to expel
the whole of their air in expiration, whence they remain con-
stantly in a certain degree of distention, and the course of the
blood through them is never completely obstructed by expiration.

(D) It is now ascertained, that no oxygen is absorbed in ordi-
nary respiration, but that what disappears goes entirely to unite
with the carbon of the blood and produce carbonic acid, the
latter being exactly equal in bulk to the oxygen that disappears, –
about 27 1/2 cubic inches per minute, or 39,534 in 24 hours,
according to the experiments of Messrs. Allen and Pepys, – a
quantity containing about 11 oz. troy of solid carbon, and per-
haps about double the average result of most other experiments.
Mr. Ellis* contends that the carbon escapes from the vessels
and unites with the oxygen externally, and Dr. Prout thinks
this opinion corroborated by a fact stated by Orfila, – that when
phosphorus dissolved in oil is injected into the blood vessels,
vapours of phosphorous acid stream from the mouth and nos-
trils, which would hardly have occurred if the acid had been
formed in the vessels, as it would probably have remained in
solution in the blood, not being volatile: – the phosphorus was
probably excreted from the vessels in minute subdivision, and
united with the oxygen of the atmosphere upon coming in con-
tact with it, producing phosphorous acid; and the same may
be imagined respecting the carbonic. Allen and Pepys ob-
served that if respiration of the same air was breathed repeatedly,
some oxygen was absorbed; and that if nearly pure oxygen was
[Seite 97] employed in the case of guinea-pigs, pure carbonic acid was
produced and a portion of the oxygen replaced by nitrogen, this
portion, however, decreasing as the experiment proceeded. The
use of the nitrogen that we respire is unknown.

The universality of respiration or something analogous among
living beings,* and all the circumstances attending its perform-
ance, render it probable, as my friend Dr. Prout justly remarks, that
it does something more than discharge a little superfluous carbon.
He considers galvanism as an instrument extensively used by the
vital principle, and since galvanism must be produced by the
combination of carbon with oxygen, as it is in the battery by
the union of the metal and oxygen, one great additional purpose
of respiration becomes highly probable.

Dr. Prout and Dr. Fyfe have found the quantity of carbonic
acid gas experience uniform variations. It is diminished by
mercury, nitric acid, vegetable diet, tea, substances containing
alcohol, depressing passions, and fatigue, and undergoes an
increase from day-break till noon, and a decrease from noon
till sun-set, remaining at the minimum till day-break. In the
experiments of Allen and Pepys, the formation of carbonic acid
gas slackened when the guinea-pigs fell asleep.

[Seite 98]

The average number of respirations in a minute in adults is
probably twenty.

The common quantity of air taken in at each inspiration is 16.5
cubic inches, and the quantity remaining after death in the lungs
of a stout adult man, about 100 cubic inches, according to Allen
and Pepys.

The quantity of aqueous vapour emitted by the lungs in expi-
ration may be about 20 oz. in 24 hours.*

Camphor, phosphorus, ether, diluted alcohol, gases, and va-
rious odorous substances, when introduced into the system escape
in some measure by the lungs.

(E) The experiment consisted in laying the lungs completely
bare, and supporting life by carrying on respiration artificially.
Hooke varied it by pricking the surface of the lungs and forcing
a continued stream of air through them. The following are the
words of Harvey: ‘“It would appear that the use of expiration
is to purify and ventilate the blood, by separating from it these
noxious and fuliginous vapours.”’

SECT. IX.
OF THE VOICE AND SPEECH.

[Seite 99]

152. We have described the chief use of respiration.
We shall hereafter mention how far it contributes to the
conversion of the chyle into blood, and to the support
of almost the whole class of natural functions. Its
other uses are at present to be considered.

And first, respecting the voice.* This takes place
after birth, and proceeds from the lungs, as was ob-
served long ago by Aristotle, who called those animals
only vocal, which breathed by means of lungs. The
voice is, properly speaking, a sound, formed, by means
of expiration, in the larynx, which is a most beauti-
fully constructed organ, fixed upon the top of the
windpipe, like a capital upon a pillar.

153. The larynx is composed of various cartilages,
which being united together in the form, as it were,
of a little box, and supplied with a considerable and
wonderful apparatus of muscles,§ may be moved alto-
gether, or separately, according to the variations of
the voice.

[Seite 100]

154. The part of the larynx most concerned in pro-
ducing the voice, is the glottis, or narrow opening of
the windpipe, having the epiglottis suspended, and, in
a manner, fixed upon it. It is clearly ascertained, that
the air, expired from the lungs, and striking properly
upon the margins of the glottis, becomes sonorous.

155. But it has been disputed what changes the
glottis undergoes in modulating the voice: whether it
is alternately widened and constricted, as Galen and
Dodart supposed, or whether, according to Ferrein,
the variations of voice are effected rather by the tension
and relaxation of its ligaments.

The latter, consistently with his opinion, compared
the larynx to a violin; the former, more consistently
with nature, to a flute.*

Every thing considered, we must conclude that the
glottis, when sounding, experiences both kinds of
changes; since the grave and acute modulation of the
voice must depend very much upon the alterations
produced in the glottis by the ligaments, especially the
inferior thyreo-arytenoids – the vocal chords of Ferrein,
and by the corresponding modification of the sinuses or
ventricles of the larynx.

156. That every degree of motion in the glottis is
directed by the numerous muscles of the larynx, is
[Seite 101] proved by the beautiful experiment of tying or dividing
the recurrent nerves, or par vagum,* and thus weaken-
ing or destroying the voice of the animal. (A)

157. Man and singing birds have the power of
whistling. In the latter, it is accomplished by a larynx
placed at each extremity of the wind-pipe and divided
into two portions. The former, though possessing a
single and undivided larynx, has only learned, I ima-
gine, to imitate birds by the coarctation of his lips.

158. Singing, which is compounded of speech and an
harmonic modulation of the voice, I conceive to be
peculiar to man and the chief prerogative of his vocal
organs. The power of whistling is innate in birds;
many of them may easily be taught to pronounce
words, and instances have been known of this even in
dogs. But it is recorded, that genuine singing has
once or twice only, and then indeed but indifferently
and with the utmost difficulty, being taught to parrots;
while, on the other hand, scarcely a barbarous nation
exists, in which singing is not common.

[Seite 102]

159. Speech is a peculiar modification of the voice,
adjusted to the formation of the sounds of letters by
the expiration of air through the mouth or nostrils, and
in a great measure by the assistance of the tongue,
applied and struck against the neighbouring parts, the
palate and teeth in particular, and by the diversified
action of the lips.* (B)

The difference between voice and speech is there-
fore evident. The former is produced in the larynx;
the latter by the singular mechanism of the organs
above described.

Voice is common to both brutes and man, even
immediately after birth, nor is entirely absent in those
wretched infants who are born deaf. But speech fol-
lows only the culture and employment of reason, and
is consequently, like it, the privilege of man in dis-
tinction to the rest of animal nature. For brutes,
natural instinct is sufficient: but man, destitute of this
and other means of supporting his existence inde-
pendently, enjoys the prerogative of reason and lan-
guage; and following, by their means, his social des-
tination, is enabled to form, as it were, and manifest
his ideas, and to communicate his wants to others, by
the organs of speech.

160. The mechanism of speech and articulation is
[Seite 103] so intricate and so little understood, that even the
division of letters and their distribution into classes*
is attended with much difficulty.

The division, however, of Ammann, into vowels,
semi-vowels, and consonants, is very natural:

I. He divides the vowels into simplea, e, i, y, o, u,
and mixed – ä, ö, ü.

These are formed by merely the voice.

The semi-vowels and consonants are articulated by
the mechanism of speech.

II. The semi-vowels are nasalm, n, ng (n before g,
which is nearly related to it), that is, the labio-nasal m,
the dente-nasal n, and the gutture-nasal ng; or oral
(lingual) – r, l, that is, r with a vibration of the tongue,
or l with the tongue less moved.

III. The consonants are distinguished into hissing
(pronounced in succession)-h, g, ch, s, sch, f, v, ph,
that is h, – formed in the throat, as it were a mere aspi-
ration; g and ch – true consonants; s, sch, – produced
between the teeth; f, v, ph, – formed by the applica-
tion of the lower lip to the upper front teeth: and
explosive (which are, in a manner, at once exploded,
by an expiration, for some time suppressed or inter-
[Seite 104] rupted) that is, k, q, – formed in the throat; d, t, – about
the teeth; p, b, – near the lips; and double (com-
pound) – x, z.

161. We must just mention certain other modifica-
tions of the human voice, of which some, as hiccup
and cough, belong more properly to pathology than to
physiology, but are very common in the most healthy
persons; and others, as weeping and laughing, appear
peculiar to the human race.

162. Many of these are so closely allied, as fre-
quently to be converted into each other; most also are
variously modified.

In laughter there is a succession of short and abrupt
expirations.*

Coughing is a quick, violent, and sonorous expira-
tion, following a deep inspiration.

Sneezing, generally the consequence of an irritation
of the mucous membrane of the nostrils, is a violent
and almost convulsive expiration, preceded by a short
and violent inspiration.

Hiccup, on the contrary, is a sonorous, very short,
and almost convulsive, inspiration, excited by an un-
usual irritation of the cardia.§

In weeping there are deep inspirations, quickly alter-
nating with long and occasionally interrupted expi-
rations.ǁ

[Seite 105]

Sighing is a long and deep inspiration, and the
subsequent expiration is sometimes accompanied by
groaning.*

Nearest in relation to sighing is gaping, which is
produced by a full, slow, and long, inspiration, followed
by a similar expiration, the jaws at the same time
being drawn asunder, so that the air rushes into the
open fauces and the Eustachian tubes. It occurs from
the blood passing through the lungs too slowly; v.c.
when the pressure of the air is diminished, as upon
very high mountains. A peculiar feature of gaping is
the propensity it excites in others to gape likewise;
arising, no doubt, from the recollection of the pleasure
it produced. (C)


NOTES.

(A) M. Le Gallois ascertained that the division of the recur-
rent nerves frequently proves even fatal to animals. This effect,
however, varies with the species and age. The danger dimi-
nishes as the animal is older; and, after a certain age, little
inconvenience follows, because the (anterior part of the ?) open-
ing of the glottis is larger proportionally to the capacity of the
lungs not merely in some species than others, but in old than
in young animals.

The inferior ligaments of the glottis are the chief seat of the
[Seite 106] voice, for in blowing into the trachea and larynx of an animal a
slight sound only is heard, unless you approximate the arytenoid
cartilages to each other, when a sound somewhat analogous to
the voice of the animal will be produced, and more acute in pro-
portion to their approximation, and it will be seen, at the same
time, that the sound is caused chiefly by the vibrations of the
inferior ligaments of the glottis. Again, an opening below the
inferior ligaments destroys the voice, while one above it, even
through the epiglottis, superior ligaments, and arytenoid carti-
lages, has no such effect. In grave tones, the whole length of
the inferior ligaments may be seen in a dog to vibrate; in more
acute, the posterior part only; and in very acute, merely the
arytenoid extremity, the opening of the glottis being of course
lessened in the same proportion. These circumstances depend
upon the thyro-arytenoid muscles, which run on each side from
the arytenoid to the thyroid cartilage and form the lips of the
glottis (and indeed also the superior ligaments,) covered by an
aponeurosis, and this again by the mucous membrane. In pro-
portion as these contract, they become shorter and more tense,
and lessen the mouth of the glottis; but the complete closure
of the glottis at the back part is effected by the arytenoid muscle,
which connects the two arytenoid cartilages. As all these are
voluntary muscles, the division of their nerves destroys the
voice. The division of the recurrents, which supply the thyro-
arytenoid muscles, is sufficient for this purpose but, in some
instances, a sound still remains similar to what may be pro-
duced after death by blowing through the larynx after approxi-
mating the arytenoid cartilages, and must be owing to the action
of the arytenoid muscle, which is supplied not by the recurrent
but by the superior laryngeal nerves. As this muscle is the chief
means of contracting the posterior part of the glottis and pro-
ducing the most acute sounds, the division of the superior laryn-
geal nerves destroys almost all acute sounds and renders the
voice grave. When the division of the recurrent nerves proves
[Seite 107] fatal, it does so by paralysing the muscles that dilate the glottis,
for the arytenoid muscle that closes the back part of it, being
supplied by the superior laryngeal, acts unopposed.

‘“It is therefore evident that the larynx represents a reed with
two plates, the tones of which are acute in proportion as the
plates are short, and grave in proportion as they are long. But
although this analogy is just, we must not imagine that there is
a perfect identity. In fact, common reeds are composed of
rectangular plates fixed on one side and free on the three others,
while the vibrating plates of the larynx, which are also nearly
rectangular, are fixed on three sides and free on one only.
Besides, the tones of common reeds are made to ascend or
descend by varying their length; but the plates of the larynx
vary only in breadth. Lastly, the moveable plates of the reeds
of musical instruments cannot, like the ligaments of the glottis,
change every moment in thickness and elasticity.”’ The changes
in both the length and breadth of the trachea and of the cavity
between the glottis and the lips, and in the state of the epiglottis
and the ventricles of the larynx, must affect the voice.*

(B) I am indebted to the tremendously powerful Conyers
Middleton for the knowledge of two cases of distinct articula-
tion with at least but little tongue. In his exposure of the
difference between the pious deceptions of weak and wicked
Christians during the first centuries and the sublime miracles of
Christ. and his apostles, he notices a pretty tale of an Arian
prince cutting out the tongues of some of the orthodox party and
these being as able to talk as before; nay one (O hominum im-
pudentia!) who had been dumb from his birth, gained the faculty
of speech by losing his tongue. Granting the fact, and even
that the tongues were completely extirpated, he refers, for the
purpose of proving there was no miracle in the case, to two
[Seite 108] relations of similar instances by medical men in the Mémoires
de l’Academie des Sciences,
p. 6. 1718. Professor Thomson
found the speech little impaired after the bullets had carried away
more or less of the tongue.* Louis, Richter, Huxham, Bartholin,
Tulpius, it seems, mention similar cases. An instance of good
articulation after the loss of the apex and body of the tongue
quite down to the os hyoides occurred in this country.

SECT. X.
OF ANIMAL HEAT.

[Seite 109]

163. Man, the mammalia, and birds, are distin-
guished by the natural temperature* of their bodies
greatly exceeding that of the medium in which they are
accustomed to exist. Man is again distinguished from
these classes of animals by possessing a much lower
temperature than they; so that in this climate it is
about 96° of Fahr. while in them, and especially in
birds, it is considerably higher.

164. This natural temperature in man, is so con-
stant, equable, and perpetual, that, excepting slight
differences from variety of constitution, it varies but
little even in the coldest climate and under the torrid
zone. For the opinion of Boerhaave, – that man can-
not live in a temperature exceeding his own, has been
refuted, since the admirable observations§ of H. Ellis,
[Seite 110] the celebrated traveller and formerly the captain of the
George, by the remarkable experiments* of many
excellent physiologists. This striking prerogative of
man is evinced by his being restricted to no climate,
but inhabiting every part of the earth from Hudson’s
bay, where Mercury freezes, and from Nova Zembla,
to the scorching shore of Senegal.

165. The explanation of this circumstance is equally
simple and natural, and founded on the doctrine which
makes the lungs the grand receivers or focus, and
the decomposition of the oxygenised portion of the
air (148) the source or fomites, of our heat.

166. For, as the oxygenous part of the inspired air
is decomposed in the air-cells of the lungs, in such a
way that its base, which by its union with latent caloric
was before aëriform, now separates from this caloric,
it would appear that, by this decomposition, one por-
tion of the caloric is rendered sensible in the bronchiae,
while the other enters in a latent form into the blood,
circulating in the innumerable and delicate net-works
of the pulmonary vessels.

167. When the oxygenised blood thus charged with
latent heat circulates through the aortic system, it
acquires carbon in the small vessels and sets free much
[Seite 111] of the latent heat which it had received: in this way is
our animal heat principally produced.*

168. Its production and regulation, however, appear
much influenced by the secretion of fluids from the
blood, both those which are liquid and destined to
solidify by assimilation and nutrition, and those which
are permanently elastic.

169. Since those changes are effected by the energy
of the vital powers, the great influence of these upon
our temperature must be easily perceived.

170. Many arguments render it probable, that the
action of the minute vessels, and the conversion of
oxygenised into carbonised blood, are dependent
upon the varied excitement or depression of the vital
principle.

For the remarkable phenomena of the stability of
our temperature, (proved by the thermometer, and not
by the sense of touch, which may be fallacious) – that
[Seite 112] it is scarcely increased by the heat of summer, or dimi-
nished by the cold of winter, but found sometimes even
to increase on immersion in cold water,* demonstrate
that the action of the minute vessels varies according
to the temperature of the medium in which we are
placed: so that, when exposed to a low temperature
(by which their tone is probably augmented) more oxy-
gen is exchanged for carbon and more heat evolved,
while in a high and debilitating temperature this ex-
change is diminished and less heat evolved.

171. The corium, which covers the body, and the
internal surface of the alimentary canal, eminently con-
tribute, if we are not much mistaken, to regulate our
temperature. For both these organs are supplied with
an immense number of blood-vessels, being analogous in
this respect to the lungs, and are so intimately con-
nected with the lungs by means of sympathy, as in
some degree to perform a part, and occasionally the
whole, of some of their functions in their room. This
is exemplified in adults labouring under nearly total
consumption, or other violent affections, of the lungs,
and nevertheless, existing for a length of time almost
without respiration.§

[Seite 113]

172. This opinion respecting the action of the cuta-
neous
vessels in exciting, moderating, or almost extin-
guishing, our heat, receives much support from the
physiological and pathological facts of some parts being
frequently of a higher or lower temperature than the
rest of the system.

Thus we must attribute the coldness of the dog’s
nose to the specific action of its own vessels being
modified differently from that of the rest; so on the
other hand, the burning sometimes of the cheeks and
sometimes of the palms of the hands in hectic fever, to
the locally increased action of the vessels; besides
other phenomena of the same description, v.c. the
heat of the genitals during the venereal oestrum, and
the obstinate coldness of the feet in certain diseases.

173. The alimentary canal is the only internal part,
besides the lungs, exposed to the contact of the atmos-
phere. There is scarcely occasion to prove that it is
so exposed, and that we swallow a considerable quan-
tity of air.

The air, when swallowed, is decomposed in the sto-
mach and intestines, so that, during health, it soon
loses its elastic form: not, however, when the capil-
laries of the canal are debilitated, nor when it exists
in too great quantity.

The immense congeries of blood-vessels in the intes-
tines on their internal surface which is usually thought
equal to the external surface of the body, agrees very
well with this idea.


NOTE.

[Seite 114]

No phenomenon in living bodies is more remarkable than their
peculiar temperature, and no one was of more difficult explana-
tion before the progress of modern chemistry.

If two different bodies are placed in a temperature higher or
lower than their own for a certain length of time, they will, at
the end of the period, be found not of the same, but of different,
temperatures. That which has the higher temperature, is said
to have a smaller capacity for caloric; that which has the lower,
a greater capacity. To raise the former to a given temperature,
therefore, requires less heat than to raise the latter to the same
degree.

The temperature of solids is more easily affected by a given
quantity of heat, than that of fluids, and the temperature of fluids
than that of aëriform bodies: or, in other words, solids have a
smaller capacity for caloric, than fluids, and fluids than aëriform
bodies. If, therefore, a solid becomes fluid, or a fluid aëri-
form, it absorbs a great quantity of heat, though its temperature
remain precisely the same. And the converse holds equally
good, – if an aëriform substance becomes liquid, or a liquid solid,
the heat which it before contained is now (from its diminished
capacity) much more than sufficient for the temperature which
before existed, and the temperature of the body accordingly rises.

In respiration, the dark blood of the pulmonary artery parts
with a portion of its carbon and acquires a florid hue. This car-
bon unites with the oxygen of the inspired air, and forms carbonic
acid that is expired with the other constituent of the atmos-
phere, – nitrogen or azote, which appears to have experienced
no change from inspiration.

Dr. Crawford rendered it probable, by his experiments, that
the arterial blood has a larger capacity for caloric than the
venous, and common air than carbonic acid gas. When, there-
fore, the carbon of the venous blood unites with the oxygen of
[Seite 115] the air and forms carbonic acid, the smaller capacity of this than
of common air for caloric, must cause an increase of tempera-
ture, but the blood, having changed from venous to arterial, has
acquired a greater capacity than before and absorbs the heat given
out by the carbonic acid. The blood, of course, does not become
warmer, because the heat is not more than sufficient to render
its temperature equal to what it was previously; and indeed
it is not quite sufficient for this, since the arterial blood of the
pulmonary veins is generally two degrees lower than that of the
pulmonary artery.

The body in this way acquires a fund of heat, and yet the
lungs, in which it is acquired, do not experience any elevation
of temperature.

The arterial blood, charged with much heat which is not sen-
sible, as it circulates through the small vessels, becomes venous, –
acquires a dark hue, and its capacity for heat is diminished;
consequently its temperature rises, – the heat which was pre-
viously latent, is, from the decrease of capacity, sufficient to
raise its temperature, and is evolved. In this mode, the loss of
heat which occurs from the inferior temperature in which we
live, is compensated. The fresh supply is taken in at the lungs,
and brought into use in the minute vessels.

Of late, this theory has fallen into discredit.

All experiments upon the capacities of bodies for heat are very
delicate and liable to error; and the conclusions of Crawford on
this point have been denied by M.M. Delaroche and Berard,
with respect to the gases, and by Dr. Davy, with respect to arte-
rial and venous blood.*

Mr. Brodie cut off the communication between the brain and
lungs of animals, and continued respiration artificially. The
usual chemical changes continued in the lungs upon the blood,
nevertheless the temperature of the animals diminished, and even
more rapidly than if the respiration had not been continued, owing,
[Seite 116] he says, to the succession of cool air sent into the lungs. He
therefore concludes, that animal heat depends much more upon
the nervous energy than upon the chemical changes of the
blood. But Le Gallois asserts, that under artificial respiration
the temperature falls, even if every part remain uninjured.*
Dr. Crawford himself states that the chemical process of respi-
ration may, in certain cases, be the means of cooling the body.

If the pulmonary exhalation is in very great abundance, it will
carry off so much of the heat given out during the change of the
oxygen into carbonic acid, that there may not be sufficient to
saturate the increased capacity of the arterial blood; this will
therefore absorb heat from the system, as it passes along, till its
temperature equals that of the other parts.

Many circumstances, however, favour the doctrine of Crawford.
In high temperatures we have less necessity for the evolution of
heat by the chemical changes of the blood and air, whereas, in
low temperatures, as more heat is required to sustain the natural
degree of temperature, the chemical changes are more necessary.
Accordingly, in very high temperatures, the arterial blood
remains arterial, – is as florid in the veins as in the arteries, and
the inspired air is less vitiated; in low temperatures, the venous
blood is extremely dark, and the inspired air more vitiated.

The temperature is also regulated by the degree of perspi-
ration, the momentum of the blood, &c. In proportion as more
vapour transpires from the skin, will more heat be carried off,
whence M. Delaroche heated animals at pleasure like inanimate
matter by saturating their atmosphere with humidity, thus pre-
venting cutaneous and pulmonary evaporation. And as the sum
of the quantity and velocity of blood in any part is greater, the
temperature of that part will be higher. Whether Crawford’s
theory be correct or not, the production of animal temperature
must still be as evidently a chemical process as changes of tem-
perature among inanimate bodies. But this does not prevent it
[Seite 117] from strictly deserving the epithet vital, because it is regulated
by the vital powers of the system, although through the instru-
mentality of chemical changes. If the high temperature of an
inflamed part is owing to the increased momentum of the blood,
yet this increased momentum is produced by the vital powers.
As there is less vigour in old than in young persons, and in
remote parts than in those which are near the centre of circu-
lation, the momentum of the blood is less in the old than the
young, and in parts remote than in parts near the heart; hence
the temperature of the old falls short of the temperature of the
young, and is stated to be in all persons lower in proportion to
the distance of parts from the centre of circulation.*

All animate matter has a tendency to preserve a certain tem-
perature. Even eggs are cooled and frozen with more difficulty
than equal masses of inanimate matter, though, when once frozen
and their life destroyed, they freeze readily. Vegetables shew
the same tendency by the greater difficulty with which the juices
in their stems and branches are frozen than lifeless fluids, and by
ice thawing when roots shoot into it.

SECT. XI.
OF PERSPIRATION.

[Seite 118]

174. The functions of the skin, which affords a cover-
ing to the body, are so extremely various that they
cannot all be easily described with advantage in one
chapter, but each will be considered far more conve-
niently under that class of actions to which it belongs.

For, in the first place, the skin is the organ of touch,
and will be examined in this view, under the head of
animal functions.

It is an organ of inhalation, and in this point of view
belongs to the absorbent system, to be spoken of among
the natural functions.

It is likewise the organ of perspiration, and on this
account related in many ways to the function of respi-
ration, and may, we think, very properly follow it in
this place,

175. The skin consists of three membranes – The co-
rium,
internal; the cuticle, external; and the reticulum,
intermediate.

176. The cuticle or epidermis* forms the external
covering of the body, is separable into lamellae, and
exposed to the atmosphere, the contact of which can
be borne by scarcely any other part, if you except the
[Seite 119] enamel of the teeth. For this reason, the internal cavi-
ties and the canals which communicate with the surface
for the purpose of admitting air, especially the respi-
ratory passages and the whole of the alimentary canal,
the tongue, the inside of the cheeks, the fauces, and the
organ of smell, are covered by a fine epithelium, origi-
nating from the epidermis.*

177. The texture of the epidermis is extremely simple,
destitute of vessels, nerves, and of true mucous web,
and consequently but little organised; very peculiar,
however, remarkably strong, considering its pelluci-
dity and delicacy, so that it resists for a great length of
time maceration, suppuration, and other modes of
[Seite 120] destruction, and reproduced more easily than any other
of the similar parts.

178. It is completely sui generis, somewhat like a
horny lamella, and adheres to the subjacent corium by
the intervention of a mucus, and by numerous very
delicate fibrils which penetrate the latter.*

The pores which Leuwenhoek imagined in it, do not
exist; but it allows a very ready passage to caloric, car-
bon, hydrogen, and to matters immediately composed
of these, v.c. oil.

179. The importance of the cuticle to organised sys-
tems, is demonstrated by its universality in the animal
and vegetable kingdoms, and by its being distinctly ob-
servable in the embryo from the third month at latest
after conception.

180. The inner part of the cuticle is lined by a fine
mucous membrane, denominated from the opinion of its
discoverer, reticulum Malpighianum, and by means of
which chiefly the cuticle is united more firmly to the
corium.

Its nature is mucous, it is very soluble, and, being
thicker in Ethiopians, may be completely separated in
them from both the corium and cuticle, and made to
appear as a true distinct membrane. (B)

[Seite 121]

181. Our colour resides in it. In all persons the
corium is white, and, in almost all, the cuticle white and
semipellucid, though in Ethiopians it inclines to grey.
But the mucous reticulum varies after birth, with age,
mode of life, and especially with difference of climate.

Thus among the four varieties into which I would
divide the human race, in the first, which may be
termed Caucasian and embraces Europeans (except the
Laplanders and the rest of the Finnish race), the western
Asiatics, and the northern Africans, it is more or less
white.

In the second or Mongolian, including the rest of the
Asiatics (except the Malays of the peninsula beyond the
Ganges), the Finnish races of the north of Europe, as
the Laplanders, &c. and the tribes of Eskimaux diffused
over the north of America, it is yellow or resembling
box wood.

In the third – the Ethiopian, to which the remainder
of the Africans* belong, it is of a tawny or jet black.

In the fourth or American, comprehending all the
Americans excepting the Eskimaux, it is almost copper
coloured, – of a dark orange or ferruginous hue.

In the fifth or Malaic, in which I include the inhabi-
tants of all the islands in the Pacific Ocean, and of the
Philippine and Sunda, and those of the peninsula of
Malaya, it is more or less tawny, – between the hue of
fresh mahogany and that of cloves or chesnuts.

[Seite 122]

All these shades of colour, as well as the other cha-
racteristics of nations and individuals, run so insensibly
into one another that all division and classification of
them must be more or less arbitrary.

182. The essential cause of the colour of the Mal-
pighian mucus, is, if we mistake not, the proportion of
carbon which is excreted together with hydrogen from the
corium, and in dark nations, being very copious, is pre-
cipitated upon the mucus and combined with it.*

183. The corium, which is covered by the reticulum
and epidermis, is a membrane, investing the whole body
and defining its surface; tough; very extensible; of dif-
ferent degrees of thickness; every where closely united,
and, as it were, interwoven, with the mucous tela, espe-
cially externally, but more loosely on its internal sur-
face, in which, excepting in certain parts, we generally
discover fat.

184. Besides nerves and absorbents, innumerable
blood vessels, of which we shall speak hereafter, pene-
trate to its external surface, upon which they are shewn,
by minute injection, to form very close and delicate
net-works.

185. A vast number of sebaceous follicles also are
dispersed throughout it, which diffuse over the skin an
oil, thin, limpid, and not easily drying, altogether
[Seite 123] distinct, from the common sweat, and from that which
possesses an odor resembling the odor of goats and
is peculiar to certain parts only.

186. Lastly, almost every part of the corium is beset
with various kinds of hairs,* chiefly short and delicate,
more or less downy, and found nearly every where but
on the palpebrae, penis, the palms of the hand, and the
soles of the feet. In some parts, they are long and des-
tined for peculiar purposes; such are the capilla-
mentum, the eyebrows, the eye-lashes, the vibrissae,
mustachios, beard, and the hair of the arm-pits and
pudenda.

187. Man is, generally speaking, less hairy than most
other mammalia. But in this respect nations differ.
For, not to mention those nations who to this day care-
fully pluck out their beard or the hair of other parts,
others appear naturally destitute of hair, v.c. the
Tunguses and Burats; (C) on the contrary, creditable
travellers assert that some inhabitants of the islands in
the Pacific and Indian Ocean are remarkable hairy.

188. Nor is there less variety in the length, flexibi-
lity, colour, and disposition to curl, both in each race
of men enumerated above (181) and in individuals. V.c.
The hair of the head in the Caucasian variety is rather
dingy or of a nut brown, inclined on one hand to yellow
and on the other to black; in the Mongolian and Ame-
rican, it is black, stiffer, straight, and more sparing; in
the Malay, black, soft, curling, thick, and abundant; in
the Ethiopians, black and woolly: In individuals, espe-
[Seite 124] cially of the Caucasian variety, there are great differ-
ences, and chiefly in connection with temperament, which
is found intimately and invariably connected with the
colour, abundance, disposition to curl, &c. of the hair;*
and there also exists a remarkable correspondence be-
tween the colour of the hair and of the iris.

189. The direction of the hairs is peculiar in certain
parts, v.c. – spiral on the summit of the head – di-
verging upwards on the pubes – on the exterior of the
arm, as is commonly seen in some anthropomorphous
apes, (v.c. in the satyrus and troglodytes) running in
two opposite directions towards the elbow, i.e. down-
wards from the shoulder, upwards from the wrist; to
say nothing of the eye-lashes and eye-brows.

190. The hairs originate from the inner surface of
the corium, which abounds in fat. They adhere to it
pretty firmly, by a curious bulb, consisting of a double
involucrum; – the exterior vascular and oval, the inte-
rior cylindrical, apparently continuous with the epider-
mis,§ and sheathing the elastic filaments of which the
hair is composed, and which are generally from five to
ten in each.

191. The hairs are almost incorruptible, and always
anointed by an oily halitus. Of all parts they appear
[Seite 125] most truly electrical. They are very easily nourished,
and even reproduced, unless where the skin is diseased.

192. Besides the functions ascribed to the integu-
ments in the former Section, must be enumerated their
excretory power, by which foreign and injurious matters
are eliminated from the mass of fluids.*

This is exemplified in the miasmata of exanthematic
diseases, in the smell of the skin after eating garlic,
musk, &c. and in sweating and similar phenomena.

193. What is most worthy our attention, is the tran-
spiration of an aëriform fluid, denominated, after the
very acute philosopher who first applied himself pro-
fessedly to investigate its importance, the perspirabile
Sanctorianum,
and similar to what is expired from the
lungs. It likewise is composed of various proportions
of carbon,§ nitrogen, and hydrogen,ǁ precipitates lime
from solution, and is unfit to support either flame or
respiration.

194. The sweat, which seldom occurs spontaneously
during health and rest, unless in a high temperature,
appears to arise from the perspirable matter of Sanc-
torius being too much increased in quantity by the
excited action of the cutaneous vessels, and from its
[Seite 126] hydrogen uniting with the oxygen of the atmosphere
and assuming the liquid form.

195. Upon the same hydrogen, variously modified by
the accession of other elements and constituents, would
seem to depend the natural and peculiar odour perceived
in the perspiration and sweat of certain nations and in-
dividuals.*

196. The quantity of matter perspired from the inte-
guments which, in a well grown adult, are equal to
15 square feet, cannot be accurately estimated, but is
probably about two pounds in 24 hours. (D)


NOTES.

(A) One of this family has just been exhibiting himself in
Bond Street. He is thirty years of age and states himself to
belong to the fourth generation of the descendants of a savage
who was found in the woods of America and had the same con-
dition of skin. It is transmitted to every male without exception
in the male line, but has never appeared in the females or their
male offspring. The horny warts first show themselves at two
[Seite 127] months from birth, are constantly growing, though most in
summer, and are constantly being shed, but particularly in win-
ter, till the thirty-sixth year, after which they are never shed,
but continue to grow, so that in this man’s father, who is eighty
years of age and lives in Suffolk, they are of very great length.
They are set so close together, that their tops form a tolerable
surface, unless they are separated by extending the skin. Nearest
those parts which are natural, they gradually become smaller.
The glans penis should have been excepted by Blumenbach as
well as the scalp, face, palms, and soles.

(B) Although Dr. Gordon* and Mr. Lawrence assert that they
have never been able to detach any thing from the cutis of Euro-
peans in the form of a distinct membrane, the rete Malpighianum
does exist in Negroes, and the latter gentleman allows that the
various complexions of Europeans and the peculiar cream white
of the Albino who has unquestionably no colouring matter in his
eyes or skin, show that it exists even in us.

(C) The illustrious Dr. Wells describes the singular case of a man
whose hair fell off throughout his body in about six weeks, without
any evident cause or derangement of health. He always looked
afterwards as if just shaved, and by wearing a wig would not
have been noticed for any peculiar appearance.

(D) The functions of the skin are but imperfectly known.
Besides forming a watery secretion (193 sq.)§ and producing
[Seite 128] chemical changes similar to those which occur in the lungs (171),*
it is believed by some to be an organ of absorption, while others
deny that absorption ever takes place unless friction is employed
or the cuticle abraded. Dr. Currie’s patient labouring under
dysphagia seated in the oesophagus, always found his thirst re-
lieved by bathing, but never acquired the least additional weight.
Dr. Gerard’s diabetic patient weighed no more after cold or warm
bathing than previously. Seguin found no mercurial effects
from bathing a person in a mercurial solution, provided the
cuticle remained entire; they occurred, however, when the cuticle
was abraded.§

But the two former cases are no proofs that water was not
absorbed, because the persons immersed did not lose in weight,
which they would have done if not immersed, owing to the
pulmonary excretions; this therefore must have been counter-
balanced by absorption somewhere, and no shadow of proof can
be urged against its occurrence by the skin, as Dr. Kellie re-
marks in his excellent paper on the functions of this part.ǁ
Seguin besides found two grains of the mercurial salt disappear
in an hour from the solution when of the temperature of 18°
Reaumur.

[Seite 129]

There is every reason to believe the occurrence of cutaneous
absorption independently of friction or abrasion of the cuticle.
First, the existence of absorbents all over the surface cannot be
intended for use merely when friction is employed or the cuticle
abraded. Secondly, we have many facts which prove absorption
without these circumstances, either by the skin or lungs or both,
while no reason can be given why they should be attributed
solely to the lungs. A boy at Newmarket who had been greatly
reduced before a race, was found to have gained 30 oz. in weight
during an hour, in which time he had only half a glass of wine.*
Dr. Home, after being fatigued and going to bed supperless,
gained 2 oz. in weight before seven in the morning.* In three
diabetic patients of Dr. Bardsley’s, the amount of the urine ex-
ceeded that of the ingesta, and the body even increased in weight,
and in one of the instances as much as 17 lbs. Dr. Currie
allows that in his patient, ‘“The egesta exceeded the ingesta in
a proportion much greater than the waste of his body will ex-
plain.”’ Similar facts are recorded by De Haen, Haller, &c.
The same patient’s urine too after the daily use of the bath,
flowed more abundantly and became less pungent.

SECT. XII.
OF THE FUNCTIONS OF THE NERVOUS SYSTEM
IN GENERAL.

[Seite 130]

197. We now come to the other class of functions
termed animal (83, II.), by which the body and mind
are connected. They have obtained their name from
existing in animal systems only, and from enjoying a
greater range than those properly denominated vital.

198. The principal organs of these functions are the
brain, medulla spinalis, and the nerves, the greater part
of which originate from the two former.* They may
be properly referred to two classes, sensorial and ner-
vous:
the former comprehending all excepting the nerves
and their immediate origin, – all that serves more di-
rectly as the connection between the office of the nerves
and the faculties of the mind.

199. Upon this division rests the beautiful observa-
tion of the illustrious Sommerring respecting the cor-
respondence between the relative size of each class
with the faculties of the mind. – That the smaller the
nerves are, compared with the sensorial class, the greater
is the developement of the mental faculties. In this
sense, man has the largest brain of all animated beings,
[Seite 131] – if its bulk be compared with that of the nerves arising
from it; but by no means, if its weight be compared
with that of the whole body.

200. Besides the bony cranium, a threefold covering
is afforded to the brain,* viz. the dura and pia mater,
and, between these two, the tunica arachnoidea.

201. The dura mater, which lines the inside of the
cranium, like a periosteum, forms various processes.
By the falx it divides the hemispheres of the cerebrum
and cerebellum; by the tentorium it supports the
posterior lobes of the cerebrum and prevents their
pressure upon the subjacent cerebellum.

In its various duplicatures it contains and supports
the venous sinuses§ and prevents their pressure. These
receive the blood returning from the brain to the heart,
the proportion of which to the rest, Zinn long ago very
truly remarked, has been overrated by physiologists.

[Seite 132]

202. Next to the dura mater lies the arachnoid, so
named from its thinness. Its use is not exactly known;
it is destitute of blood-vessels (5), and extended, like
the dura mater, merely over the substance of the brain,
without following the course of its furrows and promi-
nences.

203. On the contrary, the membrane called pia mater
by the ancients, closely follows the cortical substance
of the brain,* and possesses innumerable blood-vessels
which penetrate into the latter. Hence, if a portion of
this membrane is detached, we find the external surface
very smooth, while the internal is villous and resem-
bles the roots of moss. (A)

204. The cerebrum and cerebellum are composed of
various parts which differ in texture and figure, but
the use of which is unknown. The most remark-
able are the four ventricles, in the two anterior and
fourth of which are found the choroid plexuses, of
whose function also we are ignorant.§

205. The substance of the brain is twofold: the one
called cineritious or cortical, though not always situated
exteriorly; the other white or medullary. Between the
two, Sömmerringǁ has detected a third substance,
most conspicuous in the arbor vitae of the cerebellum
and the posterior lobes of the cerebrum.

[Seite 133]

206. The proportion of the cineritious* to the cor-
tical substance decreases as age advances, being
greater in children, less in adults. It is almost wholly
composed of very fine vessels, both sanguiferous and
colourless (92), of which some few penetrate into the
medullary substance: the latter is composed, in ad-
dition to these vessels and a fine cellular substance, of
a pultaceous parenchyma, which, if examined with
glasses, exhibits no regular structure,§ and, upon che-
mical analysis, affords a peculiar matter, in some mea-
sure resembling albumen. (B)

207. The brain, after birth, undergoes a constant and
gentle motion,ǁ correspondent with respiration; so
that, when the lungs shrink in expiration, the brain
rises a little, but when the chest expands, it again sub-
sides.**

[Seite 134]

208. The spinal marrow is continuous with the brain,*
and may be said either to spring from the brain, as
from a root, or, on the contrary, to terminate in it and
grow into its substance. Contained in the flexible
canal of the vertebrae, it is enveloped by the same
membranes as the brain: its substance is also twofold,
but the medullary is exterior to the cineritious.

209. From these two sources – the brain and spinal
marrow, arises the greater part of those chords, which
are more or less white and soft, chiefly composed of
cellular canals containing nervous medulla, and dis-
tributed throughout nearly all the soft parts: some
nerves,§ however, may be more properly considered as
uniting with the brain and spinal marrow than springing
from them. (C)

[Seite 135]

210. After the numerous experiments* made by
Haller and other very careful observers, we are cer-
tain, from minute anatomical examination, that many
of the similar parts do not exhibit any true vestige of
nerves; and from surgical observation and dissections
of living animals, that they do not evince the least
sign of feeling.

[Seite 136]

Such are the cellular substance, the epidermis and
reticulum mucosum, the hairs and nails.

The cartilages, bones, periosteum, and marrow.

The tendons, aponeuroses, and ligaments.

Most extended internal membranes, as the dura
mater and arachnoid; the pleura, mediastinum, and
pericardium; the peritonaeum; also the cornea, &c.

The greater part of the absorbent system, especially
the thoracic duct.

Lastly, the secundines and umbilical chord. (D)

211. The ultimate origin of most nerves from the
brain cannot be detected. A question is agitated even
at the present day, – whether the nerves of each side
arise from the corresponding or the opposite portion of
the brain.* The latter opinion is countenanced by
certain pathological phenomena, and by the decussa-
tion of fibres in the medulla oblongata and conjunc-
tion of the optic nerves.§ (E)

212. A continuation of the pia mater follows the me-
[Seite 137] dulla of the nerves at their commencement,* in such a
way, as to unite very delicately with the vascular
cortex. But as soon as they have quitted the brain
or medulla spinalis, their structure becomes peculiar,
different from that of all the other similar parts. They
form transverse folds more or less oblique and angular,
long since described by P.P. Mollinelli, who not in-
aptly compared them to the rugae of earth-worms or
the rings of the aspera arteria.

213. The nerves, especially those which are remark-
able, for instance, the intercostals and par vagum, are
here and there furnished with ganglia, or nodules of a
compact structure and reddish ash colour, but with
whose functions we are scarcely acquainted. I am in-
clined to believe with Zinn§ that they more intimately
unite the nervous filaments which meet in them from
various directions, so that each fibre passing out
is composed of a portion of every fibre that has en-
tered in.ǁ

Nearly the same holds good with respect to the plex-
[Seite 138] uses, which are produced by the union and reticulated
anastomoses of different nerves and by a similar con-
texture of filaments into which the nerves are split.

214. The ganglia and plexuses are most abundantly
bestowed upon the spinal nerves and the intercostal
or sympathetic nerve. The latter, united by a few deli-
cate filaments only with the rest of the nervous system,
constitutes a peculiar system, chiefly belonging to the
involuntary functions. For this reason, Bichât, view-
ing it as presiding over organic life, distinguished it
from the other nerves belonging to animal life, to use
his own language.*

215. The terminations of the nerves are no less con-
cealed from us than their origins. Excepting a few
which spread out in the form of membranes, as the
optic nerve which becomes the retina, and the portio
mollis of the seventh pair which forms a zone in the
spiral lamina of the cochlea, the ultimate filaments of
the rest penetrating into the viscera, muscles, corium,
&c. are so intimately blended with the substance of
these parts as to elude observation.

216. The parts just described, viz. the sensorium and
the nerves originating in it and distributed throughout
the body, constitute that system which, during life, is
the bond of union between the body and the mind.

217. That the mind is closely connected with the
brain, as the material condition of mental phenomena,
is demonstrated, to omit such arguments as the imme-
diate connection between the brain and the organs of
sense, by our consciousness and by the mental disturb-
ances which ensue upon affections of the brain. (F)

[Seite 139]

218. The singular situation and form, before alluded
to, of certain parts of the brain, and likewise some
pathological phenomena, have induced physiologists
to suppose certain parts, in particular, the seat of the
soul. Some have fixed upon the pineal gland,* others
the corpus callosum, the pons Varolii, the medulla
oblongata, the corpora striata, and the water of the
ventricles, which washes against the origin of some
nerves. Others not contented with one spot, have
assigned particular parts of the brain for individual
faculties and propensities. (G)

219. The energy of the whole nervous system does
not depend solely upon the brain. The spinal marrow,
and even the nerves, are possessed of their own powers,
which are sufficient to produce contractions in the
muscles. These powers are probably supported by
the vascular cortex of those parts (212). In man, the
powers proper to the nerves are less, and those depend-
ent upon the brain greater, than in brutes, especially
the cold-blooded.

220. The office of the whole nervous system is two-
fold, – To excite motion in other parts, especially in the
voluntary muscles, of which we shall hereafter speak at
large; and to convey impressions made upon the
organs of sense to the brain, and there to excite per-
[Seite 140] ception or by means of sympathies (56) to give occasion
to reaction.

221. Experiment and observation put these functions
of the nervous system beyond the reach of controversy.
To unfold their nature is difficult indeed. (H)

222. Most opinions on this subject may be divided
into two classes. The one regards the action of the
nervous system as consisting in an oscillatory motion:
The other ascribes it to the motion of a certain fluid,
whose nature is a matter of dispute, by some called
animal spirits* and supposed to run in vessels, by
others conceived to be a matter analogous to fire, to
light, to a peculiar ether, to oxygen, to electricity, or
to magnetism.

223. Although I would by no means assent to either
of these opinions, I may be allowed to observe, that most
arguments brought by one party against the hypothesis
of the other, must necessarily be rude in proportion to
the subtlety of the oscillations (if such exist) of the
nerves or the nervous fluid.

224. These two hypotheses may, perhaps, be united
by supposing a nervous fluid thrown into oscillatory
vibrations by the action of stimulants.

225. The analogy between the structure of the brain
and some secreting organs, favours the belief of the
existence of a nervous fluid. But tubes and canals are
evidently no more requisite for its conveyance, than
they are requisite in bibulous paper or any other matter
employed for filtering.

The opinion receives much weight from the resem-
[Seite 141] blance of the action of the nerves to the phenomena pro-
duced by the series of a galvanic apparatus and by the
common electrical machine,* in a living animal or in
parts not quite deprived of vitality. These phenomena
in fact long ago induced some physiologists to compare
the nervous to the electric fluid. The singular and
undeniable effects attributed to animal magnetism, as
well as other phenomena which have given rise to the
belief of a kind of sentient atmosphere surrounding
the nerves, agree very well with the same hypothesis.

226. If we regard the oscillation of the nerves, not
as similar to that which occurs in tense chords, but of
such a description as may be conceived to occur in
the soft pulp of the brain, we shall find many phy-
siological phenomena exactly corresponding with the
supposition.

It is demonstrated that hearing depends upon an
oscillation.

In vision also it probably occurs, although not to
the extent imagined by Euler.

The penetration of Hartley§ in following up the
conjectures of the Great Newton,ǁ has rendered it so
probable that the action of the other senses is not very
[Seite 142] dissimilar from this oscillatory motion, that on the
same supposition he very ingeniously explains, prin-
cipally by means of the vapour of the ventricles (called
by him the denser ether),* first, the association of ideas,
and again, by the assistance of this, most of the func-
tions of the animal faculties. (I)


NOTES.

(A) The Pia Mater and Tunica Arachnoides were considered
as the same, till the Anatomical Society of Amsterdam con-
firmed, in 1665, the doubts which were arising on the subject
and Van Horne demonstrated both membranes distinctly to his
pupils. The Dura Mater corresponds with the fibrous mem-
branes, the Pia Mater with the cellular, and the Tunica Arach-
noides
with the serous. The latter is, in nature, office, and dis-
eases, exactly like the serous; – a close sac, affording, as the
peritonaeum does to the abdominal viscera, a double covering to
the brain and spinal marrow and the nerves before their departure
through the foramina of the Dura Mater, and lining the ven-
tricles; insulating the organs on which it lies, and affording
them great facility of movement; and liable to all the morbid
affections of serous membranes.

(B) Fibres are very evident in the cerebral substance. Mr. Bauer
has discovered globules, but then he finds fibres to be series of
globules.

[Seite 143]

(C) Drs. Gall and Spurzheim have shewn that the nerves and
spinal marrow do not arise from the brain, but only communicate
with it: for, when the brain is absent, the foetus equally possesses
them, and neither the cerebral nerves nor the spinal marrow are
in proportion to each other in the various species of the animal
kingdom, nor the spinal nerves to the spinal marrow.

(D) Although no nerves can be discovered in these parts, and
although ordinarily they have no feeling, yet that they have, in
a lower degree, what, in a higher is called feeling, is shewn by
the extreme sensibility which they acquire when inflamed, as they
nearly all frequently are.

(E) Drs. Gall and Spurzheim have also shewn that, besides the
numerous communications of the whole nervous system, not only
the two sides of the cerebrum, cerebellum, and spinal marrow, are
united by commissures, but that the fibres of the anterior pyra-
midal eminences decussate each other, forming an exception to the
rule, observed in every other part of the brain, of the nervous fibres,
destined to each side of the body, running on the same side of the
brain; and they hence explain why injuries of one side of the brain
sometimes influence the same, sometimes the opposite, side of
the body. It is to be hoped that morbid dissection will ascertain.
the correctness of this explanation.

I refer to the writings of these physicians for an account of their
great discoveries in the structure of the nervous system, and shall
merely bear testimony to the truth of most of their anatomical
assertions. Those few which I have not repeatedly seen proved,
are I doubt not perfectly accurate. The most candid anatomical
lecturers of London confess that they knew nothing of the anatomy
of the brain till they saw it dissected by Dr. Spurzheim, and it is
a matter of wonder that while pupils are not instructed to dissect
limbs by slices as we cut brawn, they should be taught no other
mode of examining the brain and thus be left in ignorance of its
true structure.*

[Seite 144]

(F) See Sect. vi. Note A, near the end; and Sect. xliv. Note
E, near the beginning.

(G) Dr. Gall has the immortal honor of having discovered the
particular parts of the brain which are the seat of the different
faculties, sentiments, and propensities.

If it is clear that the brain is the organ of mind, it is extremely
probable that particular portions of it have different offices.

Numerous old writers had assigned situations for the faculties,
but in the most fanciful manner; and from regarding as distinct
faculties what are merely modes of action of faculties to which
they were altogether strangers, their assertions on the subject
were necessarily groundless and ridiculous. Burton, for example,
says of common sense, ‘“the fore-part of the brain is his organ
or seat;”’ of imagination, ‘“his organ is the middle cell of the
brain”’ and of memory, ‘“his seat and organ, the back part of
the brain.”’*

If the old course, recommended by Mr. Dugald Stewart, of
investigating the mind by attending to the subjects of our own
consciousness, had been persevered in, the science of mind would
have remained stationary for ever. Who can judge fairly of
[Seite 145] his own character and talents? Not only is the heart of man
deceitful above measure, but we give ourselves credit for talents
which others know to be insignificant. Our powers too and
dispositions are distributed in such various degrees, that from
this single circumstance, every man, judging from himself only,
would draw up a different account of the human mind. It is
only by extensive observation of others, of different sexes, ages,
education, occupations, and habits, that this knowledge is to
be acquired. Nor would much progress have been made without
the discovery – that strength of individual talent and disposition
was associated with proportionate developement of particular
portions of the brain. By this remark the existence of particular
faculties and inclinations was firmly established. I made no
allusion to craniology while detailing Dr. Spurzheim’s account of
the mind (Sect. V.), because the arrangement may be perfectly
accurate, although craniology be false; nor when speaking of the
brain as the organ of the mind (Sect. VI.), because that fact also
is independent of the system. But if now the account of the
mind, the use of the brain, and craniology, be viewed together,
they will all be seen mutually and beautifully to confirm each
other.

Much disgraceful invective, but no argument, has been written
against the doctrine. We are presented with a simple statement
– that strength of certain parts of the mind, is accompanied by
strong developement of certain parts of the brain, and, conse-
[Seite 146] quently, of the skull. The truth must be ascertained, not by fancy-
ing, quibbling, and abusing, but by observing whether this is the
case: and every one has it in his power to make the necessary ob-
servations. I had heard of a religious bump, a thievish bump,
and a murderous bump, and was as lavish of my ridicule and con-
tempt of Dr. Gall’s doctrine as any one, till I heard Dr. Spurzheim’s
lectures in the Medico-Chirurgical Society. His modesty, can-
dour, and sound sense, struck me powerfully; his anatomical facts
were demonstrated; his metaphysics were simple and natural;
and the truth of his craniology was evidently to be ascertained
by personal observation only. I commenced observations, and
so satisfied was I of its correctness, that whilst the storm was
raging violently against the German physicians, I wrote an ano-
nymous defence of them in the only review that declared itself
their friend. Three years have now elapsed, and my obser-
vations have been much extended, but they all confirm Dr. Spurz-
heim’s statements. Of the accuracy of his general division of
the organs, and of the situation of many particular ones, I am
quite certain. Upon some organs I have not yet made sufficient
observations, and I have no doubt that our views of the func-
tions of many organs will be much modified and improved. It
would be absurd to think the system perfect at present. The
wonder is that so much has been already done, and that by only
two individuals. The whole praise of discovery belongs to
Dr. Gall, but Dr. Spurzheim has made such advances and im-
provements as to have almost equal merit. The science of
craniology is entirely theirs; nearly so henceforward will me-
taphysics be regarded; and anatomy must acknowledge them
among its greatest benefactors. Those who wish to become
acquainted with craniology I must refer to Dr. Spurzheim’s well
known English work,* and to a very clear, forcible, and tempe-
rate publication, by Mr. Coombe, a surgeon in Edinburgh. – Who-
[Seite 147] ever acquires sufficient knowledge of the subject to make obser-
vations for himself, will soon find the shape of the skull to be as
various as character and countenance, and will have hourly
amusement not only in remarking the relation between mental
character and cranial form, but in tracing the resemblance of
children in the latter respect to their parents, as well as in talent
and disposition. I find nothing more interesting than to note
the increase of particular portions of the skulls of children as
their minds become developed. It has been asserted that, after
a certain age, (though this has been very differently fixed) the
brain makes no farther increase in weight; but I know that
various parts of the brain are variously evolved from infancy to
manhood, and that, if children of different ages and young per-
sons are placed side by side, the greater magnitude of the forehead
in the older is strikingly conspicuous.

Should any one doubt his acquaintance with the real talents
and characters of those friends whose heads he can select for
observation, he has only to study the heads of some celebrated
men now living, of whose talents and disposition no one can
have the slightest doubt, and he will find the illustration asto-
nishing.

If these are facts, all objections on the score of fatalism, &c.
however correct, are unworthy of attention. But in truth, cra-
niology gives no additional support to such views. A stone is
destined not to feel; a fish is destined to swim, and a vulture to
be a bird of prey; man is destined to be

‘“Not prone and brute as other creatures, but endued’
‘With sanctity of reason, and to erect’
‘His stature, and upright with front serene,’
‘Govern the rest, self-knowing.”’

The very expression ‘“human nature”’ implies certain innate
faculties and dispositions, generally; the circumstance of pecu-
liar degrees of disposition and talents being hereditary and of
each age having its distinctive character, are quite as favourable
as craniology to the belief of fatalism. Each has his own talents
[Seite 148] and disposition; in some way or other they must be obtained,
and if the way is discovered, the case does but remain the same
as before.* But whatever may be our innate propensities and
powers, we know how much various circumstances influence the
developement of faculties and the strength of dispositions, and
we know that we are free agents: we can move our right hand
or our left, and sit still or walk, exactly as we chuse, and we
possess conscience to guide our conduct.

‘“Reason in man obscured or not obeyed,’
‘Immediately inordinate desires’
‘And upstart passions catch the government’
‘From reason: and to servitude reduce’
‘Man, till then free.”’

Those who have so little soul as always to ask what is the
good of any discovery in nature, may be told that craniology is
calculated to assist parents in the choice of occupations for their
children. And it may be of much service in confirming some
moral views which good sense indeed ought previously to have
suggested. Humility and benevolence are two leading duties.
If we detect the signs of mental deficiency and vice in our own
heads, we may learn to think humbly of ourselves; and if we
detect the signs of great talents and virtues in the heads of
others, we may love them the more as superior and highly fa-
voured beings: whereas if we detect the signs of great virtues
and talents in our heads, we may learn to take no praise to our-
selves, but be thankful for the gift; and if we detect the signs
of intellectual deficiency and vice in others, we may learn to pity
rather than to censure. We may learn not to judge others, nor
even our own-selves, but to leave judgment to Him who only
knows what natural strength of evil inclination, what weakness of
[Seite 149] good, and what unhappy external circumstances, each has had to
contend with. Not revenge, but example, is the professed object
of our legal punishments: – example to the culprit himself and
others, or, if the punishment is capital, to others only; and there-
fore frauds, which, from being very easily committed, may become
very detrimental to society, are punished more severely than those
which, caeteris paribus, from being difficult of perpetration, can
scarcely from their frequency become dangerous. Were moral
demerit regarded, the fraud easily committed, would, ceteris pa-
ribus, be punished the most lightly. A vicious man must some-
times be destroyed, as a wild beast,* for the good of others,
though, for aught we know, his faults may, like the acts of the
beast of prey, be chargeable rather on his nature; and while we
feel justified in punishing, and the culprit is perhaps conscious
how richly he deserves his fate, we may pity in our hearts and ac-
knowledge that we ourselves have often been less excusable.

‘“Teach me to love and to forgive,’
‘Exact my own defects to scan,’
‘What others are to feel, and own myself a man.”’

(H) While the brain is evidently the organ of mind, the nerves
united with it, and the spinal marrow, together with its nerves,
are as evidently the instruments by which it affects, and is affected
by, the other parts of the body, to which these nerves are dis-
tributed. By their instrumentality, the brain contracts the volun-
tary muscles, influences the functions of every other part when
under the operation of the different passions, and receives impres-
sions made upon every other part. The consequences of divisions
of the nerves or spinal marrow, fully substantiate these points.

In brainless foetuses, the circulation, secretion, &c. proceed
equally as in others which, besides spinal marrow, nerves, and
[Seite 150] ganglia, possess a brain. Vegetables absorb, assimilate, circu-
late, secrete, and in many instances contract on the application
of stimuli, and yet are not known to possess nerves. Muscles,
after the division of the nerves which connect them with the
brain, contract equally as before, when irritated. In animals
liable to torpor, the season of torpidity produces its effects equally
upon those muscles whose nerves have been divided, or when
the brain, &c. is destroyed.

After the removal or destruction of the brain and spinal mar-
row in animals, the heart still continues to act and the blood to
circulate, provided respiration is artificially supported.* But the
involuntary functions are closely connected with the brain and
spinal marrow, for the sudden destruction of these parts or a
certain portion of them, puts a stop to the circulation; the
application of stimuli to them excites the action of the heart and,
even after its removal, of the capillaries; to say nothing of the
influence of the passions upon them. Nay more, the involun-
tary functions seem as dependent upon the brain and spinal mar-
row as they probably are upon the ganglia and gangliac nerves,
for the division of the par vagum, or the destruction of that part
of the brain with which it is connected, heavily impairs the func-
tions of the lungs and of the stomach;§ and although the divi-
sion of the spinal marrow, or its nerves, prevents voluntary
power over the corresponding muscles, without suspending the
circulation, &c. in them, yet this, and what are dependent upon
it, – nutrition and animal heat, are evidently impaired, and more, I
think, than can be accounted for by the mere deficiency of mus-
cular action.

[Seite 151]

Much progress, surprisingly much, has been made of late in
our knowledge of the functions of the nervous system, but great
obscurity still hangs over the subject.

(I) These oscillations are purely hypothetical and indeed im-
probable. Were their existence proved, we should know nothing
more of the real nature of the cerebral functions, for we should
have to learn what were the peculiar properties of the nervous
system, which enabled it alone of all substances to produce, when
oscillating, the phenomena which it exhibits. We might as well
attempt to explain the phenomena of motion or of chemical
affinity and galvanism, by vitality and mind, as the phenomena
of vitality and mind by mechanics or chemical affinity and gal-
vanism. They are altogether distinct principles, although there
can be no question that the laws of mechanics and chemical
affinity and galvanism, are important and indispensable in every
living system, in subservience to life and mind. The mind, for
aught we know, may stimulate the voluntary muscles by means
of galvanism communicated along the nerves, but then the gal-
vanism is not mind, it is merely an instrument employed by
the mind.*

SECT. XIII.
OF THE EXTERNAL SENSES IN GENERAL, AND OF
TOUCH IN PARTICULAR.

[Seite 152]

227. One office of the nerves we found to consist in
communicating to the sensorium the impressions made
by external objects. This is accomplished by the exter-
nal senses, which are, as it were, the watchmen of the
body and the informers of the mind.

The latter alone belong to our present subject. For
to regard, with Gorter, the stimulus which inclines us
to relieve the intestines, the sensation of hunger, and
other internal calls of nature, as so many distinct
senses, is unnecessary minuteness, as Haller long since
observed.*

228. Touch merits our first attention, because it is
the first to manifest itself, its organ is most extensively
spread over the whole surface, and it is affected by
most properties of external objects.

229. For we perceive not only some qualities, as
heat, hardness, weight, &c. by the touch only, but our
knowledge obtained by other senses respecting some
qualities is rendered more accurate by the touch; such
qualities are figure, distance, &c.

230. It is less fallacious than the rest of the senses,
and by culture capable of such perfection as to supply
the defects of others, particularly of vision.

[Seite 153]

231. The skin, whose structure we formerly examined,
is the general organ of touch.* The immediate seat is
the papillae of the corium, of various forms in diffe-
rent parts, commonly resembling warts, in some places
fungous, in others filamentous.§ The extremities of
all the cutaneous nerves terminate in these under the
form of pulpy penicilli.

232. The hands are the principal seat of touch pro-
perly so called and regarded as the sense which ex-
amines solidity. The skin of the hands has many
peculiarities. In the palms and on each side of the
joints of the fingers, it is furrowed and free from hairs,
to facilitate the closing of the hand. The extremities
of both fingers and toes are furrowed internally by very
beautiful lines more or less spiral;ǁ and are shielded
externally by nails.

233. These scutiform nails** are bestowed upon man
only and a few other genera of mammalia (we allude to
the quadrumana which excel in the sense of touch),††
[Seite 154] for the purpose of resisting pressure, and thus assisting
the action of the fingers, while examining objects.

They are of a horny nature, but on the whole very
similar to the epidermis. For under them lies the reti-
culum, which in negroes is black;* and under this is
found the corium, adhering firmly to the periosteum of
the last phalanx. These constituent parts of the nails
are striated lengthwise. The posterior edge, which, in
the hands, is remarkable for a little lunated appear-
ance, is fixed in a furrow of the skin; and the nails
are growing constantly from this, so as to be perfectly
renewed about every six months.

SECT. XIV.
OF TASTE.

[Seite 155]

234. We perceive tastes by the tongue and in some
degree by the other neighbouring internal cutaneous
parts of the mouth, especially by the soft palate, the
fauces, the interior of the cheeks, and lips; by them,
however, we taste only what is acrid and very bitter.*

235. The chief organ of taste is the tongue, agile,
obsequious, changeable in form, and, in its remarkably
fleshy nature, not unlike the heart.

236. Its integuments resemble the skin. They are an
epithelium, performing the office of cuticle; the reti-
culum Malpighianum; and a papillary membrane,
but little different from the corium.

237. The integuments of the tongue differ from the
skin chiefly in these respects – in the epithelium being
moistened, not by the oily fluid of the skin, but
by a mucus which proceeds from the foramen caecum
of Meibomius§ and the rest of the glandular expan-
[Seite 156] sion of Morgagni* – and, secondly, in the conformation
of the papillae, which are commonly divided into petio-
lated, obtuse, and conical. The first are very few
in number and situated in a lunated series at the root
of the tongue; the others, of various magnitudes, lie
promiscuously upon the back of the tongue, and chiefly
upon its edges and apex, where taste is most acute.

238. These papillae are furnished with extreme fila-
ments of the lingual branch of the fifth pair;§ and
through them we probably acquire the power of tasting.

The ninth pair,ǁ and the branch of the eighth which
also supplies the tongue,** appear intended rather for
the various movements of this organ, in manducation,
deglutition, speaking, &c.

239. For the tongue to taste properly, it must be
moist, and the substance to be tasted must be liquid,
holding salts in solution.†† (A) For if either is in a
dry state, we may perceive the presence of the sub-
stances by the common sense of touch, which the tongue
possesses in great acuteness, but cannot discover their
sapid qualities. When the tongue tastes very acutely,
the papillae around its apex and margins are in some
degree erected.

NOTE.

[Seite 157]

(A) Certainly an infinite number of bodies are sapid, which
contain no kind of salt.

Some gases and metals are sapid; they however may possibly
be united with the fluids of the mouth, before they produce an
impression: but it is by no means proved that the moisture indis-
pensable for taste is requisite to dissolve the substance tasted and
not to fit the papillae for their office.

SECT. XV.
OF SMELL.

[Seite 158]

240. While taste and smell are closely related by
the proximity of their organs, they are not less so by
the analogy of their stimuli and by some other circum-
stances. For this reason, they have been generally
named chemical or subjective senses.

By smell we perceive odorous effluvia received by
inspiration and applied principally to that part of the
Schneiderian* membrane which invests both sides of
the septum narium and the convexities of the turbinated
bones.

241. Although the same mucous membrane lines the
nostrils and their sinuses, its nature appears diffe-
rent in different parts.

Near the external openings it is more similar to the
skin, and beset with sebaceous follicles from which
arise hairs known by the name of vibrissae.

[Seite 159]

On the septum and the turbinated bones it is fungous
and abounds in mucous cryptae.

In the frontal, sphenoidal, ethmoidal, and maxillary
sinuses, it is extremely delicate, and supplied with
an infinite number of blood-vessels which exhale an
aqueous dew.

242. It appears the principal, not to say the sole, use
of the sinuses,* to supply this watery fluid, which is
perhaps first conveyed to the three meatus of the nos-
trils and afterwards to the other parts of the organ,
preserving them in that constant state of moisture which
is indispensable to the perfection of smell.

The sinuses are so placed, that, in every position of
the head, moisture can pass from one or other of them
into the organ of smell.

243. The principal seat of smell, – the fungous por-
tion of the nasal membrane, besides numerous blood-
vessels, remarkable for being more liable to sponta-
neous hemorrhage than any others in the body, is sup-
plied by nerves, chiefly the first pair, which are dis-
tributed on both sides of the septum narium, and also
by two branches of the fifth pair. The former appear
to be the seat of smell: the latter to serve for the com-
mon feeling of the part, which excites sneezing, &c.

[Seite 160]

244. The extreme filaments of the first pair do not
terminate in papillae, like the nerves of touch and taste,
but, as it were, deliquesce into the spongy and regular
parenchyma of the nasal membrane.

245. The organ of smell is very imperfect and small
at birth. The sinuses scarcely exist. Smell conse-
quently takes place but late – as the internal nostrils
are gradually evolved, and is more acute in proportion
to their size and perfection.*

246. No external sense is so intimately connected
[Seite 161] with the sensorium and internal senses, nor possesses
such influence over them, as the sense of smell.*

No other is so liable to idiosyncrasies, nor so power-
ful in exciting and removing syncope.

Nor is any other capable of receiving more de-
licate and delightful impressions; for which reason,
Rousseau very aptly called smell, the sense of imagi-
nation.

No sensations can be remembered in so lively a
manner as those which are recalled by peculiar odors.


NOTE.

An odor must, to be smelt, pass through the nostrils with a
stream of air: – a large bottle of ammonia may be kept under
the nose for any length of time without affecting it, although
the ammonia is all the time flying off.§ Odorous substances
placed in the mouth and a very foetid secretion in the nose or
mouth are perceived only when the air is moving through the
nostrils and give a stronger impression the more forcibly the air
is impelled.

External odors are smelt only when the air passes through
the nostrils from without: – after smelling a substance in the
usual manner, we in vain attempt to catch the odor a second
time by returning the stream of air out again through the nostrils.

[Seite 162]

Many substances excite both smell and taste, – a compound
sensation to which Dr. Prout, in a very original paper,* conceives
the term flavour properly to apply: hence, in catarrh, such
substances scarcely give any sensation, as the sense of smell, –
one ingredient, is impaired.

SECT. XVI.
OF HEARING.

[Seite 163]

247. Sound, which is excited by the collision of
elastic bodies and propagated by the air, is perceived
by the sense of hearing,* and is first received by the
conchiform cartilaginous external ear, which few of
our countrymen have the power of moving. By this
it is collected; then conveyed into the meatus audi-
torius, which is anointed by a bitter cerumen;§ (A)
and strikes against the membrana tympani, which is
placed obliquely in a circular furrow of the temporal
bone and separates the meatus from the internal ear.

248. Behind this membrane lies the middle portion
of the ear, – the cavity of the tympanum, whose fundus
is directed upwards and inwards.

It contains threeǁ ossicula auditus: of which the
exterior, or malleus, adheres by its manubrium to the
membrana tympani, is generally united in the adult
[Seite 164] to the circular furrow above mentioned by its spinous
process which is directed forwards, and it lodges its
round head in the body of the incus.

The incus is united to the head of the stapes by the
extremity of its long process which extends into the
cavity of the tympanum.

The stapes, resting its base upon the fenestra ovalis,
runs towards the vestibule of the labyrinth, into which,
sounds, struck against the membrana tympani, are
propagated by the intervention of these three little
bones.

249. The Eustachian tube* runs from the interior of
the fauces into the cavity of the tympanum: and the
inferior scala of the cochlea has the same direction;
the opening of the latter, termed fenestra rotunda, is
closed by a peculiar membrane. The true and prin-
cipal use of each is not sufficiently known.

250. In the deepest part of the petrous bone is placed
the internal ear, consisting of three parts.

First, of the vestibule, placed between the other two,
into which open not only the fenestra ovalis, but the
five orifices of the semicircular canals which lie pos-
teriorly, and the superior scala of the cochlea which is
placed anteriorly.

The vestibule and semicircular canals loosely con-
[Seite 165] tain very delicate membranous bags, lately discovered
by the celebrated Scarpa. Two of these lie in the
vestibule, and three in the semicircular canals.*

251. They, as well as the cavity of the cochlea, con-
tain a very limpid fluid, bearing the name of Cotunni,
who shewed it to be absorbed by two canals, by him
denominated aqueducts and by the no less illustrious
Meckel diverticula; the one arises from the vestibule,
the other from the inferior scala of the cochlea.

252. The portio mollis of the seventh pair, together
with the portio dura (which afterwards runs along the
Fallopian aqueduct),§ having entered the internal
acoustic opening, transmits its medullary filaments
into the lower and cribriform part of it.ǁ These fila-
ments run to the vestibule and semicircular canals, but
especially to the base of the cochlea, where they form
a medullary zonula, marked by beautiful plexiform
striae, which pass between the two laminae of the sep-
tum cochleae.**

253. The oscillatory tremor, which we formerly fol-
lowed as far as the fenestra ovalis (248), is propagated
to the vestibule, where, by means of the water of
Cotunni (251), it strikes the auditory nerves distributed
among the windings of the labyrinth.

[Seite 166]

254. Besides the muscles of the malleus and
stapes,* supposed to be voluntary, the chorda tym-
pani, which is placed between the handle of the malleus
and the longer leg of the incus, is believed to moderate
the force of sound that is struck against the membrana
tympani and intended to be propagated along the cavity
of the tympanum.§ (B)


NOTES.

(A) The cerumen consists, according to Vauquelin, of al-
bumen, which, when burnt, yields soda and phosphate of lime,
a colouring matter, and a very bitter inspissated oil strongly
resembling the peculiar matter of bile. Cicero, that prodigy of
genius, knowledge, and goodness, explains one use of the
cerumen: – ‘“Provisum etiam, ut, si qua minima bestiola cona-
retur irrumpere, in sordibus aurium, tanquam in visco, inhaeres-
ceret.”’ǁ The same applies to particles of dust. Its extreme
bitterness too deters insects from advancing. Its chief purpose
is probably to preserve the passage in a fit state for conveying
vibrations: – a flute is useless if perfectly dry.

(B) There was an old opinion which appears to my mind
[Seite 167] perfectly correct, – that the membrana tympani is the principal
instrument of distinct hearing; – that its muscles give it various
degrees of tension, putting it in unison with the sounds to which
we are desirous of attending.* I am conscious that some adjust-
ment within the ear takes place when I direct my attention from
one sound to another; some adjustment is demonstrably neces-
sary; the membrana tympani is fitted for this adjustment by its
structure and by a supply of muscles; and when it is scaly and
rigid, every sound may be heard, but without distinctness.

SECT. XVII.
OF SIGHT.

[Seite 168]

255. The instruments of vision, – the eyes,* are two
moveable globes, fixed to the optic nerves whose de-
cussation we formerly noticed (211), as it were to stalks,
in such a manner, that their insertion is not exactly
opposite the centre of the cornea and iris, but behind
this imaginary axis, – rather nearer to the nose.

256. They consist of various coats containing pellu-
cid humours of different degrees of density, so placed
that the rays of light can pass from the transparent
anterior segment of the bulb to the opposite part of
the fundus.

257. The external coat is called sclerotic. It is de-
ficient in the centre, and that part is filled up by the
cornea, which is transparent, lamellated, more or less
convex, and projects like the segment of a small globe
from one of larger size.

258. The interior of the sclerotica is lined by the
chorioid, which abounds in blood-vessels, especially
vorticose veins, and is died on each side by a black
[Seite 169] pigment, adhering, however, but loosely to its concave
surface in the form of mucus.*

259. The chorioid contains the internal coat – the
retina, – a medullary expansion of the optic nerve
which passes through the sclerotica and chorioid, of
most beautiful texture,§ and perforated, in the imagi-
nary axis of the eye, between the two principal branches
of the central artery,ǁ by the singular foramen of
Sömmerring,** which is surrounded by a yellow
edge.†† (A)

[Seite 170]

260. The anterior edge of the chorioid is terminated
by a cellular belt, called orbiculus ciliaris, by which it
adheres firmly to a corresponding groove in the scle-
rotic, and from which two other membranes, viz. the
iris and ciliary processes, are expanded in a circular
form.

261. The iris, (whose posterior surface is lined by a
brown pigment and termed uvea) lies anteriorly to the
ciliary processes, is flat, and washed on all sides by
the aqueous humour; narrower towards the nose,
broader towards the temples. Its texture is dense and
cellular and contains no vestige of muscular fibre.
We must regard it, with Zinn,* as a membrane sui
generis, and not as a propagation from the chorioid.
The anterior surface is differently coloured in different
persons, and, during life, counterfeits a flocculent ap-
pearance.

262. The blood-vessels of the iris run chiefly on its
anterior surface, and are continued in the foetus into
the membrana pupillaris, which begins to open in the
centre at the seventh or eighth month of pregnancy, –
when the eyes have acquired some degree of size, and
when, probably, the elliptic arches of its vessels begin
to be gradually retracted into the inner ring of the iris,
which ring I have never been able to perceive distinctly
before that period.

[Seite 171]

263. The other circular membrane (260) bears the
name of ligamentum or corpus ciliare; and, inclining
backwards, lies at a distance from the iris. Its external
edge is thick* and adheres to the ciliary circle (260):
the internal is thin and adherent to the margin of the
capsule of the lens. The brown pigment is copiously
diffused over it.

Its anterior surface, lying opposite to the uvea, is
striated. The posterior, lying upon the vitreous hu-
mour, is beautifully separated into about 70 flocculi,
remarkable for an indescribably minute and elegant set
of blood-vessels. These flocculi are named ciliary pro-
cesses
and their use is still an object of enquiry.

264. In the bulb of the eye, whose coats we have
now described, are contained the humours, of three
principal kinds.

The posterior, and by far the greater, part of the
globe is filled by the vitreous humour, proportionally
larger in the human subject, especially after puberty,
than in other animals, and so dispersed in innumerable
drops throughout the cells of the delicate hyaloid mem-
brane
that this membranaceo-lymphatic body has the
singular appearance of a tremulous jelly.

265. Anteriorly it adheres to, and by means of the
zona ciliaris surrounds, the capsule containing the crys-
talline lens,
immediately around which lies the water
of Morgagni.

[Seite 172]

The lens itself is very pellucid and cellular, but so
much more dense than the vitreous humour that in the
hand it seems like a very tenacious, although an amaz-
ingly clear, gluten. Its nucleus is more dense than
the exterior lamellae. These may, by management, be
reduced into extremely delicate fibres, converging from
the circumference to the centre.*

In an adult man the lens is proportionally smaller
than in quadruped mammalia; also less convex, espe-
cially on its posterior surface.

266. The remaining space of the eye is filled by the
aqueous humour, which is very limpid, and divided by
the iris into two chambers: – the anterior and larger sepa-
rating the cornea and iris; and the posterior, in which
the uvea lies towards the corpus ciliare, so small, as
scarcely believed by some to exist.

267. These most valuable parts are defended from
injuries both by the depth of their situation in the orbits
and by the valvular coverings of the eye-lids.

In the duplicature of the palpebrae, lie the sebaceous
follicles
of Meibomius, thickly distributed; and their
edges are fringed by a triple or quadruple series of
cilia: the cartilaginous tarsi serve for their support
and expansion, and also facilitate their motion upon
the eye-ball.

Above the eye-lids, to use the language of Cicero,
the skin is covered by the supercilia, which preserve
the eyes from the sweat that flows from the head and
[Seite 173] forehead, and in some measure screen them from too
strong a light.

268. To lubricate the eyes, to preserve their bright-
ness, and to wash away foreign matters, is the office of
the tears. Their chief source is a conglomerate gland
placed in the upper and exterior part of the orbit. It
has numerous but very fine excretory ducts, which are
said to discharge about two ounces of tears upon each
eye during the twenty-four hours: the tears are after-
wards absorbed by the puncta lachrymalia, the function
of which may, in a certain sense, be compared to that of
the lacteals in the villous coat of the small intestines;
from the puncta they are conveyed through the snails’
horns, as they are called, into the lachrymal sac, and
thence pass into the lower meatus of the nostrils.* (A)

269. Thus much it was necessary to premise upon
the structure of the organ of vision. We now come to
the function of the organ, – to the explanation of vision.

Rays of light falling upon the cornea at an angle
more acute than forty-eight degrees, pass through it,
and, from both its density and figure, are considerably
refracted towards the axis of the eye. On entering the
aqueous humour they experience rather a less degree
of refraction.

Those rays which penetrate the pupil and are received
by the lens, are still more refracted on account of the
greater density of this medium.

The less density of the vitreous humour prevents the
focus of rays from being too small, but allows it to
fall elongated upon the retina and exhibit the image
[Seite 174] of objects, inverse indeed necessarily from the laws
of light.

270. The focus which, in this mode, falls upon the
retina, is considered acute, not absolutely but rela-
tively, on account of the different refrangibility of
colours; but the latitude arising from this aberration
of the rays is so small that it not only does not obscure
the clearness of vision in any perceptible degree, but is
the source of many advantages.*

271. The celebrated question – why we behold ob-
jects erect, while their image is painted inversely upon
the retina, may be easily answered, by considering
that objects are called inverse relatively only to those
which appear erect.

Now, since the images of all objects and of our own
bodies are painted on the retina, each in its relative
situation, this relative situation must correspond as
exactly as if they were viewed erect, so that the mind
(to which a sensation excited by the image and not the
image itself is communicated) is preserved from all
danger of error.

272. Since many conditions are required for distinct
vision, the Creator has wonderfully ordered the func-
tions of these organs.

A sufficient, but, at the same time, a definite, quan-
tity of light, not too intense for distinct vision, is pro-
vided in two modes: – First, according to the greater
or less intensity of the rays, a greater or less number
[Seite 175] of them pass to the lens; – Secondly, that portion
which is superabundant and injurious to vision, is
absorbed.

The first is effected by the motion of the iris; the
second, by the pigmentum nigrum.

273. The iris is endowed with sufficient mobility to
accommodate itself to the intensity and distance of
light, that, when exposed to a strong light or to near
objects it may expand itself and contract the pupil,
but when to a weaker light or more remote objects it
may contract itself and dilate that opening.* Physio-
logists have given different explanations of this motion.
Some ascribe it to the varied impulse of blood into its
vessels; others to contraction of its imaginary muscular
fibres. I have shewn, in a particular treatise, that
both these circumstances are impossible, and that its
proximate cause may be sought for with more proba-
bility and reason in the vita propria of the iris (42);
the more remote cause, as we formerly hinted (56), can
be solely the reaction of the sensorium.

274. The function of the dark pigment, so frequently
mentioned, (258, 261, 263,) viz. to absorb the super-
fluous rays, and its importance to the perfection of
vision, are demonstrated, among other modes, by the
dissection of different kinds of animals, and by the
diseased condition of Albinos, whose eyes are very
tender and impatient of light from the absence of this
pigment.

[Seite 176]

275. The focus of the refracted rays must fall exactly
on the retina, so that the point of vision be neither pro-
duced beyond it nor shortened enough to strike on the
vitreous body.

The latter defect exists in short-sighted persons, from
the too great convexity of the cornea or gibbosity of
the lens.

The former is the defect of long-sighted persons,
in whom there is the opposite conformation of parts.

276. Since a perfect and sound eye beholds near and
remote objects with equal distinctness, it must of neces-
sity be supplied with appropriate powers of accommo-
dation.* That these internal changes of the eye are
chiefly accomplished by the pressure of the straight
muscles of the ball, I am clearly convinced, from this
among other arguments, – that in the Greenland whale
– an amphibious animal which must see in media of
different densities, nature has most accurately provided
for it, in the remarkable structure and obsequious
flexibility of the sclerotica. (C)

277. During the waking state, the eyes are perpe-
tually, although insensibly, agitated, and directed to-
wards the axes of objects, by these muscles.

For, although the whole of the retina is sensible, it
is not all equally calculated to receive the images
of objects.

In the first place, the true axis of the human eye,
[Seite 177] where the optic nerve enters, is proved, by the well-
known experiment of Mariotte,* to be nearly insensible
to light. (D) The principal focus of the rest of the retina,
which must be considered as the chief instrument of
distinct vision, falls upon an imaginary axis of the
globe, corresponding with the axis of the cornea and
of the whole eye. This, however, as Kaestner ob-
serves in opposition to Boerhaave, is not to be under-
stood as if only one point of an object could be seen
distinctly at once, while the eye is fixed, and that, to
behold another point, the axis of the eye must be
changed; for the sensation of a complete object is
simple and complete.

278. The habit of directing the axes of the eyes
rapidly towards objects is acquired by practice. This
is proved by the example of persons who were born
blind but recovered their sight after puberty; and
of children, who seldom acquire this facility of motion
before the third month.

279. To habit we must ascribe also the circumstance
of beholding an object singly, although we have two
eyes.§ For infants at first see double, and the double
vision which occasionally remains after certain dis-
eases of the eyes may be removed by practice and
experience. (E)

280. The combined power of the two eyes does not
[Seite 178] exceed, according to Jurin, that of each, by more than
one thirteenth part.

It is needless to add, what the celebrated painter,
Leonardo da Vinci, long since remarked, – that in
viewing distant objects, it is preferable to employ but
one eye.* (F)

281. Sight can never occur unless the angle of vision
exceeds 34 seconds. This was proved by the very beau-
tiful experiments of the acute Tob. Mayer, who for-
merly was one of our number. And he demonstrated
the great excellence of the human sight, by shewing
that this still remained the limit of vision under any
light, – under the splendor of the meridian san and the
faint light of a lantern; so that vision remains almost
equally clear although the light be considerably di-
minished.

282. We may hence infer the prodigious minuteness
of the images of objects projected upon the retina,
and nevertheless impressed so forcibly upon it, that,
under certain circumstances, their vestiges remain, after
the removal of the objects from before the eye.§

NOTES.

[Seite 179]

(A) A delicate transparent membrane has been discovered by
Dr. Jacob of Dublin, between the retina and chorioid, and
adhering to both.*

(B) I am not satisfied with any account which I have hitherto
seen, of the function of the eyelids with respect to the tears.
Perhaps the tears pass over the ball of the eye as low as the edge
of the superior tarsus, which is so applied to the ball as not
ordinarily to allow of their ready escape under it. As the lids
(the under has but little motion) cover the eye during sleep and
their fine inner edges meet, the whole of the ball is at this time
readily preserved moist. But when the eyes are open, the front
of the eye between the lids would not be moistened unless the
upper tarsus occasionally descended with the fluid contained
behind it. The fluid thus brought upon the front of the eye,
trickles down, after winking, by its gravity as far as the inferior
tarsus, which also occasionally ascending a little, raises it some-
what. Winking thus preserves the front of the eye constantly
moist during the waking state.

It may be also observed that when the tarsi approximate, as
they drive before them the moisture of the front of the eye-ball,
they quite inundate the puncta lachrymalia, by which circum-
stance the puncta are of course enabled to carry off a large
quantity of the secretion, and ordinarily to prevent its overflow,
which would occur at the centre of the lower tarsus. During
sleep the puncta are not so copiously supplied, as they have only
the same share of tears as the eye in general; and there is less
occasion for it, because the removal of the stimulus of air and
light by the closure of the eyelids, lessens the secretion.

[Seite 180]

M. Majendie has found the matter of the tarsal or Meibomian
glands to be not sebaceous but albuminous, and soluble in the
tears: hence we discover why, during sleep, it accumulates on
the tarsi; – because its solvent, the tears, are not sufficiently
abundant to remove it.

(C) In Albino animals, whether the rabbit, pigeon, or mouse,
the sclerotic and chorioid are nearly transparent, the latter losing
its blood after death, and the image formed upon the retina may
be readily seen without removing a portion of the sclerotic. From
observations of this kind M. Majendie has declared that whether
the eye be presented to a neighbouring or to a distant object, the
image upon the retina is equally distinct, and therefore that all
the explanations of this circumstance which have been hitherto
given, founded on changes which can occur only during life, fall
to the ground, whether founded on pressure of the ball by the
recti muscles, motion of the crystalline, contraction of the crys-
talline or ciliary processes, &c. The iris, however, dilates when
we look at a distant, and contracts when at a near, object; as
may be distinctly observed by holding up a finger and desiring a
person to look alternately at it and at a distant object which
stands in the same line. We are conscious of this adjustment
of the iris: we move the muscle (if it may be so called) volun-
tarily, and the act is painful if quickly repeated.

M. Majendie also discovered that the escape of a little of the
aqueous or vitreous humour, or the total removal of the former
or of the cornea, impaired the distinctness of the image; the
total removal of the aqueous humour or of the crystalline also
increased the size of the image; the removal of the humours
prevented the formation of any image; an increase produced in
the pupil by a circular incision of the iris produced an increase of
the image.*

(D) Mariotte’s experiment was to make two spots upon a wall,
to fix the right eye upon the left spot, the other being closed,
[Seite 181] and gradually to retire till the right spot was no longer distin-
guishable. This is said to occur when its image falls upon the
centre of the optic nerve. I should suppose that it disappeared
at a certain distance, merely because too minute for detection
when the eye was being directed to the other spot. For the
same reason, in Picard’s variation of this experiment, by placing
an object between the eye and the spots, so that it shall appear
double and one image of it cover one spot completely when one
eye is closed, the disappearance of the spots at the time the in-
tervening object is looked at, probably arises from the one spot
being covered by it, as in truth only one eye is here employed
although both are open, and from the other spot being too dis-
tant to be visible when the attention is directed to the inter-
vening object.

(E) The notion of our originally seeing objects upside-down,
double, and all as at the same distance, is satisfactorily refuted
by Dr. Spurzheim. The organs of sight, and all the others of sense,
present, if perfect, a perfect impression to the inward senses, –
the faculties for judging of form, distance, colour, tune, &c. and
nothing farther. These do the rest. My reader must consult
Dr. Spurzheim, and particularly Mr. Coombe.

(F) Although we certainly use both eyes to look generally at
objects before us (those on each side can of course be seen by
the eye of the same side only), yet when we fix attentively on
an object, we employ but one. This at least is my own case.
If I hold up a finger, and look at distant objects, it appears
double, and if I then look at it, I of course see it single, and the
figure now seen is, in my case, that which was previously seen
with the right eye: no difference occurs in it, if now the left eye
is closed.* The greater facility of threading a needle, when both
are open, probably arises from the advantage of increasing the field
of vision while one eye is fixed steadily upon the aperture.

SECT. XVIII.
OF THE VOLUNTARY MOTIONS.

[Seite 182]

283. We have seen that the nerves perform two
offices (220) – the one of feeling, the other of moving.
The former we have already considered; we shall now
say something with respect to the latter.

284. All the motions of the body may be divided
into voluntary and involuntary.

The pulsation of the heart, and the peristaltic mo-
tion of the intestines and other viscera, are commonly
adduced as instances of involuntary motion.

The action of by far the greater number of the other
muscles is voluntary.

Respiration, sneezing, the tension of the membrana
tympani, the action of the cremaster, are regarded by
some as belonging to the former class; by others, to
the latter; and by others, as of a mixed nature.

285. If this division is narrowly examined, it will be
found embarrassed by so many difficulties that the limits
of each class cannot well be determined.

For, on the one hand, few functions can be termed
truly involuntary, especially if we consider the con-
nection of the imagination and passions with the will.

Again, on the other hand, there are few voluntary
motions that may not be rendered involuntary by the
force of habit, whose influence upon our animal mo-
tions is immense.

[Seite 183]

286. Of the latter description are those muscular
motions which, although generally voluntary, take
place, under certain circumstances, without the know-
ledge of the mind or even in opposition to its en-
deavours.

Thus we wink involuntarily, if a friend suddenly
approaches his finger to one of our eyes, though it
does not come in contact: the ring finger generally
bends if we bend the little finger.

We often unconsciously move our limbs even while
sleeping soundly.

On the contrary, some muscles which are almost
always obedient to the will, occasionally cease to be
so: an instance of this exists in the difficulty which
we experience in attempting to move the hand and foot
of the same side in different directions, and in all those
motions which, although voluntary and perfectly easy
if produced separately, are found very difficult if
attempted together.*

287. Among those motions which are supposed to be
perfectly involuntary, no one is free from exception,
as far as we know, excepting the spasms of the uterus
during labour.

With respect to the motion of the heart, we have the
indubitable testimony of Baynard and Cheyne, that
they saw the famous English officer who could stop the
motion of his heart and arteries at pleasure.

[Seite 184]

There is no question that the pulsation of the heart
and arteries may be accelerated or retarded by the
varied state of respiration.*

Rumination shews that the action of the stomach may
be voluntary, and I myself once distinctly found it so,
in a man who had the power of ruminating.

Although the motion of the iris is involuntary in most
persons, I have been credibly informed that some have
been able, by a considerable effort, to subject it to the
will and contract the pupil in a weak light.

So numerous are the motions commonly called in-
voluntary which become voluntary in some particular
individuals, especially if aided by attention and live-
liness of imagination.

Thus I have seen some able to produce at any time
a spasmodic horripilation of the skin, by representing
some unpleasant sensation to their imagination.

Others have had the power of exciting local sweat in
the hands, &c. (A)

288. This may perhaps be explained on the principle
of sensorial reaction, (56) which may be produced by
imagination – a mental stimulus, as easily as by a cor-
poreal stimulus acting upon the sensorium. (52) Many
phenomena accord admirably with this explanation;
v.c. the various causes of the erection of the penis,
and of the flow of saliva.

[Seite 185]

289. The voluntary motions are the distinguishing
characteristics of the animal from the vegetable king-
dom. For no plant has been discovered procuring for
itself food by means of voluntary motion; nor any
animal incapable of locomotion, or at least of pro-
curing sustenance by the voluntary motion of individual
members.

290. In ourselves, these motions afford a striking
proof of the intimate harmony that subsists between the
body and the mind, and is demonstrated in the rapid
and various motions of the fingers of a good per-
former on the harp, and of the vocal organs whenever
we speak.*


NOTE.

(A) Those muscles, I conceive, are called voluntary, which
we ordinarily have the power of directly contracting: those in-
voluntary, which we have not ordinarily the power of directly
contracting. These two definitions appear to me unexceptionable.

The latter does not contradict what is unquestionably true, –
that we can indirectly affect involuntary muscles, as the heart or
stomach, by thinking of certain objects, and thus exciting cer-
tain emotions; nor does the former contradict another truth, –
that voluntary muscles often contract without or against our
will. And this leads me to remark that the respiratory muscles
deserve the epithet voluntary as much as any in the body, for we
[Seite 186] directly contract them: we feel an uneasy sensation in the chest
from the retardation which occurs to the blood, and we inspire
to remove it; the uneasiness being removed, our effort ceases,
and expiration spontaneously ensues. It is true that the uneasi-
ness is so great that we are forced to inspire, and that respiration
continues while we are asleep. But the same is true of all volun-
tary muscles: – if you irritate any part of a person asleep, an
effort of some kind is made to remove it; and if you cause
strong pain or titillation in a person awake, he will be compelled,
whatever restraint he may attempt upon himself, to make an
effort to remove it by motion of some part, as forcibly as he is
compelled to remove the uneasiness in the chest by inspiration,*
and while history records examples of men standing motionless
in the midst of fire till they were consumed, we read of suicides
so determined as to have accomplished their purpose by merely
holding their breath, when deprived of access to instruments of
destruction.

SECT. XIX.
OF MUSCULAR MOTION.

[Seite 187]

291. The immediate organs of motion, by far the
most numerous in the body, are the muscles, which
form the greatest bulk among all the similar parts.

292. They abound in azote more than other animal
parts; and the departure of this principle from its
combination with hydrogen and carbon which exists
during health, entirely converts them, under a parti-
cular morbid affection* and after death, into an adi-
pocerous substance, resembling soap or spermacete.

293. The muscles are distinguished from other simi-
lar parts by two characteristic features, the one derived
from their structure, the other from their singular vital
powers.

294. This fleshy structure is so formed of moving
fibres, sui generis and of a very faint red colour, that
every muscle may be resolved into fibrous bands, these
into bundles of fibres, and these again into very fine
fleshy fibrils. (A)

295. Every muscle possesses a covering of cellular
[Seite 188] membrane,* which is so interwoven with its substance
as to surround the bands, the bundles, and even each
particular fibril.

296. Every part of the muscles is amply supplied
with blood-vessels and nervous threads. The latter
appear to deliquesce into an invisible pulp and unite
intimately with the muscular fibres: the former are so
interwoven with the fibres, that the whole muscle is
red and acquires its own paleness (294) only by being
washed.

297. Most muscles terminate in tendons, which are
fibrous parts, but so different in colour, texture, elas-
ticity, &c. as to be readily distinguished from muscles:
thus disproving the opinion of some, – that the tendi-
nous fibres originate from the muscular. This error
arose chiefly from the circumstance of the muscles of
infants containing a greater number of fleshy fibres, in
proportion to the tendinous, than those of the adult.

298. The other exclusive character of muscles (293)
is the irritability of Haller,§ the notion of which, and
its difference from contractility, we formerly explained
(41), but shall now prosecute farther.

[Seite 189]

299. This irritability, muscular power, or vis insita,
is bestowed upon all muscles, but in different degrees.*

300. The highest order are the hollow muscles which
perform the vital and natural functions, and especially
the heart, (124) whose internal surface enjoys a very
lively and permanent irritability.

Next to the heart follows the intestinal canal, parti-
cularly the small intestines, which, in warm-blooded
animals, contract after the heart has ceased to show
signs of irritability.

Next the stomach.

Then the urinary bladder, &c.

Among the other muscles, the respiratory, v.c. the
diaphragm, the intercostals, and triangularis sterni, are
remarkable for their irritability.

Then follow the remaining muscles.

Less, but still however some, exists in the ar-
teries. (128)

Also in the venous trunks contained in the thorax. (95)

Still less, if it deserve the name of irritability, in the
other blood vessels. (132)

301. Haller, the great arbitrator in the doctrine of
irritability, has ascribed it improperly (40, 5807), we
think, to some parts possessed indeed of contractility
[Seite 190] but in which I have never been able to detect genuine
irritability.

Such are the lacteals, glands, gall-bladder, uterus,
the dartos, and the penis. (B)

And others, with no less impropriety, bestow it upon
the iris, the external surface of the lungs, &c. in which
it no more exists than in the cellular membrane and
those parts which are composed of it, – the common
integuments, membranes of the brain, pleura, perito-
naeum, periosteum, medullary membrane, tendons,
aponeuroses, &c. or in the proper parenchyma of the
viscera, (20) – of the liver, spleen, kidneys, secundines,
the brain, and the rest of the nervous system, every
one of which parts is destitute alike of muscular fibre
and of what is peculiar to it, – irritability.

302. As we find muscular irritability sometimes con-
founded with the contractility of the mucous web; so,
on the other hand, some eminent men, particularly in
modem times, have attributed it to the nervous energy.*

Now, although we cannot deny the influence of the
nerves upon the muscles, most strikingly shewn of
late (225) by the experiments of the celebrated Galvani
and others, and although no muscular fibril, however
minute, can be found absolutely destitute of nervous
pulp, we are not on this account to assert that irrita-
[Seite 191] bility is not a power sui generis, as clearly different
from the nervous energy as from contractility. For
parts not muscular are not irritable, however abun-
dantly they may be supplied with nerves, as the corium,
the numerous nervous viscera; and the muscular tex-
ture alone exhibits the genuine phenomena of irrita-
bility. So that from the weight of these united argu-
ments, to omit many others, it appears more just to
assign these phenomena to the muscular fibre alone,
than to ascribe them to the nerves which are common
to so many other parts but do not in these excite the
faintest sign of irritability. We say nothing of many
weighty arguments derived, for instance, from the
facts, – that no proportion exists between the degree of
irritability and the number of nerves in any part, –
that one description of vital powers is often very ener-
getic, while the other is languid in the same individual,
according to national, morbid, or more especially to
sexual variety, &c. (C)

303. The nerves exert their influence upon the
muscles, as remote or exciting causes of their action,
but by no means as the proximate or efficient, which is
the inherent irritability of the muscles.

The passions, v.e. act upon the sensorium, this upon
the nerves of the heart, so as to excite its irrita-
bility, which produces palpitation and other anomalous
motions.

The will acts upon the sensorium, this reacts upon
the nerves of the arm, which excite muscular motion,
as remote causes; but the proximate cause is the irri-
tability of the muscles themselves.

304. With this distinction of the two causes of mus-
cular motion, the result of those experiments exactly
[Seite 192] correspond which have been so frequently made by
dividing or tying the nerves.* Paralysis ensued, but
irritability continued vigorous for a length of time
afterwards.

There have been cases where one limb was motion-
less from paralysis but retained its sensibility, while
the other was insensible but still capable of motion.
Some persons have had great pain in paralytic parts.

305. The true efficacy of the blood, so copiously
afforded to muscles, (296) in promoting their action,
is not clearly ascertained.

In the Stenonian experiment,§ indeed, paralysis of
the hind legs commonly follows the application of a
ligature upon the abdominal aorta.ǁ (D)

But after all, we are confirmed in the opinion formerly
mentioned (125), – that the action of what are com-
monly called voluntary muscles depends less than
that of the heart upon the afflux of blood to the
moving fibres; and on the contrary, more than it,
upon the influence of the nerves which excite their
irritability.

306. Besides these inherent powers common to all
muscles, there are some peculiar and adventitious,
arising from figure, situation, &c. and answering their
object with perfect accuracy.

[Seite 193]

307. From this circumstance, the muscles in general
are divided into hollow and solid. The former, as we
have seen, not directly subject to the will, belong more
to the vital and natural functions and are consequently
not to be considered at present, while we are speaking
of the voluntary muscles, which belong to the order of
animal functions.

308. Among the latter, also, there is much variety.
For, not to allude to difference of size, there is great
diversity in the disposition of their bands and fasciculi,
the direction of their fibres, the proportion of the
fleshy to the tendinous part, their course, mode of
insertion, &c.

309. The greatest number are long, and their fleshy
bellies terminate at each extremity in tendinous chords,
inert, and destitute of irritability, and fixed to the
bones, which they move in the manner of levers.

310. While a very few muscles are destitute of ten-
dons, such as the latissimus colli, an equally small
number are not inserted into bones, such are the cre-
master, as we generally find it, the azygos uvulae,
most of the muscles of the eye, &c.

311. The muscles endowed with those common
(298 sq.) and peculiar (306 sq.) powers, are thus pre-
pared to perform their actions, which also may be
divided into common and peculiar.

312. A property common to all muscles, and the im-
mediate consequence of their irritability, is to become
shorter, more rigid, and generally unequal, and, as it
were, angular, during contraction.

To attempt, with J. and D. Bernouilli and other
mathematical physicians, to reduce this diminution
to a general admeasurement, is rendered impossible,
[Seite 194] by the great difference, among other causes, between
the hollow and solid muscles in this respect, and
between the solid muscles themselves, v.c. between
straight muscles (such as the intercostals) and
sphincters.

313. The peculiar actions of muscles (311) corres-
pond with their peculiar powers, and consequently vary
so much as to be referrible to no general laws.

To cite one instance out of many, that action of cer-
tain muscles is peculiar and anomalous which sel-
dom occurs alone but nearly always subsequently to,
or simultaneously with, the action of some of a dif-
ferent order. Such is that of the lumbricales, when,
during rapid motions of the fingers, they follow the
action of other muscles of the metacarpus and fore-
arm; and of the lateral recti muscles of the eyes, either
adducens of which seldom acts, unless simultaneously
with the abducens of the other eye.

The commonly received law – that a muscle during
its contraction draws the more moveable point of
insertion to the more fixed, must be considered, as
Winslow wisely remarks,* perfectly relative and sub-
ject to various limitations. Thus, for example, some-
times the one point, and sometimes the other, may be
the more moveable; accordingly as the united action
of many different muscles may render the opposite
more fixed.

And, on the other hand, although the action of the
flexors is generally so much stronger than that of their
antagonists – the extensors, that, when the body is at
rest, the arms, fingers, &c. are a little bent, this does
[Seite 195] not so much depend upon the strength of the contrac-
tion of the flexors, as upon the voluntary relaxation
of the extensors for our own relief.

314. Every muscle has moreover a peculiar mecha-
nism
* adapted to the individual motions for which it
is intended. Besides the determinate figure of each,
many other kinds of assistance are afforded to their
peculiar motions. The bursae mucosae, chiefly found
among the muscles of the extremities; the annular liga-
ments by which some are surrounded; the fat in which
most are imbedded; the lymphatic vapour around each;
and, above all, the conformation of the sceleton,
chiefly in regard to apophyses, condyles, and articu-
lations; nay, even whole bones, v.c. the patella, the
pisiform of the carpus, and the sesamoid bones;
are destined solely to facilitate the actions of certain
muscles.

315. In this mode is compensated, or at least dimi-
nished, that inevitable loss of power which necessarily
takes place from the conformation and stature of the
whole system, in which, from the acute angle at which
some muscles are inserted or the proximity of their
insertion to the centre of motion, much of that power
is lost which would have existed, if their insertion had
been more remote or at a more obtuse angle.

316. The human body, possessing about 450 muscles,
[Seite 196] or upwards, according to sexual or individual variety,
is thus furnished with a double advantage, – with an
extreme agility of motion in particular parts and
throughout the whole, and with a surprising degree of
strength and endurance of labour. Both these are
accomplished partly by the perfection of the muscles,
which, like the perfection of ossification, takes place
at manhood; and partly by habit and practice, the
former of which in affording strength and agility to the
muscles, is demonstrated in rope-dancers, leapers,
runners, wrestlers, porters, savages, and the examples
of ancient nations.*


NOTES.

(A) Mr. Bauer discovers muscular fibres to be chains of
globules; and it is suggested that they may be constructed by
the globules of fibrine arranging themselves in lines.

(B) Irritability is the power of contracting upon the appli-
cation of a stimulus, and ceases with life. It comprehends
animal and organic contractility, (See Note to Sect. VI.) and we
must suppose the lacteals, vessels of glands, gall bladder, and
dartos to be possessed of it: the uterus will hereafter be shewn
positively to have muscular fibres, and their existence will be
rendered probable in the corpora cavernosa of the human penis.

(C) See Note F. Sect. XII.

(D) This paralysis does not show the irritability of the
[Seite 197] muscles to be impaired; they would doubtless contract immedi-
ately after this experiment, upon the application of a stimulus, as
readily as they do after apoplexy. The ligatures act immediately
by depriving the nerves of the power of stimulating them; for
a supply of arterial blood is necessary to the function of the
nervous system,* and the ligature of the abdominal aorta cuts
this off from the lower part of the spinal marrow and what
originate from it, – the nerves of the hind legs. If venous blood
is sent to the brain, death ensues, and the function of any part
is arrested by forcing venous blood into its arteries.

Another source of paralysis must ultimately arise, – the loss
of irritability from the want of circulation in the muscle.

SECT. XX.
OF SLEEP.

[Seite 198]

317. The faculties both of feeling and motion, pos-
sessed by the nervous system whose history we have
thus pursued, are so fatigued by their exertions in the
day, that rest is necessary during the night to recruit
them by means of sleep* – the image of death.

318. Sleep is a periodical function, by which the
intercourse of the mind and body is suspended, and
whose phenomena, now to be traced, correspond very
aptly with the supposition of a nervous fluid.

319. Besides other precursors of sleep, may be enu-
merated a gradually increasing dulness of the external
senses, and a relaxation of most, especially of the long,
voluntary muscles; a congestion of venous blood about
the heart, and relief afforded by yawning to the uneasy
sensation thus produced; lastly, a curious kind of short
delirium at the moment when sleep is all but present.

320. The phenomena of sleep, therefore, amount to
this, – that the animal functions are suspended, and all
the rest proceed more slowly and inactively. For the
pulse is slower, the animal heat, caeteris paribus, dimi-
nished, perspiration more sparing, digestion imperfect,
[Seite 199] and nearly all the excretions (except that of the semen,
which is indeed rather unusual) suppressed. (A)

321. The remote causes of sleep are evident.* To
say nothing of narcotics, it is induced by the expen-
diture of the animal powers from previous fatigue or
watchfulness, also by habit, darkness, silence, rest, &c.
which acquire their somniferous powers in some mea-
sure from habit, by mild, continued, and uniform im-
pressions upon certain senses, v.c. the murmur of a
rivulet or the view of a field of standing corn agitated
by the wind, a previous meal, intense cold applied to
the surface, and other modes of deriving blood from the
head, as pediluvia, clysters, profuse hemorrhages.

322. These remote causes may induce the proximate
cause, which, upon mature consideration, we think pro-
bably consists in a diminished or impeded flow of oxyge-
nated (arterial) blood to the brain, for that fluid is of the
highest importance, during the waking state, to the
reaction of the sensorium upon the senses and voluntary
motions.

[Seite 200]

The influx of blood is diminished by its derivation
from the brain and congestion in other parts; it is im-
peded by the pressure of foreign matter upon the brain,
whether from serous or purulent collections, from de-
pression of fractured bones, &c.

This diminution of, or impediment to, the flow of
blood to the brain, causes a deficiency of water in the
ventricles and a collapse of them, upon which that acute
and deep physiologist, David Hartley, whom we have
already praised, explains the various phenomena of
dreams.* Besides other phenomena which accord with
this explanation, is a very remarkable one which I
witnessed in a living person whose case was formerly
mentioned, – that of the brain sinking whenever he was
asleep and swelling again with blood the moment he
awoke.

This opinion is likewise strengthened by the produc-
tion of continued watchfulness from congestion of
blood in the head.

323. The quantity of sleep depends much upon age,
constitution, temperament, &c.; generally speaking,
much sleep is the attendant of weakness, as we find
in infants born prematurely and in superannuated per-
sons, and the very frequent source of fatuity and torpor.

[Seite 201]

324. We awake refreshed with sleep; and this return
to life is attended by the same phenomena as the
approach of sleep, – by gaping, to which is generally
associated stretching, by some degree of dulness of
the senses, &c.

325. The causes of waking correspond with those of
going to sleep.

The proximate is the more free return of blood to
the head.

The remote are (besides the power of custom, which
is in this respect very great) various stimuli applied to
the external or internal senses, either immediately affect-
ing the nervous system, as the distention of the bladder,
or mediately, by the intervention of the imagination, as
in dreaming.

326. Dreams are a sporting, as it were, of the imagi-
nation, in which it recalls the ideas of objects formerly
perceived, especially of objects of sight, and appears
to employ and interest itself with them.

It has been disputed whether dreams are natural dur-
ing health. Some believe that they always occur during
sleep, although they may escape our memory.* Others
conceive them the consequence only of derangement in
some of the abdominal viscera. Very healthy adults
have asserted that they never dreamt.

They are generally confused and irregular, but occa-
sionally discover extraordinary marks of reason.§

[Seite 202]

The power of corporeal stimulants is very great in
producing dreams; v.c. of the semen in producing las-
civious trains of ideas, of excessive repletion in causing
frightful appearances. We have one instance of a man,
in whom any kind of dreams could be induced, if his
friends, by gently addressing him, afforded the subject-
matter.* This, however, appears to be a preternatural
state, between sleeping and waking; as does also the
truly diseased case of sleep-walkers, and that affection
which seizes them with what is termed magnetic ecstasy,
which is, however, of a very different nature.

Locke and others have regarded all dreams as a spe-
cies of this mixed state. (C)


NOTES.

(A) Respiration also proceeds more slowly.

(B) It is certain that the supply of arterial blood to every
part, and especially to the nervous system, is requisite to its func-
tions and its life, and that in proportion to the activity of a
part is the activity of its supply of arterial blood. Analogy,
therefore, renders it more than probable, that, during the inac-
tivity of sleep, the brain, having less occasion for arterial blood,
has a less vigorous circulation than during the waking state; and
we know that whatever diminishes the ordinary determination of
blood to the brain (321), or impairs the movement of the blood
[Seite 203] through it,* disposes to sleep. But although this be granted,
it must be viewed not as the ordinary cause, but as a circum-
stance, or in fact a consequence, of sleep. Increase the activity
of an organ, you increase its circulation; diminish its activity,
you diminish its circulation. The alteration of circulation is
usually not the cause, but the consequence; necessary indeed to
the continuance of the altered degree of activity in the organ, but
not the cause. The degree of activity of any part, and the degree
of its circulation, are exactly and unalterably correspondent. If
the circulation through a part be mechanically increased or dimi-
nished, the sensibility and activity of the part will, doubtless, be
proportionally increased or diminished. This example occurs in
hemorrhage; frequently both are affected simultaneously, – when
diarrhoea renders the surface pale and cold, both the blood is sent
more sparingly to it, and the energy of its vessels is diminished
by the increase of energy in those of the intestines (Sect. VI.
Note.) But in ordinary sleep, the diminished circulation appears
only the consequence, for activity is always followed by inactivity.
Stimulate a muscle, separated from the body, it contracts, but it
soon refuses to do so; after a little rest, it again contracts upon
[Seite 204] the renewal of the stimulus. The case of the brain is analogous;
and when, after its daily activity, it falls asleep, the diminution
of its circulation consequently ensues.

(C) In sleep the action of the mind is considerably sus-
pended. But the degree of suspension is extremely various. In
ordinary sleep the mind is sufficiently alert to feel unpleasant
sensations and make an effort to remove their causes; – whether
to remove the uneasiness of impeded circulation in the lungs by
breathing, or to draw a way the hand when tickled. Imagination
is often active, and one idea associates with it another, consti-
tuting dreaming; but the activity of the mind is partial, and
though we are able occasionally even to reason correctly in our
dreams, we are not sufficiently ourselves to discover the incom-
patibility of many circumstances which we fancy. In a higher
degree of activity, we answer questions put to us, although often
ridiculously, as our deficiency of mental power prevents us from
keeping our associations in a proper train; and we sometimes
even perform a regular series of movements.

The great feature of sleep is the deficiency of our active
powers. If we have any external sensation, or if the imagination
riots on, presenting trains of images to our internal senses, we
reflect upon them but weakly, make great mistakes, and however
well we may reason, or whatever corporeal movement we execute,
the inferiority of our active powers is conspicuous. But that
active power is not suspended, as Mr. Dugald Stewart maintains
in his theory of dreaming,* the simple fact of breathing during
sleep, to say nothing of the other motions, and the acute, though
circumscribed, reasoning which occasionally occurs, is a suffi-
cient proof.

SECT. XXI.
OF FOOD AND HUNGER.

[Seite 205]

327. As sleep repairs the loss of the animal powers,
so food repairs that of the natural, and supplies fresh
elementary particles in the room of those which are
constantly wasting.

328. We are most effectually induced to procure and
take food by various calls of nature, all tending to the
same end: on one hand, by the intolerable torment of
hunger and thirst; and on the other, by the equally
powerful allurements of appetite.

329. Some ascribe hunger to an uneasiness arising in
the stomach from its being empty and unoccupied;
others to the mutual friction of its rugae; others not
only to the stimulus of its fluids, now secreted in abund-
ance, – of the saliva and gastric juice, but to an acri-
mony which they acquire when food is not taken in
proper time. (A)

330. Thirst appears referrible both to a very unplea-
sant dryness of the fauces, and to the particular sti-
mulus of acrid matters, especially of salts, taken by
the mouth. It may be, therefore, the consequence of
excessive absorption in the cavity of the mouth, such
as occurs when the mother applies her infant to the
breast, or, what is not uncommon, when venesection or
purging have been ordered. Violent passions fre-
quently induce thirst. (B)

[Seite 206]

331. The necessity of obeying these stimuli is greater
or less according to age, constitution, and especially
according to habit, and nothing can therefore be posi-
tively affirmed respecting its urgency; but thus much
is certain, that an healthy adult, in whom all the calls
of nature are felt in their usual force,* cannot abstain
from food a whole day without great prostration of
strength, nor scarcely beyond eight days without danger
to life. (C).

332. Although thirst is a violent desire, drink ap-
pears not very necessary to life and health; for many
warm blooded animals, – mice, quails, parrots, &c. do
not drink at all; and some individuals of the human
species have lived in perfect health and strength with-
out tasting liquids.

333. It has been disputed whether our food, by which
we satisfy these stimuli, is derived more advantageously
and the more consistently with nature from the animal
or from the vegetable kingdom.

334. Some contend that man is herbivorous, from the
shape of his teeth,§ the length of his intestines,ǁ the dif-
ference between the structure of the small and large
intestines, and from the cells of the colon. Rousseau
ingeniously urges the circumstance that woman is na-
[Seite 207] turally uniparous and provided with two breasts.* To
these arguments it may be added, that some men have
ruminated, – a power peculiar to herbivorous animals,
and that tame vegetable feeders are easily accustomed to
animal food, whereas carnivorous animals, excepting the
dog, can very seldom be brought to feed on vegetables.

The arguments of those who, with Helvetius, regard
man as carnivorous, are derived from the conformation
of his stomach, the shortnes of his coecum, &c.

335. More careful observation, however, proves that
man is not destined for either kind of food alone, but
for both. His teeth, particularly the molares, (D) and
the peculiar structure of the intestines just alluded
to, (E) hold a middle rank between the same parts in
the ferae and in herbivorous animals. The mode in
which the condyles of the lower jaw are articulated
with the temporal bones, demonstrates it in the most
striking manner (F).

336. As the human race exists in more parts of the
globe than any other kind of animal, we should have
been but ill provided for, if we had been destined to
subsist on either description of food alone; whereas
man now inhabits some countries which afford either
vegetable or animal food only.

[Seite 208]

337. Man is by far the most omnivorous of all ani-
mals, capable not only of feasting on luxurious com-
binations derived from each kingdom, but of subsisting
with health and vigour on nearly one kind of the most
simple food.

Thus, to mention a very few instances, many at pre-
sent live on vegetables only, as the tubera of solanum
(potatoes), chesnuts, dates, &c. The first families of
mankind most probably subsisted for a long period
merely on fruits, roots, corn, and pulses.*

The nomadic Moors have scarcely any other food
than gum senega. (G)

The inhabitants of Kamtschatka and many other
shores scarcely any other than fish.

The shepherds in the province of Caracas in South
America on the banks of the Oronoko, and even the
Morlachi§ in Europe, live almost entirely on flesh.

Some barbarous nations devour raw animals. This
cannot be denied to have been formerly the case with
the Samojedes,ǁ the Esquimaux,** and some tribes of
South America.††

Other nations are no less remarkable in their drink.

The inhabitants of many intertropical islands, espe-
cially in the Pacific Ocean, can procure no sweet water,
and instead of it drink the juice of cocoa-nuts.

[Seite 209]

Others take only sea-water.

Innumerable similar facts clearly prove man to be
omnivorous.


NOTES.

(A) If hunger arise from merely a sense of vacuity in the
stomach, why should it be increased by the application of cold
to the surface, the deglutition of cold liquids, &c.?

The explanation by friction of the rugae is equally unsatisfac-
tory; because the friction of these, if it does really occur, can-
not be greater than the friction of the stomach against its contents
immediately after a meal, at which time hunger does not exist.

Nor can the presence of the gastric juice explain the matter;
because, as every one knows, no mental sensation arises in any
other organ that is not excrementory, from the peculiar stimulus
of its natural fluid; and I presume that this is the stimulus
alluded to, because the mechanical stimulus from the bulk of the
gastric juice, occurs equally from the presence of food, which
does not excite hunger.

The supposition of an acrimony generated in the gastric
juice, &c. being a cause of hunger, is absurd; the fluid would be
unfit for its purposes, and would be more likely to destroy than
produce appetite.

Hunger has been attributed by some to a sympathy of the
stomach with a general feeling of want in the system. But
hunger is removed immediately that a due quantity of food is
swallowed, long before the general system can have derived
benefit from the meal; fowls are satisfied when their crops are
filled, although their food is not even ground, preparatorily to
digestion, till it has passed from the crop into the gizzard, and
ruminating animals leave off eating before they begin to chew
what they have distended their stomachs with. The circum-
[Seite 210] stance giving rise to this opinion is the continuance of hunger,
although food be taken in abundance, in cases of scirrhus pylorus
and enlarged mesenteric glands. Here, it is urged, the hunger
continues, because the body receives no nourishment. But, in
scirrhus of the pylorus, vomiting soon follows the reception of
food into the stomach, and therefore this organ is reduced to the
condition in which it was previously, and the return of hunger is
easily explicable. In diseases of the mesenteric glands, there is
in fact no obstruction to the course of the chyle. They are
found permeable (427), and the continued hunger appears rather
a part of the diseased state of the chylopoietic viscera. Besides,
many eases of imperfect nutrition, from various causes, occur
without any increase of appetite. In continued abstinence, al-
though the system is daily more in want, hunger usually ceases
in a few days, whether from the stomach falling into a state of
relaxation, becoming distended with wind, or other circumstances.

If hunger arose from fatigue of the stomach, it should be
greatest immediately after the laborious action of digestion,
and gradually decrease; but it on the contrary increases.

Were irritation the cause, hunger should be greatest when the
stomach is filled with food.

On the whole, hunger may perhaps be regarded as a sensation
connected with the contracted state of the stomach and the
corrugation of its inner coat.

It occurs when the stomach, being empty, must be contracted,
and the inner coat corrugated; and is increased by cold drink, by
cold air applied to the surface, by acids, bitters, and astringents,
– all which may be presumed to corrugate the inner coat of
the organ. It is diminished by heat and every thing which
relaxes. Again, it ceases immediately that the stomach is filled
and thus all corrugation removed, and the more the contents of
the stomach are of a nature to be absorbed or passed into the
duodenum, the sooner it recurs.

Being, in this view, a sensation connected with a local state
of the stomach, it will be affected not only by whatever affects
[Seite 211] this state, but by whatever affects also the sensibility to this state,
and therefore be subject to the common laws of sensation.
Hence uncivilized tribes enable themselves to traverse large
tracts without food by swallowing pills containing tobacco or
opium. Thus, the state of the stomach remaining the same,
hunger may diminish from the occurrence of other sensations
which attract our attention more forcibly, by passions of the
mind, &c.; as is exactly the case with all other sensations, even
with those that are morbid. – Under strong attention of the
mind either to pursuits of intellect or passion, to delightful or
painful sensation, all other sensations cease to be felt, although
really violent; and frequently, from being unattended to, do
not recur. Passions, however, may affect hunger, not only by
increasing or diminishing the sensibility to the state of the
stomach, but by increasing or decreasing this state – the cause
of the sensation.

(B) As hunger appears to depend upon the local condition of
the stomach, &c. so does thirst more evidently upon that of the
mouth and fauces. Every consideration renders it probable that
thirst is the sensation of the absence of moisture in the parts in
which it is seated. Whatever produces this, either by causing
the fluids of the mouth and fauces to be secreted in small quan-
tities or of great viscidity, or by carrying off the fluid when
secreted, produces thirst; and vice versa. To be dry means
to be thirsty, because the state is removed by directly wetting
the parts, or by supplying the system with fluid that they may be
moistened by their own secretions. Being a sensation, the same
may be repeated in regard to it as was observed respecting
hunger.

(C) ‘“Most of those,”’ says the Father of Physic, ‘“who nei-
ther eat nor drink for seven days, die within that period; and
if they survive and take nourishment, still the previous fast-
ing proves fatal.”’* A girl, however, able to eat and drink and
[Seite 212] apparently not in bad health, was extricated from the ruins
of a house at Oppido, in which she had remained eleven days
without food: an infant in her arms, but a few months old, died
on the fourth day, as the young are never so able to endure
abstinence.* A moderate supply of water lengthens life asto-
nishingly. Dr. Willan was called to a young gentleman who
had voluntarily abstained from every thing but a little water,
just flavoured with orange juice, for sixty days: death ensued a
fortnight afterwards. Pouteau mentions a young lady thirteen
years of age, that lived eighteen months and grew two inches
and a half, on syrup of capillaire and water. Redi cruelly
found that of a number of starved fowls deprived of water, none
lived beyond the ninth day, whereas one indulged with water
lived upwards of twenty.

A hog, weighing about 160 lbs. was buried in its stye under
thirty feet of the chalk of Dover Cliff for 160 days. When dug
out, it weighed but 40 lbs., and was extremely emaciated, clean,
and white. There was neither food nor water in the stye when
the chalk fell. It had nibbled the wood of the stye and eaten
some loose chalk, which from the appearance of the excrement
had passed more than once through the body.§

In abstinence equally great imbecility of mind takes place as
of body; urine may still be secreted, but the alvine discharge is
greatly diminished or suppressed altogether; the pain of hunger
ceases in a few days.

The torment of thirst increases until drink is procured or
moisture applied to the surface or inhaled: inflammation of the
mouth and throat and intense fever at length ensue.

If abstinence is not forced upon the system, but is absolutely
a part of disease, it may, like immense doses of powerful
medicines in various diseased states, be borne with wonderful
[Seite 213] indifference, and this occurs chiefly among females. The most
extraordinary case that I recollect, stated too upon unquestion-
able authority,* is that of a young Scotch woman, who laboured
under an anomalous nervous affection, and, excepting that on two
occasions she swallowed some water, received no nourishment
whatever for eight years. She passed urine enough twice a week
to wet a shilling, and for three years had no motion.

In an extraordinary instance of imperfect abstinence during
fifty years, the woman voided a little feculent matter like a piece
of roll-tobacco or a globule of sheeps’ dung, but once a year,
and that always in March, for sixteen years.

For every example of extraordinary abstinence among females,
we have a counterpart in voraciousness among males. When the
appetite is so great it is seldom nice, and not only all animals in
all states are devoured, but glass, flints, metals, sand, wood, &c.
A Frenchman named Tarare, and described by MM. Percy and
Laurent in some measure from their own observation,§ will
form a good contrast to the Scotch girl. When a lad he once
swallowed a large basket of apples after some person had agreed
to pay for them, and at another time a quantity of flints, corks,
and similar substances. The colic frequently compelled him to
apply at the Hotel Dieu; but he was no sooner relieved than he
began his tricks again, and once was but just prevented from
swallowing the surgeon’s watch, with its chain and seals. In
1789 he joined the mob and obtained sufficient food without de-
vouring for money. He was then about seventeen, weighing a
hundred pounds, and would eat five-and-twenty pounds of beef
a day. When the war broke out he entered into the army, and
devoured his comrades’ rations, as long as better supplies from
[Seite 214] other sources rendered them of little value. But when at length
his comrades stood in need of them themselves, he was nearly
famished, fell ill, and was admitted into the hôpital ambulant at
Sultzer. He there ate not only a quadruple allowance, the broken
food of the other patients, and the waste of the kitchen, but
would swallow the poultices and any thing else that came in his
way. He devoured so many dogs and cats alive that they fled
at the sight of him. Large snakes he despatched with the greatest
facility, and once gobbled up in a few moments all the dinner
that was provided for fifteen German labourers, viz. four bowls
of curd and two enormous dishes of dough boiled in water with
salt and fat. At another time he disposed of thirty pounds of
raw liver and lights in the presence of some general officers,
who, finding that he could swallow a large wooden lancet case,
took the partitions out, enclosed a letter in it, and made him swal-
low it and proceed to the enemy’s quarters for the purpose of dis-
charging it by stool and delivering the letter to a French colonel
who had fallen into the hands of the Prussians. This he con-
trived to do, enclosed the answer in it, swallowed it again,
made his escape, discharged the case again from his bowels,
washed it, and presented it to Beauharnois and the other officers.
Having, however, been well drubbed by the enemy, he refused
any further secret service und was readmitted into the hospital
to be cured of his hunger. Being no longer a novelty, less in-
terest was taken in him, and he felt it necessary to have recourse
to sheep-folds, poultry-yards, private kitchens, slaughter-houses,
and bye places where he had to contend with dogs and wolves
for their filthy food. He was detected drinking blood that had
been taken from his fellow-patients, and eating bodies in the
dead house. The disappearance of a young child excited strong
suspicions against him, and he was at length chased away and
unheard of for four years, at the end of which time he applied at
the hospice de Versailles, wasted, no longer voracious, and la-
bouring under a purulent diarrhoea, and he soon died, aged
twenty-six. The body immediately became a mass of putridity.
[Seite 215] During his life he always was offensive, hot, and in a sweat,
especially at intervals. His breath rolled off like steam, and
dejections were constantly most copious and intolerably foetid.
He was of the middle height, thin, and weak.

All the abdominal viscera were found full of suppurations.

His stomach was of immense size, and this has usually been
the case in persons habitually gluttonous. A polyphagous idiot
opened by the same writers displayed an enormous stomach,
more resembling that of a horse than of a human being: the
intestines also formed several large pouches in succession, which
appeared like additional stomachs. Cabrol dissected a glutton
of Toulouse, and found the oesophagus terminating in an exces-
sively large cavity and the intestines running, without a single
convolution, but with merely a gentle sygmoid flexure, to the
anus. We thus learn the common cause of constitutional vora-
ciousness and obtain an additional reason for referring hunger to
the want of distention of the stomach: – a great bulk of food
was required to fill these stomachs. If hunger were independent
of the distention of this organ, and connected solely with the
want of the system, an ordinary meal would have always sufficed,
as the extraordinary quantity of food could not be demanded
for nourishment, – when food enough for support had been
taken, hunger should have ceased. But hunger continued till
the stomach was filled, and the prodigious collection was dis-
posed of by abundant stools, sweating, and copious pulmonary
exhalation.

The large capacity of the stomach is generally ascribable to
original conformation, but some account for it occasionally by
repeated over-distention and the deglutition of indigestible sub-
stances, – an opinion rather improbable when we reflect that
city gluttons, who give a very fair trial to the distensibility of
their idol, never acquire such appetites and capaciousness of sto-
mach as qualify them for a show. The power of deglutition
may be very much increased by practice. We have all seen the
Indian jugglers, and I frequently conversed with a poor man who
[Seite 216] had swallowed nineteen large clasped knives at different times,
having found in a drunken fit that he could get one down his
throat for a wager:* yet in him the appetite and capacity of
stomach were not augmented.

Some great eaters are prodigies of strength; as Milo, who
killed an ox with a blow of his fist and then devoured it, and
the fellow mentioned in a thesis published at Wittemberg in 1757,
who once, in the presence of the Senate, ate up a sheep, a suck-
ing-pig, and sixty pounds of plums, stones and all, and could
carry four men a whole league upon his shoulders.

Voraciousness is of course sometimes, like depraved appetite,
but temporary and referrible to merely disordered function.
Dr. Satterly details the case of a lad in whom, while labouring
under typhus with marked inflammation in the head, the exa-
cerbations of fever were accompanied by such hunger, that he
ate every day four regular meals, each sufficient for the stoutest
labourer’s dinner, and many pounds of dry bread, biscuit, and
fruit between them. He had no sooner finished a meal than he
denied having tasted any thing, and would suck and bite the
bed-clothes or his fingers if refused more, cared nothing about
the quality of what he ate, would pass six or seven large solid
motions a day by means of physic, and ultimately recovered.
The stomach here executed its office with excessive rapidity.

(D) In carnivorous animals, the incisors are very large; and
the molares generally of an irregular wedge form, those of the
lower jaw closing in those of the upper like scissars, and being
adapted for lacerating. In the herbivorous, the surface of the
molares is horizontal or oblique, adapted for grinding.

(E) As the food of herbivorous animals requires more pre-
paration before it becomes the substance of the animal, their
stomach is adapted to retain it for a length of time. The oeso-
phagus opens nearer the right extremity of the stomach, and the
[Seite 217] pylorus nearer the left, so that a blind pouch is left on either
side. In the carnivorous, the reverse is the case, and the
stomach cylindrical, to favour the quick passage of the food.
For the same reason, the intestines in the latter, even in insects,
are generally shorter, and have fewer valvulae conniventes, and,
in some instances, no coecum.

(F) In animals which subsist on animal food, the condyles of
the lower jaw are locked in an elongated glenoid cavity, and all
rotatory motion thus prevented, as motion upwards and down-
wards is sufficient for the laceration of the food. In vegetable
feeders the joint is shallow, so that a horizontal motion is
allowed for grinding the food. For its nature in man, see
paragraph 339.

(G) In 1750, a caravan of Abyssinians had consumed all their
provisions, and would have starved but that they discovered
among their merchandise a stock of gum arabic, on which alone
a thousand persons subsisted for two months.* Yet M. Ma-
jendie found that dogs perished if fed only with gum or sugar,
olive oil, butter, and similar articles, regarded as nutritious, that
contain no azote. But although such substances be alone un-
able to nourish, yet when united with others they may afford
some support, for persons accustomed to a mixed diet generally
grow thinner, if they confine themselves to vegetable food, which
is indubitably good nourishment, and even if we grant that such
substances are not nutritious to dogs, they may be proper food
for other species; and to prove even that these are not nutritious
to dogs, the animals should have been gradually brought to feed
on them only. For animals may be brought to live on food the
most opposite to what their nature inclines them, if the change
is made insensibly: – Spallanzani made a pigeon live on flesh
and an eagle on bread; if fresh water molusca are put into sea
water, or sea water molusca into fresh water, they perish; but
[Seite 218] if the change is gradually made, they live very well;* a spider
has lived upon sulphate of zinc; the Ottomacs eat little else
than large quantities of baked earth some months of the year;
and indeed the negroes of Guinea, the Javanese, and wolves,
occasionally devour earth.

It appears that matter which has never belonged to an ani-
mated system is calculated to afford nourishment to animals in
some degree, but subordinately to matter which has belonged to
vegetables or animals, and that it alone will in some instances
support life for a time. Vegetables will indisputably live with
facility on such alone; and it has been contended that some ani-
mals, as fish, and vegetables, readily subsist and grow on simple
water, but the experiments in support of this assertion are not
quite decisive.

SECT. XXII.
OF MASTICATION AND DEGLUTITION.

[Seite 219]

338. The lower jaw is the chief organ of mastica-
tion, and is supplied, as well as the upper, with three
orders of teeth.

With incisores, generally* scalpriform for the pur-
pose of biting off small pieces, and not placed in the
lower jaw, as in other mammalia, more or less horizon-
tally, but erect, – one of the distinctive characters of the
human race.

With strong conical canine teeth, by which we divide
hard substances, and which in man neither project be-
yond the rest, nor are placed alone, but lie closely and
in regular order with the others.

With molares of various sizes, adapted for grinding,
and differing conspicuously from those of other mam-
malia, by possessing gibbous apices excessively obtuse.

[Seite 220]

339. The lower jaw is connected with the skull by a
remarkable articulation, which holds a middle rank
between arthrodia and ginglymus, and, being supplied
with two cartilaginous menisci of considerable strength,
affords an easy motion in every direction.

The digaster, assisted by the geniohyoidei and mylo-
hyodei muscles, draws the lower jaw down, when we
open the mouth.

The masseters and temporal chiefly raise it again
when we bite off any thing, and are most powerfully
contracted when we break hard substances.

Its lateral motions are accomplished by the internal
and external pterygoid.

The latter can also draw it forwards.

340. Substances are retained in the mouth and moved
and brought under the action of the teeth by the buc-
cinator, and by the tongue which is very flexible and
changeable in form. (235)

341. During manducation, there occurs a flow of
saliva,* which is a frothy fluid, consisting of a large
portion of water united with some albumen, and hold-
ing in solution a small quantity of phosphate of lime –
the source of the tartar of the teeth and of salivary cal-
culi. From being constantly applied to the tongue, it
is insipid, although it contains some microcosmic salt
(phosphate of ammonia), as well as muriatic and, inva-
riably, a small portion of oxalic, acid. It is antiseptic
and very resolvent. (A)

[Seite 221]

342. The saliva flows from three orders of conglome-
rate glands, placed laterally and interiorally with respect
to the lower jaw.

The principal are the parotids,* which pour forth
the saliva behind the middle molares of the upper jaw,
through the Stenonian ducts.

The submaxillary, through the Whartonian.§

The sublingual,ǁ – the smallest, through the numerous
Rivinian.**

343. The excretion of saliva, amounting, according
to the arbitrary statement of Nuck,†† to a pound in
twelve hours, is augmented by stimuli and by mecha-
nical pressure, or, if the expression may be allowed,
emulsion.

The latter cause, greatly favoured by the situation
of the parotids, at the articulation of the jaws, occurs
when we chew hard substances, which thus become
softened.

The former occurs when acrid substances are taken
into the mouth, which are thus properly diluted; or
arises from imagination, (288) as when the mouth waters
during the desire for food.

344. The mucus of the labial and buccal glands‡‡
and of the tongue, as well as the moisture which trans-
[Seite 222] udes from the soft parts of the mouth, is mixed with
the saliva.

345. The mixture of these fluids with a substance which
we are chewing, renders it not only a pultaceous and
easily swallowed bolus, but likewise prepares it for
further digestion and for assimilation.

346. The mechanism* of deglutition, although very
complicated and performed by the united powers of
many very different parts, amounts to this. The tongue
being drawn towards its root, swelling and growing rigid,
receives the bolus of food upon its dorsum, which is
drawn into a hollow form. The bolus is then rolled
into the isthmus of the fauces, and caught with a cu-
rious and rather violent effort by the infundibulum of
the pharynx, which is enlarged and in some measure
drawn forward to receive it. The three constrictores
muscles of the pharynx drive it into the oesophagus.
These motions are all performed in very rapid succes-
sion and require but a short space of time.

347. Nature has provided various contrivances for
opening and securing this passage.

The important motion of the tongue is regulated by
the os hyoides.

The smallest particle of food is prevented from enter-
ing the nostrils or custachian tubes, by means of the
soft palate,§ which, as well as the uvula suspended from
[Seite 223] its arch, and whose use is not clearly understood, is
extended by muscles of its own, and closes those
openings.*

The tongue protects the glottis, for the larynx at the
moment of deglutition is drawn upwards and forwards,
and in a manner concealed under the retracted root of
the tongue and applied to the latter in such a way, that
the glottis, being also constricted and protected by the
epiglottis, is most securely defended from the entrance
of foreign substances. (B)

348. Deglutition is facilitated by the abundance of
mucus which lubricates these parts, and which is af-
forded not only by the tongue (237), but by the nu-
merous sinuses of the tonsils and cryptae of the
pharynx.

349. The oesophagus, through which the food must
pass previously to entering the stomach, is a fleshy
canal, narrow and strong, mobile, dilatable, very sen-
sible, and consisting of coats resembling, except in
thickness, the coats of the other parts of the alimentary
canal.

The external coat is muscular, and possesses longi-
tudinal and transverse fibres.

The middle is tendinous, lax, more and more cellular
towards each of its surfaces, by which means it is con-
nected with the two other coats.

The interior is lined, like all the alimentary tube,
[Seite 224] with an epithelium analogous to cuticle, (176) and is
lubricated by a very smooth mucus.

350. This canal receives the approaching draught or
bolus of food, contracts upon it, propels it down-
wards, and, in the case of the bolus, stuffs it down,
as it were, till it passes the diaphragm and enters the
stomach.


NOTES.

(A) Saliva is composed of
Water 992 . 9
A peculiar animal matter 2 . 9
Mucus 1 . 4
Alkaline muriates 1 . 7
Lactate of soda and animal matter 0 . 9
Pure soda 0 . 2
––––––––
1000 . 0*

What Berzelius calls mucus, Professor Thomson and Dr. Bos-
tock regard as albumen. It is insoluble in water, and when
incinerated, but not before, yields a large portion of phosphate
of lime. The tartar of the teeth arises from its gradual decom-
position upon them, and consists of

Earthy phosphates 79 . 0
Undecomposed mucus 12 . 5
Peculiar salivary matter 1 . 0
Animal matter soluble in muriatic acid 7 . 5
––––––––
600 . 0

(B) The glottis, when sound, may be sufficiently closed inde-
pendently of the epiglottis. M. Majendie saw two persons perfectly
destitute of epiglottis who always swallowed without difficulty. –
Précis Elémentaire, T. ii. p. 63.

SECT. XXIII.
OF DIGESTION.

[Seite 225]

351. The stomach is the organ of digestion. It ex-
ists, what cannot be affirmed of any other viscus, in
perhaps all animals without exception; and, if the im-
portance of parts may be estimated in this way, evi-
dently holds the first rank among our organs.

352. The human stomach* resembles a very large
leathern bottle, is capable in the adult of containing
three pints and upwards of water, and has two open-
ings.

The superior, called cardia, at which the oesophagus,
folded and opening obliquely, expands into the sto-
mach, is placed towards the left side of its fundus.

The inferior, at which the right and narrower part
of the stomach terminates, is called pylorus, and de-
scends somewhat into the cavity of the duodenum.

353. The situation of the stomach varies accordingly
as it is in a state of repletion or depletion. When
empty, it is flaccid and hangs into the cavity of the
abdomen, its greature curvature inclining downwards,
while the pylorus, being directed upwards, forms by
doubling, an angle with the duodenum.

When full, the larger curvature is rolled forwards,
[Seite 226] so that the pylorus lies more in a line with the duode-
num, while the cardia, on the contrary, is folded, as it
were, into an angle and closed.

354. The stomach is composed of four principal
coats, separated by the intervention of three others
which are merely cellular.

The external is common to nearly all the alimentary
canal, and continuous with the omentum, as we shall
presently mention.

Within this, and united to it by cellular membrane,
lies the muscular coat, which is particularly worthy of
notice from being the seat of the extraordinary irrita-
bility (300) of the stomach. It consists of strata of
muscular fibres,* commonly divided into three orders,
one longitudinal and two circular (straight and oblique),
but running in so many directions that no exact ac-
count can be given of their course.

The third is the chief membrane. It is usually termed
nervous, but improperly, as it consists of condensed
mucous tela, more lax on its surfaces, which are united
on the one hand with the muscular and on the other
with the internal villous coat. It is firm and strong,
and may be regarded as the basis of the stomach.

The interior, (besides the epithelium investing the
whole alimentary canal) improperly called villous, is
extremely soft and in a manner spongy, porous, and
folded into innumerable rugae, so that its surface is
more extensive than that of the other coats; it exhi-
bite very small cells, somewhat similar to those larger
[Seite 227] cells which are so beautiful in the reticulum of rumi-
nants.

Its internal surface is covered with mucus, probably
secreted in the muciparous crypts which are very dis-
tinct about the pylorus.

355. The stomach is amply furnished with nerves*
from each nervous system (214), whence its great sen-
sibility, owing to which it is so readily affected by all
kinds of stimuli, whether external, as cold, or internal,
as food and its own fluids, or mental; whence also the
great and surprising sympathy between it and most
functions of the system; to which sympathy are refer-
rible the influence of all passions upon the stomach,
and of the healthy condition of the stomach upon the
tranquillity of the mind.

356. The abundance and utility of the blood-vessels
of the stomach are no less striking. Its arteries, ra-
mifying infinitely upon the cellular membrane and
glands, secrete the gastric juice, which would appear
to stream continually from the inner surface of the
stomach.

357. In its general composition this fluid is analo-
gous to the saliva, equally antiseptic, very resolvent,
and capable of again dissolving the milk which it has
coagulated.§ (A)

[Seite 228]

358. Digestion is performed principally by it. The
food, when properly chewed and subacted by the sa-
liva, is dissolved* by the gastric fluid, and converted
into the pultaceous chyme, so that most kinds of in-
gesta lose their specific qualities, are defended from
the usual chemical changes to which they are liable,
such as putridity, rancidity, &c. and acquire fresh pro-
perties preparatory to chylification. (B)

359. This important function is probably assisted by
various accessory circumstances. Among them, some
particularly mention the peristaltic motion, which, being
constant and undulatory, agitates and subdues the pul-
taceous mass of food.

The existence of a true peristaltic motion in the sto-
mach during health, is, however, not quite certain; the
undulatory agitation of the stomach which occurs, ap-
pears intended for the purpose of driving the thoroughly
dissolved portions downwards, while those portions
which are not completely subacted are repelled from
the pylorus by an antiperistaltic motion.

360. The other aids commonly enumerated, are the
pressure on the stomach from the alternate motion of
the abdomen, and the high temperature maintained in
the stomach by the quantity of blood in the neigh-
bouring viscera and blood-vessels, which tempera-
ture was at one time supposed to be of such impor-
tance, that the word coction was synonymous with
digestion.

[Seite 229]

361. To determine the time requisite for digestion
is evidently impossible, if we consider how it must vary
according to the quality and quantity of the ingesta,
the strength of the digestive powers, and the more or
less complete previous mastication.

During health, the stomach does not transmit the
digestible parts of the food before they are converted
into a pulp. The difference of food must therefore
evidently cause a difference in the period necessary for
digestion.* It may, however, be stated generally, that
the chyme gradually passes the pylorus between three
and six hours after our meals. (C)

362. The pylorus is an annular fold, consisting not,
like the other rugae of the stomach, of merely the vil-
lous, but also of fibres derived from the nervous and
muscular, coats. All these, united, form a conoidal
opening at the termination of the stomach, projecting
into the duodenum, as the uterus does into the vagina,
and, in a manner, embraced by it.


NOTES.

(A) Seven grains of the inner coat of a calf’s stomach were
found by Dr. Young to enable water poured upon it to coagulate
6857 times its weight of milk.

[Seite 230]

(B) It was once imagined that fermentation, and once that
trituration, was the cause of digestion, but as neither can produce
the same effects on food out of the body that occur in the stomach,
these opinions fell to the ground. Besides, no signs of fermen-
tation appear when digestion is perfect, and food defended from
trituration by being swallowed in metallic balls perforated to
admit the gastric juice, is readily digested.

(C) The digestive process does not go on equally through
the whole mass of food, but takes place chiefly where it is
in contact with the stomach, and proceeds gradually from the
superficies to the centre of the mass, so that the food at the
centre is entirely different in appearance from that at the
surface, and as soon as a portion is reduced to a homogeneous
consistence, it passes into the duodenum without waiting till the
same change has pervaded the whole.*

The cardiac portion of the stomach is the chief seat of the
process, and when a part of the food is tolerably digested it
passes along the large curvature to the pyloric portion, where
the process is completed. As the cardiac half is the great di-
gesting portion, it is this half that is found dissolved by the gas-
tric juice; its contents are much more fluid than those of
the pyloric half; and Dr. Philip, who by the dissection of about
a hundred and thirty rabbits has been enabled to furnish the
completest account of what goes on the stomach, relates the
case of a woman who had eaten and properly digested to the
last, but whose stomach was ulcerated every where except at the
cardiac end. Sir Everard Home found that fluids which had been
drunk were chiefly contained in the cardiac portion, and that, if
the body was examined early after death, the two portions of the
stomach were frequently in fact divided by a muscular contrac-
[Seite 231] tion.* Dr. Haighton observed the same hour-glass contraction
in a living dog, and remarked the peristaltic motion to be much
more vigorous in the pyloric half.

During digestion, the contents of the stomach acquire an acid
of a volatile nature, and, on exposure to the air, one of a more
fixed kind, probably the phosphoric.

In granivorous birds the food passes into the crop, and from
this into a second cavity from which it enters the gizzard, – a
strong muscular receptacle, lined by a thick membrane, in which,
instead of having been masticated, it is ground by means of
pebbles swallowed instinctively by the animal. Some gramini-
vorous quadrupeds with divided hoofs have four stomachs, into
the first of which the food passes when swallowed, and from this
into the second. It is subsequently returned by portions into
the mouth, chewed, and again swallowed, when, by a contraction
of the openings of the two first stomachs, it passes over them
into the third, and from this goes to the fourth. Some birds and
insects also ruminate. The stomachs of some insects and crus-
tacea contain teeth. Some zoophytes are little more than a sto-
mach: others have several openings on the surface leading by
canals that unite and run to the stomach, – a structure called by
Cuvier, mouth-root. Between the most distinct kinds of stomach
we see numerous intermediate varieties.

Vomiting cannot occur unless the stomach has the resist-
ance of the diaphragm and abdominal muscles, or of something in
their stead. Different persons have made the horrid experiment
of giving an emetic to an animal and, after the abdominal mus-
cles were cut away, observing how fruitless were all the efforts
of the stomach to reject its contents till they applied their hands
in place of these muscles, when the stomach, being forced
by the diaphragm against the resistance, instantly accomplished
[Seite 232] vomiting. M. Majendie* now claims to himself the establish-
ment of this fact, but it was proved very many years ago. Dr.
Haighton repeated such experiments with exactly M. Majendie’s
results upwards of thirty years since, and in England we have
thought the question set at rest.

SECT. XXIV.
OF THE PANCREATIC JUICE.

[Seite 233]

363. The chyme, after passing the pylorus, under-
goes new and considerable changes in the duodenum*
– a short but very remarkable portion of the intestines,
before the nutrient chyle is separated. To this end,
there are poured upon it various secreted fluids, the
most important of which are the bile and pancreatic
juice.

364. Of these we shall treat separately, beginning
with the pancreatic fluid, because it is closely allied
both in nature and function to the saliva and gastric
juice already mentioned.

365. Although it is with difficulty procured pure from
living and healthy animals, all observations made in
regard to it establish its close resemblance to the saliva.
At the present day, it would scarcely be worth while to
mention the erroneous hypotheses of F. Sylvius and
his followers – R. De Graaf, F. Schuyl,§ and others,
respecting its supposed acrimony, long since ably re-
futed by the celebrated Pechlin,ǁ Swammerdam,** and
[Seite 234] Brunner,* unless they afforded a salutary admonition,
how fatal the practice of medicine may become, if not
founded on sound physiology.

366. The source of this fluid is similar to that of the
saliva. It is the pancreas – by much the largest con-
glomerate gland in the system, excepting the breasts,
and extremely analogous to the salivary glands in every
part of its structure, even in the circumstance of its
excretory ducts arising by very minute radicles and
uniting into one common duct, which is denominated,
from its discoverer, Wirsüngian.

This duct penetrates the tunics of the duodenum, and
supplies the cavity of this intestine with a constant stil-
licidium of pancreatic juice.

367. The excretion of this fluid is augmented by the
same causes which affect that of the saliva; – pressure
and stimulus.

By the former it is emulged, whenever the stomach
lies in a state of repletion upon the pancreas.

By the latter, when fresh and crude chyme enters the
duodenum and the bile flows through the opening com-
mon to it and the pancreatic fluid.

368. Its use is to dissolve the chyme, especially if
imperfectly digested in the stomach, and at all times,
by its great abundance, to assimilate the chyme more
to the nature of the fluids and render it fitter for chyli-
fication.

SECT. XXV.
OF THE BILE.

[Seite 235]

369. The bile is secreted by the liver* – the most
ponderous and the largest of all the viscera, especially
in the foetus, in which its size is inversely as the age.
The high importance of this organ is manifested, both
by its immense supply of blood-vessels and their
extraordinary distribution, as well as by its general
existence. It is not less common to all red-blooded
animals than the heart itself.

370. The substance of the liver is peculiar, easily
distinguished at first sight from that of other viscera,
of well-known colour and delicate texture, supplied
with numerous nerves,§ lymphatics (most remarkable
on the surface),ǁ biliferous ducts, and, what these ducts
[Seite 236] arise from, blood-vessels,* which are both very nume-
rous and in some instances very large, but of different
descriptions, as we shall state particularly.

371. The first blood-vessel to be noticed is the vena
portarum,
whose dissimilarity from other veins, both
in its nature and course, was formerly hinted at. (97)
Its trunk is formed from the combination of most of
the visceral veins belonging to the abdomen, is sup-
ported by a cellular sheath called the capsule of
Glisson, and, on entering the liver, is divided into
branches which are subdivided more and more as they
penetrate into the substance of the organ, till they
become extremely minute and spread over every part.
Hence Galen compared this system to a tree whose
roots were dispersed in the abdomen and its branches
fixed in the liver.

372. The other kind of blood-vessels belonging to
the liver, are branches of the hepatic artery, which
arises from the coeliac, is much inferior to the vena
portae in size and the number of its divisions, but
spreads by very minute ramifications throughout the
substance of the organ.

373. The extreme divisions of these two vessels ter-
minate in true veins, which unite into large venous
trunks running to the vena cava inferior.

374. These extreme divisions are inconceivably mi-
nute and collected into very small glomerules,§ which
[Seite 237] deceived Malpighi into the belief that they were glan-
dular acini, hexagonal, hollow, and secretory.*

375. From these glomerules arise the pori biliarii
very delicate ducts, secreting the bile from the blood,
and discharging it from the liver through the common
hepatic duct, which is formed from their union.

376. It has been disputed whether the bile is pro-
duced from arterial or venous blood.

Although the former opinion is countenanced by the
analogy of the other secretions which depend upon
arterial blood, nevertheless more accurate investiga-
tion proves that the greater part, if not the whole, of
the biliary secretion is venous.

With respect to arguments derived from analogy, the
vena portae, resembling arteries in its distribution, may
likewise bear a resemblance to them in function.
Besides, the liver is analogous to the lungs, in
which the great pulmonary vessels are intended for
their function and the bronchial arteries for their nou-
rishment; and if we are not greatly mistaken, the use
of the hepatic artery is similar. We would, however,
by no means completely deny its importance in the
secretion of bile, but must regard it as inconsiderable,
adventitious, and not well established. (A)

377. The bile flows slowly and regularly along the
hepatic duct. The greater portion runs constantly
through the ductus communis choledochus into the
duodenum, but some passes from the hepatic into the
cystic duct, and is received by the gall-bladder, where
[Seite 238] it remains for a short period and acquires the name of
cystic bile.*

378. The gall-bladder is an oblong sac, nearly pyri-
form, adhering to the concave surface of the liver, and
consisting of three coats.

The exterior, completely covering it, derived from
the peritonaeum.

The middle, called nervous, as in the stomach,
intestines, and urinary bladder, the source of its firm-
ness and tone.

The interior, somewhat like the inner coat of the
stomach, (359) containing a net-work of innumerable
blood-vessels, abounding in mucous glands, and
marked by rugae,§ which occasionally have a beauti-
fully cancellated appearance.

379. Its cervix is conical, terminates in the cystic
duct, is tortuous, and contains a few falciform valves.ǁ

380. The bile which has passed into the gall-bladder
is retained until, from the reclined or supine posture
of the body, it flows down from it spontaneously, or
[Seite 239] is squeezed* out by the pressure of the neighbouring
jejunum, or ileum, or of the colon when distended by
faeces.

The presence of stimuli in the duodenum may derive
the bile in that direction.

The great contractility of the gall-bladder, proved
by opening living animals and by pathological pheno-
mena, although it is not true irritability (301), pro-
bly assists the discharge of bile, especially when this
fluid has, by retention, become very stimulating.

381. For the cystic bile, though very analogous to
the hepatic, (377) becomes more concentrated, viscid,
and bitter, by stagnation in the gall-bladder; the cause
of which is, in all probability, the absorption of its
more watery parts by the lymphatic vessels.

382. Our attention must now be turned to the bile
itself – a very important fluid, respecting the nature
and use of which there has been for these thirty years
more controversy than about any other fluid.

The cystic bile, being more perfect and better calcu-
lated for examination, will supply our observations.

383. Bile taken from a fresh adult subject, is rather
viscid, of a brownish green colour, inodorous, and,
if compared with that of brutes, scarcely bitter.

384. Its constituent parts obtained by chemical ana-
lysis, are, besides a large proportion of water, albu-
[Seite 240] men, resin, soda,* partly united with phosphoric,
sulphuric, and muriatic, acid, a small portion of phos-
phate of lime and iron, and a variable quantity of a
remarkable and peculiar yellow matter.

385. The composition of the bile varies greatly both
from the proportion of its parts, particularly of the
albuminous and resinous, differing under different cir-
cumstances, and also from the addition of other con-
stituents, during morbid states, especially of adipo-
cerous substances, which give origin to most biliary
calculi; for these consist either of it alone, or of it
combined with the yellow substance just mentioned. (B)

386. The nature of the bile is not saponaceous and
capable of effecting a combination between water and
oils, as Boerhaave supposed, but which opinion the
excellent experiments of Schröder, who was formerly
of this university, both confirmed and extended by
other physiologists,§ have disproved. It even decom-
poses a combination of those substances.ǁ

387. The important and various use of the bile in
chylification is self-evident.

[Seite 241]

In the first place, it gradually precipitates the faeces,
and separates the milky chyle from the mixed and
equable pultaceous chyme, while this is passing
through the tract of the small intestines, after being
propelled from the stomach into the duodenum and
diluted by the pancreatic juice.*

It separates itself into two portions, the one serous,
the other resinous. The latter combines with the faeces,
tinges them, and is discharged with them; the former
is probably mixed with the chyle and carried back to
the blood. (C)

The bile seems to act as a stimulus to the peristaltic
motion of the intestines.

We shall omit other less probable uses assigned to
the bile, v.c. of exciting hunger by regurgitating into
the stomach, – a circumstance which I think can hardly
happen during health.


NOTES.

(A) Two instances have occurred in London, of the vena
portae running, not to the liver, but immediately to the vena
cava inferior. The bile must have been secreted entirely from
the blood of the hepatic artery. One of these is described
by Mr. Abernethy, and the other is mentioned by Mr. Law-
rence.§

[Seite 242]

(B) Berzelius* states, that bile contains alkali and salts in
the same proportion as the blood, and that no resin exists in it,
but ‘“a peculiar matter, of a bitter and afterwards somewhat
sweet taste, which possesses characters in common with the
fibrin, the colouring matter, and the albumen of the blood.”’
This forms, with an excess of acid, a perfectly resinous precipi-
tate. What has been considered albumen in the bile, Ber-
zelius regards as the mucus of the gall-bladder.

Bile contains of

xxx

(C) During the precipitation of the chyle and the decom-
position of the bile, a gaseous product is usually evolved, the
mass becomes neutral, and traces of an albuminous principle
commence, strongest at a certain distance from the pylorus, –
below the point at which the bile enters the intestine, and
gradually fainter in each direction. On mixing bile with chyme
out of the body, a distinct precipitation takes place, and the
mixture becomes neutral; but the formation of an albuminous
principle is doubtful, probably from the want of the pancreatic
fluid.

It is wonderful that in jaundice, when no bile is seen in the
faeces, and according to Dr. Fordyce even in artificial obstruction
of the choledochus by ligature, nutrition continues. Life and
health are said to continue after the removal of the organ next
to be considered, – the spleen. We know little of the compen-
sating resources of nature.

SECT. XXVI.
OF THE FUNCTION OF THE SPLEEN.

[Seite 243]

388. The Spleen* lies to the left of the liver, with
which it has considerable vascular communications;
its figure is oblong; it applies itself to the contiguous
viscera, and is liable to great varieties in point of
form, number, &c.

389. Its colour is livid, its texture singular, soft,
easily lacerated, and therefore surrounded by two mem-
branes, the interior of which is proper to the spleen
and the exterior derived from the omentum.

390. The situation and size of the spleen are no less
various than its figure, and depend upon the degree of
the stomach’s repletion; for, when the stomach is
empty and lax, the spleen is turgid; when the stomach
is full, the spleen, being compressed, is emptied.

It undergoes a continual but gentle and equable
motion, dependent upon respiration, under the chief
instrument of which – the diaphragm, it is immediately
situated.

391. Its texture was formerly supposed to be cellular,
[Seite 244] and compared to the corpora cavernosa of the penis.
This opinion was proved to be erroneous by more
careful examination of the human spleen,* which con-
sists entirely of blood vessels, of enormous size in
comparison with the bulk of the organ. They are in
fact proportionably more considerable than in any other
part of the body.

392. The experiments of Wintringham demonstrate
the great tenuity and strength of the coats of the splenic
artery. It is divided into an infinite number of twigs,
the terminations of which resemble pulpy penicilli and
give rise to the splenic veins, which gradually unite
into large, loose, and easily dilatable, trunks.

393. This immense congeries of blood vessels is con-
nected and supported by a sparing cellular parenchyma,
from which the absorbents arise. The trunks of these
run along the lower surface of the spleen between the
two coats just described.

394. This loose structure of the spleen, easily be-
coming distended with blood, admirably confirms what
we formerly remarked respecting the turgor of this
organ (390). The congestion and slow return of the
splenic blood, if the nature of the neighbouring organs
is also taken into consideration, illustrates its peculiar
properties, which may throw some light upon the func-
tion of this enigmatical viscus – the source of so much
controversy.

[Seite 245]

395. The splenic blood is very fluid, coagulates with
great difficulty, separates the serum from the crassa-
mentum imperfectly, and is of a livid dark colour, like
the blood of the foetus. These circumstances clearly
demonstrate the abundance in it of carbonaceous mat-
ter; which is likewise proved indisputably by an easy
experiment. Whenever I have exposed sections of a
recent spleen to oxygen gas, they have acquired a very
bright red colour, while the air, losing its oxygen, has
become impregnated with carbon.

396. But since the spleen is the only organ of that
description quite destitute of an excretory duct except-
ing its veins which run ultimately to the liver, its func-
tion is probably subservient to that of the latter. This
opinion has appeared strengthened by the observation,
that in animals deprived of their spleen, – an expe-
riment frequently made from the most remote period,*
the cystic bile is sometimes found pale and inert.

397. At least twenty hypotheses have been framed
respecting the use of the spleen. Two more have been
lately advanced, both supposing a connection between
the spleen and stomach, but the one regarding the
spleen as a diverticulum to the blood destined to form
the gastric juice; (A) the other, supported by excel-
lent arguments and experiments, making the spleen to
receive a great portion of our drink from the cardiac
extremity of the stomach, so that these may pass
through a short cut, hitherto unknown, from the sto-
mach to the spleen, and thus into the mass of blood.
[Seite 246] The latter hypothesis, if a few objections were removed,*
would be much the most plausible of any hitherto
constructed. (B)


NOTES.

(A) This opinion was proposed a century ago, by Dr. Stukely,
Fellow of the Royal College of Physicians, London.

(B) Sir Everard Home’s friends having, among other expe-
riments, passed a ligature around the pyloric extremity of the
stomach of a dog, injected into this receptacle a solution of
rhubarb; and, on killing the animal some few hours afterwards,
none of the absorbents of the stomach were found distended, nor
could any trace of rhubarb be detected in the liver, but evident
traces existed in the spleen and in the urine. When fluids had
[Seite 247] been drunk, the spleen was turgid and exhibited cells full of a
colourless liquid, which were at other times collapsed and almost
imperceptible, – a circumstance rendering it unlikely that the
spleen is diminished in bulk by the distention of the stomach.
During the distention of the spleen, when the pylorus was not
tied, the rhubarb appeared more strongly in the blood of the
splenic than in that of other veins. If coloured solids without
fluids were introduced into the stomach, the cells of the spleen
were not distended, nor did this organ or its veins give more
signs of the colouring matter than others.

SECT. XXVII.
OF THE FUNCTION OF THE OMENTUM.

[Seite 248]

398. The omentum gastro-colicum or magnum* (to
distinguish it from the parvum or hepato-gastricum),
is a peculiar process of peritonaeum, arising imme-
diately from the peritonaeum of the stomach.

399. Although there are innumerable continuations
of the peritonaeum in the abdomen, and every abdo-
minal viscus is so covered by it that on opening the
abdomen nothing is found destitute of that membrane,
nevertheless, it is afforded in different ways, which
may be reduced to classes.

Over some the peritonaeum is merely extended, or it
affords to them only a partial covering, as is the case
with respect to the kidneys, rectum, urinary bladder,
and in some measure with respect to the pancreas and
gall-bladder.

To some which project into the cavity of the abdo-
men although adhering to its parietes, it affords a
covering for the greater part of their surface; v.c. to
the liver, spleen, stomach, uterus, and the testes of the
very young foetus.

[Seite 249]

The intestinal tube, with the exception of the rectum,
projects so much into the cavity of the abdomen, that
it is, as it were, suspended in loose processes of the
peritonaeum, called mesentery and mesocolon: the
broad ligaments of the uterus are similar to these.

400. The longest and most remarkable process of
peritonaeum, is the omentum – a large, empty, delicate,
sac, hanging from the large curvature of the stomach,
extended over the greater part of the small intes-
tines, applying itself closely to their convolutions,
and in some measure insinuating itself into their
interstices.

401. Besides the blood vessels seen upon the omen-
tum, it is marked by fatty striae or bands, every where
reticulated (whence the german name (Netzhaut) of
this membrane), which in corpulent persons increase
occasionally to a large and even dangerous size, and
by means of which the whole omentum is lubricated by
an adipose halitus.

402. On the latter circumstance depends the use
commonly ascribed to the omentum, of lubricating
the intestines and assisting their continual movements:
this also appears the use of those analogous small
bursae which are found* in such numbers about the
rectum and colon. The omentum also prevents
the adhesion of the intestines to the peritonaeum, and
the consequent impediment to the functions of the
primae viae.

403. There is another two-fold office attributed with
[Seite 250] great probability to the omentum,* viz. that of facili-
tating the dilation of the viscera to which it is conti-
guous, and of acting as a diverticulum to their blood
during their state of vacuity.

404. If we reflect on the singular structure of the
omentum parvum or hepato-gastricum especially, we
may be inclined to believe that there is another and
principal office attached to it, unknown at present, and
discoverable by comparative anatomy.

SECT. XXVIII.
OF THE FUNCTION OF THE INTESTINES.

[Seite 251]

405. The intestinal tube, over which the omentum
is extended, and which receives the chyme to elaborate
it farther (362, 363) and separate the chyle from the
faeces, is divided into two principal portions – the small
and large intestines, of whose functions we shall speak
separately.

406. The small* intestines are again divided into
three: the duodenum, jejunum, and ileum.

The first is named from its usual length.

The second from generally appearing collapsed and
empty.

The third from its convolutions: it is the longest of
the three, fuller, and, as it were, inflated, and sometimes
resembling the large intestines by the appearance of
bullae.

407. The coats of the small intestines correspond
with those of the stomach (354).

The external is derived from the mesentery.

The muscular consists of two orders of fibres: the
one longitudinal, interrupted, external, and found cspe-
cially about the part opposite the mesentery; the other,
annular and falciform, possessing the power of narrow-
[Seite 252] ing the canal, while the former shortens it. Upon both
depends the very great and permanent irritability of the
intestines, formerly mentioned (300).

The nervous coat is condensed cellular membrane,
easily reduced by handling or more particularly by in-
flation, into a spumous tela;* in it the intestinal
blood-vessels run to the mesenteric in a beauti-
fully arborescent form; the intestines, no less than
the stomach, are indebted to it for their tenacity and
strength.

The interior, lined by its delicate epithelium, and de-
serving the name of villous in the small intestines more
than in any other part of the canal, forms, in conjunc-
tion with the inner surface of the former coat, here
and there, undulated ridges and rugous plicae, which,
in dried and inflated intestines, resemble the blade of
a scythe, and are termed the valvulae conniventes or
Kerkringhianae.§

408. The villi, which are innumerableǁ upon the
inner surface of the intestines, and whose beautiful and
minute vascular structure was first carefully investi-
gated, though described with exaggeration, by Lieber-
kühn,** may be, perhaps, compared, while destitute
[Seite 253] of chyle, to little loose pendulous bags, internally soft
and spongy; but, when distended with chyle, they have
the appearance of a morel.

409. The base of these villi is surrounded by in-
numerable glandular follicles, adhering chiefly to the
nervous coat, and opening into the intestinal canal
by a very small orifice, through which they dis-
charge the mucus that lines the whole tract of the
intestines.

These are distinguished into three orders. The Brun-
nerian, largest, distinct, found in most abundance in
that part of the duodenum which is contiguous to the
pylorus.* The Peyerian, smaller, aggregated, found
chiefly at the termination of the small intestines, – about
the valve of the colon. Lastly, the Lieberkühnian,
the smallest, said to be distributed in the proportion of
about eight to each villus. The two former orders
are so inconstant, that I am inclined to consider the
view given of them in the plates alluded to, as morbid;§
for I have more than once been unable to discover the
slightest trace of fungous papillae with a single pore,
in the small intestines of healthy adults; while, on the
contrary, in aphthous subjects, I have found nearly the
[Seite 254] whole intestinal tube beset with them in infinite num-
bers, both solitary and aggregated.*

410. As the gastric juice is poured into the stomach,
so an enteric or intestinal fluid is poured into the small
intestines, demonstrated, among other ways, by the
common experiment, first, I believe, instituted by
Pechlin. It is probably of a nature similar to the
gastric liquor, but an accurate investigation of it is
a physiological desideratum. I can say nothing re-
specting its quantity, but the estimation of Haller is
certainly exaggerated, – at eight pounds in the twenty-
four hours. (A)

411. The intestines agree with the stomach in this
particular, that they have a similar, and, indeed, a more
unquestionable, or, at least, a more lively, peristaltic
action,
which occurs principally when the chymous
pulp enters them. This it agitates by an undulatory
constriction of different parts of the canal, and propels
from the duodenum towards the large intestines. Al-
though the existence of an antiperistaltic motion, caus-
ing a retrograde course to their contents, cannot be
disproved, it is in health much weaker, and less com-
mon and important, than the former.

412. By these moving powers and by these solvents
which are afforded by means of secretion, the chyme
undergoes remarkable changes.§ In the jejunum it
[Seite 255] becomes a more liquid pulp, equally mixed, of a grey
colour, and acidulous odour: in the ileum it begins to
separate into two parts-into the faeces, of a pale, yel-
lowish, brown, colour,* and nauseous smell – and the
genuine chyle, swimming upon the former, extracted
from the chyme, separated by the bile from the
faeces, and destined for absorption by the lacteal
vessels, as we shall find in the next section (A). At
present, we shall enquire what course is taken by
the faeces.

413. These, after becoming more and more inspis-
sated in their long course through the ileum, have to
overcome the valve of the colon and pass into the large
[Seite 256] intestines. To facilitate this, the extremity of the ileum
is lubricated very abundantly by mucus.

414. The valve of the colon* or, as it may deservedly
be termed after its discoverer, the valve of Fallopius,
is a short process or continuation of the portion of the
ileum that penetrates into the cavity of the large in-
testine and is surrounded by it. Its external lips, while
a neighbouring fold of the large intestine at the same
time projects considerably, are composed, not like
other similar folds, merely of the interior and ner-
vous coats, but of fibres from the muscular coat. Hence
it performs the double office of preventing the passage
[Seite 257] of too great a quantity of faeces into the large intes-
tines, and regurgitation into the small.

415. The large intestines, divided like the small into
three parts, commence by the caecum (which has a ver-
niform process
whose use in man is unknown)*, and
afford a very ample receptacle, in which the faeces
may be collected and retained till the period of their
discharge arrives.

416. They exceed the small intestines in thickness
and strength, as well as in capacity. The muscular
coat has this peculiarity – that its longitudinal fibres,
excepting at the extremity of the rectum, are collected
into three bands, called ligaments of the colon; and
the intestines themselves are divided into a kind of
prominent cells. The inner coat is not so beautifully
flocculent as in the small intestines, but more similar
to that of the stomach.

417. Their peristaltic motion is much fainter than
that of the small intestines. On the other hand, they
experience to a greater degree the pressure of the abdo-
minal parietes, to which the whole length of the colon
is contiguous.

418. They gently propel the faeces into the rectum,
which thus becomes internally stimulated to discharge
its contents. The discharge is facilitated by the ab-
sence of transverse rugae, and especially by the great
quantity of mucus at the extremity of the bowels.

419. It is principally effected by the pressure of
[Seite 258] the abdomen downwards, overcoming the resistance
of the os coccygis and of both sphincters, the inner
of which is a remarkable bundle of circular fibres,
the outer, a truly cutaneous muscle. After the excre-
tion, the effort of the abdomen having ceased, the le-
vator ani chiefly retracts the intestine, which is again
closed by its sphincter.*


NOTES.

(A) Pechlin’s experiment was simply to include a portion of
intestine between two ligatures, so that the fluid secreted into
the canal might be collected.

(B) A great part of the chyle is generally formed and absorbed
before the digested mass reaches the ileum. On arriving in the
large intestines, the mass undergoes fresh changes, at present
unexplained, and is converted into excrement. Here it is that
the true succus entericus must be poured forth.

The gas of the stomach contains, besides azote and carbonic
acid gas, oxygen, and very little hydrogen; while that of the
small intestines contains, besides the two former gases, no oxygen
and abundance of hydrogen: that of the large intestines has
less hydrogen and carbonic acid, and likewise no oxygen. Little
or no gas is found in the stomach during chymification.

The following are the results of M.M. Majendie’s and Chev-
reuil’s analysis of the gases of the alimentary canal.

In the stomach of a man just executed, –

[Seite 259]
Oxygen 11,00
Carbonic acid 14,00
Pure hydrogen 3,55
Azote 71,45
––––––
100,00

In the small intestines of a subject, four and twenty years of
age, who had eaten, two hours before execution, bread and
Gruyère cheese and drunk eau rougie, –

Oxygen 0,00
Carbonic acid 24,39
Pure hydrogen 55,53
Azote 20,08
––––––
100,00

––––– twenty-three years of age, who had eaten the
same food, and was executed with the former, –

Oxygen 0,00
Carbonic acid 40,00
Pure hydrogen 51,15
Azote 8,85
––––––
100,00

––––– twenty-eight years of age, who, four hours before
execution, had eaten beef, bread, lentils, and drunk red wine, –

Oxygen 0,00
Carbonic acid 25,00
Pure hydrogen 8,40
Azote 66,60
––––––
100,00

In the large intestines of these three criminals, were found, –

Oxygen 0,00
Carbonic acid 43,50
Carburetted hydrogen and some
traces of sulfuretted hydrogen

5,47
Azote 51,03
––––––
100,00
[Seite 260]
Oxygen 0,00
Carbonic acid 70,00
Hydrogen and pure carburetted
hydrogen
11,06
Azote 18,04
––––––
100,00

The gas of the caecum and rectum of the third was examined
separately. Caecum, –

Oxygen 0,00
Carbonic acid 12,50
Pure hydrogen 7,50
Carburetted hydrogen 12,50
Azote 67,50
––––––
100,00

Rectum, –

Oxygen 0,00
Carbonic acid 42,86
Carburetted hydrogen 11,18
Azote 45,96
––––––
100,00

Some traces of sulfuretted hydrogen appeared upon the
mercury before the last analysis was commenced.

Berzelius finds human excrement to consist of

Water 73,3
Remains of vegetable and animal
matter

7,0
Bile 0,9
Albumen 0,9
Peculiar extractive matter 2,7
Matter composed of altered bile,
resin, animal matter, &c.

14,0
Salts 1,2
––––––
100,0

The excrements of brutes have been analysed, but not to an
extent capable of affording general views.

SECT. XXIX.
OF THE FUNCTION OF THE ABSORBENT VESSELS.*

[Seite 261]

420. The chyle, which we left in the ileum just
separated from the faeces, must evidently be a mixture
of different fluids. The proportion derived from the
secretions – the saliva, bile, the gastric, pancreatic, and
enteric, fluids, surpasses, without the least doubt, that
which is derived from the aliment, although this cannot
be accurately ascertained. Hence must be derived the
solution of the problem, – how ingesta of such various
kinds can be converted into the chyle – a fluid con-
stantly of the same appearance, homogeneous, and of
an animal nature.

421. The course of the chyle from the intestines to
the blood, is through a part of the absorbent system,
which we have hitherto only hinted at, but shall now
speak of particularly. It is divided into four parts –
lacteal, and lymphatic, vessels, conglobate glands, and
the thoracic duct. Each of these will now fall under
consideration.

422. It is certain that the lacteals originate among
the villi of the internal coat of the intestines; but whe-
ther they are an immediate continuation of these villi,
or merely connected with them by a cellular medium,
[Seite 262] admits a question. I myself have never been able to
trace them so far as to discover their immediate con-
nections with the villi, but they appear to arise here
and there in the coats of the intestines, by a conspi-
cuous trunk, and we may conjecture that they take up
the chyle from the cellular structure into which it is
first drawn by the villi. This I have in fact observed
repeatedly in puppies, after making them swallow a
solution of indigo, according to the celebrated expe-
riment of Lister,* an hour or two before opening them
alive. (A)

423. The trunks just mentioned run some inches
along the surface of the intestines, under the external
coat, sometimes meandering in an angular course,
before they reach the mesentery.

424. In their course through the mesentery they run
into the mesenteric glands, of which there are two
series. The one, nearer the intestines, dispersed,
small, and resembling beans in shape; the other, nearer
the receptaculum chyli, large, and aggregated.

425. Both appear nothing more than closely-com-
pacted collections of lacteals, interwoven with innu-
merable blood-vessels, and retarding the course of the
chyle; to the end, perhaps, that it may be more inti-
mately and perfectly assimilated to an animal nature,
previously to its entrance into the thoracic duct and its
mixture with the blood. (B)

426. It has been inquired whether lacteals exist also
in the large intestines, and their existence has been
[Seite 263] contended for from the effects of particular injections,
nutrient, inebriating, &c. and also from the circumstance
that the faeces, if retained for any length of time,
become hard and dry. Although these arguments do
not demonstrate the absorption of genuine chyle below
the valve of Fallopius, nevertheless it is rendered pro-
bable by the visible existence of an abundance of
lymphatics, in the large intestines,* having the same
structure and function with the lacteals; for these
absorb lymph from the intestines, during the absence
of chyle.

But the very different structure of the internal coat
of the large intestines from that of the villous coat of
the small, strongly argues that they are not naturally
intended to absorb chyle.

427. There is another question more important and
difficult of solution, – whether all the chyle absorbed
from the small intestines passes through the thoracic
duct, or whether some enters the blood by more secret
passages?

The latter opinion rests upon very unstable argu-
ments. Thus the assertion of Ruysch, – that the me-
senteric glands become, in advanced life, indurated
and unfit for continuing their functions, was long since
disproved; and affections of these glands, swellings, &c.
are improperly called obstructions, as the glands
remain pervious, readily allowing a passage to quick-
silver. The well-known phenomenon of tepid water,
[Seite 264] injected after death into the mesenteric veins, passing
into the cavity of the intestines, has little weight with
me in regard to a function which occurs during life;
and much less weight can be allowed to the brass tube
with two legs and two branches invented by Lieberkühn
to prove the existence of these passages. (C) The
assertion – that chyle has been seen in the mesenteric
veins,* requires farther investigation and proof; so
that I cannot believe that they carry any thing more
than blood, very carbonised and destined for the for-
mation of bile. (D)

428. The ultimate trunks of the lacteals, arising,
like the lymphaties, from the combination of a great
number of small twigs, unite into the receptaculum or
cisterna chyli, – the appellation by which the lower and
[Seite 265] larger part of the thoracic or Pecquetian duct is
distinguished.

429. This duct is* a membranous canal, slender,
strong, more or less tortuous, subject to great varieties
in its course and division, destitute of muscular fibre
and nerves, and possessing here and there valves. At
about the lowest cervical vertebra, after passing the
subclavian vein, it turns back again, and is inserted
into it, being furnished with a peculiar valve at the
point of insertion.

430. The motion of the chyle throughout its course
is to be ascribed to the contractility of its containing
vessels, to their valves, and the vis-a-tergo.

431. The use of the valve placed at the opening of
the thoracic duct, is probably not so much to prevent
the influx of blood, as to modify the entrance of the
chyle into the vein, – to cause it to enter by drops.

By this contrivance, such a portion of fresh chyle
cannot have access to the blood as would stimulate the
cavities of the heart too violently and be imperfectly
and difficultly assimilated; for fresh chyle consists of
very heterogeneous elements, brought not only from
the primae viae by the lacteals, but from every part of
the body by the lymphaties.

432. These lymphatics,§ which constitute the third
[Seite 266] part of the absorbent system, and resemble the lacteals
in structure and function, are much more, and perhaps,
indeed, universally, diffused.* They arise principally
from the mucous web, which we therefore called the
grand bond of connection between the sanguiferous and
absorbing system; (27) but in great numbers likewise
from the external common integuments, from the fauces
and oesophagus, (330), the pleura and peritonaeum, and
from the thoracic and abdominal viscera.

433. Their origin is similar to that of the lacteals
in the intestines, so that the radicle of each lymphatic
absorbs the fluid from the neighbouring cellular mem-
brane, as from its territory, and propels it onwards.

434. The lymphatics have double valves, set more
or less thickly in different parts; they all enter con-
globate glands; those which are contiguous to each
other anastomose here and there; and those found on
the surface of certain viscera, as the lungs, liver, &c.
form a most beautiful network.

435. Besides other aids to their functions, evident
from what has already been said, no inconsiderable
assistance is derived from the combination of great
strength with thinness in their coats, by which they are
enabled to support a heavy column of quicksilver.
In the limbs, especially, the motion of the muscles
pressing them on every side, is highly useful in increas-
ing their power.

[Seite 267]

436. But their principal action, by which they take
up fluids more or less rapidly, eagerly absorbing some
and absolutely rejecting others,* depends upon the
peculiar modification of their vitality, and is ascribed
by the very acute Brugmans to a certain vita
propria.
(42)

437. The far greater part of these lymphatics termi-
nate in the thoracic duct; except, however, those of
the right arm, the right side of the neck, the right lung,
and the right portion of the diaphragm and liver, which
terminate in the subclavian vein of the same side.

438. From the universal existence of the lymphatics,
and especially from the great numbers on the surface,
capable of absorbing fluids from without, the heteroge-
neous nature of the lymph must be obvious; and this
is further proved by accurately examining it in different
parts of a subject; v.c. that contained in the hepatic
or splenic lymphatics is perfectly different from that in
the uterine.

439. We will enumerate the principal fluids which
are continually absorbed during health, to say nothing
of many different kinds of substances taken up during
disease. There is, besides the chyle separated from
the faeces in the small intestines, the halitus of the
cavities properly so called, especially that of the fauces
and of all the mucous tela, the fat, the more watery
[Seite 268] part of those secreted fluids which are retained for
some time in their ducts, v.c. of the milk, semen,
bile, &c. and not a small portion of the stillatitious
fluids that are applied to the common integuments.*

440. The solids, after performing their purpose in
the economy, insensibly melt away and are absorbed,
as is proved by the absorption of the greater part of
the thymus gland during infancy, of the roots of the
first teeth, and of the alveoli after the second teeth
have fallen out. The constant change of the whole
osseous system, arising from the insensible renovation
of the bony matter, of which we have treated else-
where professedly, may also be adduced.

441. It is therefore evident, since so great a variety
of matter is absorbed, and at the same time nothing
crude or improper allowed to enter the blood, that
there is a necessity for some peculiar medium to
previously subact and assimilate the various sub-
stances.

442. It appears to be the chief office of the conglo-
bate glands,
which constitute the last part of the ab-
sorbent system, to prevent the ill effects, upon the
heart, of the improper admixture of crude fluid with
[Seite 269] the blood, by assimilating the various fluids, par-
ticularly those absorbed by the skin, more and more
to an animal nature, by retarding their motion, and
perhaps also by superadding to them some fresh se-
creted fluid. (E)

443. These glands that are dispersed generally through
the body, and aggregated here and there, as in the groin
and axillae, are perfectly similar to those found in the
mesentery, consisting, like them, in a great measure, of
convoluted absorbent vessels, supplied with an im-
mense number of blood vessels, and liable to the same
diseases.*


NOTES.

(A) Dr. W. Hunter, Mr. Cruikshanks, and others, saw the
villi of the intestines perfectly white in a person who had died
soon after eating, and twenty or thirty orifices, in a single villus,
forming tubes that ran to its base and united into one trunk.

(B) If a gland is well injected, the numerous ramifications of
the absorbents prevent cells from appearing, but if injected less
minutely, cells are very evident, and distinct from the convolu-
tions and ramifications of vessels. ‘“If an absorbent gland of a
horse is filled with quicksilver and dried, and then carefully slit
open, the cells will be seen of a large size, and bristles may with
ease be passed through the openings by which they communicate.”’

[Seite 270]

It is imagined that the vasa inferentia pour their contents into
these cells, and that the efferentia afterwards absorb it from
them.

(C) Lieberkühn’s tube was of this shape: –

xxx

Water propelled into A, passed out at B and C, but not at F.
Even if F was immersed in a coloured fluid, this ascended to H,
and passed out at B with the water.

(D) M. Majendie* contends that the lacteals absorb nothing
but chyle, asserting that neither he nor Hallé have ever seen the
chyle in these vessels tinged by coloured ingesta, and that neither
he nor the veterinary surgeon Flandrin ever found any thing but
chyle enter the lacteals. Lister’s experiment has succeeded with
Blumenbach, Hunter, and numerous others, and Mr. Hunter in
the presence of several persons poured milk into the intestines
of a dog, and they all observed it quickly to fill the lacteals.
M. Majendie must pardon an Englishman for inclining to the
positive result of Hunter’s experiment, notwithstanding it failed
in his hands. Among other insignificant objections, he urges
that Mr. Hunter should have first noticed whether the ves-
sels contained chyle, whereas it is expressly mentioned that,
before the milk was poured into the intestine, the lacteals were
seen distended by a nearly colourless and pellucid fluid.

He also revives the old opinion – that the lymphatics arise from
[Seite 271] arteries only, and are destined to convey lymph from them.*
Mr. Hunter, after pouring water coloured by indigo into the
peritoneum of an animal, saw the lymphatics filled with a blue
fluid. In the hands of M.M. Majendie, Flandrin, and Dupuytren,
this experiment likewise has failed. He does, however, allow
that, in a woman who died with a collection of pus in the thigh,
the surrounding lymphatics were distended with pus to the size
of a crow’s quill; – a pretty decisive fact. The absorbents of fish
have no valves except at their termination in the red veins, and
may therefore be injected from the principal trunks: the injec-
tion passes out of the mouths of the absorbents in numerous
streams, and especially on the back, if the skate is employed; –
another decisive fact.

The ancient doctrine of veins being the organs of absorp-
tion forms a leading feature in his physiology. Mr. Hunter
deposited various fluids in the intestines, but, although he found
manifest traces of them in the absorbents, he could discover
none in the mesenteric veins. M. Majendie relates two expe-
riments in which a decoction of nux vomica, introduced into
the alimentary canal, produced its usual effects, though the
thoracic duct was tied and ascertained to be single. But, as the
poison may operate through the nervous system, these experiments
prove nothing. Even the same objection applies to a similar
experiment in which, instead of the thoracic duct being tied, the
portion of intestine containing the solution was totally sepa-
rated from the body, except in one artery and one vein. Indeed
the poison might be conveyed by absorbents in the coats of the
vessels. Another experiment appears at first sight unobjec-
tionable, because not only was every part of a limb separated
from the body except the large artery and vein, but even these
were cut asunder, quills having been previously introduced into
them and fixed to carry on the circulation, and yet some upas
plunged into the paw of the animal exerted its peculiar influence,
which besides was suspended and permitted at pleasure by com-
[Seite 272] pressing or liberating the vein under the finger and thumb. But
here again an objection presents itself, which in fact applies
likewise to all the preceding experiments: – not only has Mr. Bracy
Clarke discovered communications in the horse between the
lymphatic system and lumbar veins,* but M. Majendie allows that
the absorbents communicate with arteries, and may frequently be
injected from them: the poison might consequently on his own
admission be imagined to be taken up by lymphatics, carried into
small blood-vessels, and conveyed with the blood through the vein
to the body. Indeed, as the poison was placed in a wound, it
might contaminate the blood without being absorbed. – Against
the result of an experiment in which, after a solution of prussiate
of potass was swallowed, the salt was discoverable in the urine
and not in the lymph, M. Majendie himself supplies an objection
when treating of the urine. For he states that a minute portion
of this substance may be readily detected in the urine, while the
quantity in the blood must be large to be discoverable. As the
contents of the thoracic duct so nearly resemble blood, he should
have ascertained whether it is not difficult to detect in them also
a portion of the prussiate which would be easily manifest in the
urine. A similar experiment with a decoction of rhubarb, lies
under the same difficulty.

In starting all these doubts, I am only desirous of showing that
M. Majendie’s experiments are not so unobjectionable as he
believes, and readily grant that Mr. Hunter’s experiments deserve
repetition and the whole subject farther investigation. I am
not prepared to deny that veins absorb, or, what comes to nearly
the same thing, that there are lymphatics which do not form
trunks but convey their contents to small blood-vessels; and
I have nothing to suggest against the following facts.

‘“Three ounces of diluted alcohol were given to a dog; in a
quarter of an hour the blood of the animal had a decided smell
of alcohol; the lymph (of the thoracic duct) had none.”’

‘“In the horse, the usual contents of both the large and small
[Seite 273] intestines are mixed with a large quantity* of fluid that gradually
decreases towards the rectum and is therefore absorbed as it
passes along the canal. Now, Flandrin, having collected the
contents of the lacteals, did not find them smell like this intestinal
fluid, whereas the venous blood of the small intestines had a taste
distinctly herbaceous; that of the caecum a sharp taste and a
slightly urinous smell; and that of the colon the same qualities
in a more marked degree. The blood of other parts presented
nothing analogous.”’

‘“Half a pound of assa foetida dissolved in the same quantity of
honey was given to a horse, which was afterwards fed as usual
and killed in sixteen hours. The smell of assa foetida was per-
ceptible in the veins of the stomach, small intestines, and
caecum; but not in the arterial blood, nor in the lymph.”’
The last quotation presents as positive results in regard to
veins, as Mr. Hunter’s experiments in regard to lacteals and
lymphatics.

(E) Although some albumen is discovered actually in the
duodenum, and some fibrine in the first lacteals, the chyle is
found to contain more and more of these substances in propor-
tion to its progress towards the left subclavian vein. The chyle
contains a certain fatty matter, which is considered as incipient
albumen,
and, in proportion as this decreases, does the quantity of
fibrine and albumen increase.

SECT. XXX.
OF SANGUIFICATION.

[Seite 274]

444. There is scarcely occasion to remark that we
employ the term Sanguification to denote the assimi-
lation of the chyle to the blood, and the constant repa-
ration, by means of the former, of the constant loss
sustained by the latter.

445. The division of all our fluids into three classes –
(45) – crude, sanguineous, and secreted, turns upon this; –
that the middle class contains the stream of the vital
fluid itself, from which the numerous secreted fluids
are perpetually withdrawn, and to which, on the other
hand, there is a constant afflux of chyle and lymph
from the absorbent system.

446. But since the blood is a peculiar fluid, sui
generis,
without its fellow in nature, various assistances
and media are evidently requisite to subact and assi-
milate the heterogeneous and foreign fluids which pass
to it from the thoracic duct.

447. This is, in the first place, especially in the me-
senteric and other conglobate glands, favoured by those
windings, mentioned formerly, of the lacteals and
lymphatics, which are, at the same time, gradually more
impregnated, as it were, with an animal nature.

448. We must also take into consideration, that a
great part of the lymph which enters the left subclavian
after its admixture with the intestinal chyle in the
thoracic duct, has been derived from the substance of
[Seite 275] the viscera and other soft parts, formerly secreted from
the blood, and, therefore, already imbued with an ani-
mal nature, and easily, without doubt, again miscible
with the mass of blood, to which it does but return.

449. Something is contributed by the slow and almost
stillatitious manner in which the chyle drops into the
blood through the last valve of the thoracic duct, these
very minute portions becoming thus the more intimately
combined with the blood.

450. The heart, too, by means of the remarkable pa-
pillary muscles of the ventricles, agitates and mingles
the blood just impregnated with fresh chyle.

451. The great importance of the lungs which receive
the blood immediately after its addition of fresh chyle,
and also of respiration, in the business of assimilation,*
will be evident on considering the extraordinary vas-
cularity of those organs (14) and their constant and
regular motion.

452. The remaining part of sanguification is accom-
plished by the general circulation and the powers which
aid it, particularly by muscular motion, &c.

453. Although so many means are provided for the
combination of the chyle with the blood, and although
the constituents of the chyle somewhat resemble those
of this fluid; nevertheless, it is commonly asserted
that many hours are required for the complete change
of the colour of the chyle and for its assimilation. Be-
sides other arguments in favour of this assertion, the
pathological fact is urged, that chyle is frequently seen
[Seite 276] in blood drawn many hours after digestion. I myself
have witnessed this appearance in cases where the
blood too evidently bore an inflammatory disposition,
to use a common phrase; but I am persuaded that no
inference can be hence deduced in regard to the healthy
state, which alone is the object of physiology.


NOTE.

The fluid collected from the thoracic duct separates like the
blood into a solid and a serous portion. If formed from vege-
table food, it is nearly transparent, may be kept weeks or even
months without putrefying, and affords a faintly pink coagulum.
If from animal food, it is white and opake, begins to putrefy in
a few days, affords an opake coagulum which acquires a more
marked pink hue by the influence of the atmosphere, and throws
upon its surface a white creamy substance. The former gives
three times as much carbon as the latter; but the latter being so
much richer gives much more carbonate of ammonia and heavy
fixed oil, when subjected to the destructive distillation.* Chyle
collected from lacteals is whiter, coagulates less perfectly, and
does not acquire a red colour by exposure to the air, so that
sanguification proceeds gradually, as the chyle passes towards
the left subclavian vein, – a circumstance already stated in the
last section, Note (E). The pink colour, acquired by the coa-
gulum of chyle when exposed to the atmosphere, shews the use
of the lungs in sanguification.

Dr. Marcet has reason to believe that the appearance of creamy
matter floating in the serum of blood occurs most frequently
[Seite 277] when the food is chiefly animal, and when therefore rich chyle is
poured into the blood faster than it can be assimilated.

I lately saw a young married woman whose urine contained
very large coagula of chyle. She always dined at noon. In the
evening the coagula were white; in the morning pale with pink
streaks. After fasting twenty-four hours at my request, the coa-
gula still appeared in the urine, extremely pale, and shewing more
pink streaks. She had been some months in this way, was in
very fair health, and had a great appetite, and perhaps some other
general symptoms of diabetes; but there was no sugar in the urine.
Notwithstanding the fluid discharged seemed to present as much
coagulum as urine, the quantity of chyle proved on drying to be very
minute, and from its looseness to have been extremely distended
by the urine. As this was a state of disease, I draw no inference
from the case respecting the time necessary for the change of
chyle to blood. She would not allow me to take any blood from
the arm for observation.

Lymph is of a straw-colour and coagulates spontaneously.

SECT. XXXI.
OF NUTRITION.

[Seite 278]

454. Besides the function of the blood formerly
investigated, – of distributing oxygen through the sys-
tem and removing carbon, its principal use is to afford
nourishment to the body in general, and to the se-
creting organs the peculiar fluids which they possess
the power of deriving from it. Nutrition shall be first
examined.

455. Nutrition is the grandest gift of nature, and the
common and highest prerogative of the animal and ve-
getable kingdoms, by which these, beyond measure,
surpass, even at first sight, all human machines and
automatons. Upon these no artist can bestow the fa-
culty, not to say of increasing and of coming to perfec-
tion, but even of existing independently and repairing
the incessant losses incurred from friction.*

456. By the nutritive faculty of the body, its greatest
and most admirable functions are performed; by it we
grow from the first of our formation and arrive at man-
hood; and by it are remedied the destruction and con-
sumption which incessantly occur in our system during
life.

[Seite 279]

457. Respecting the nature of this consumption, there
has been much dispute whether it affects the solids,*
or, whether, according to some very acute writers,
these, when once formed and perfected, remain invari-
ably entire.

458. There can be no doubt that some of the similar
solids, v.c. the epidermis and nails, are gradually de-
stroyed and renewed; and the same is proved respect-
ing even the bones, by the well known experiment of
dyeing them with madder root, (A) and by the frequently
surprising attenuation of the flat bones, especially of the
skull, from defective nutrition in old age.

459. If I am not mistaken, those solid parts undergo
this successive change, which possess the reproductive
power
– an extraordinary faculty, by which not only
the natural loss of particles, but even the accidental
removal of considerable parts, from external injuries, is
repaired and perfectly supplied, as the bones§ and a
few other parts sufficiently demonstrate.

460. On the other hand, I have been led by many
experiments to the conclusion – that this genuine re-
[Seite 280] productive power appears completely bestowed upon no
similar parts which possess any other vital power besides
contractility,
i.e. irritability, sensibility, or a vita
propria.
* (B)

461. In those parts, therefore, whose vital powers
are of an higher order, the parenchyma, constituting
their base, appears permanent and is liable to this
change only, – that the interstices of the fibres and pa-
renchyma, while nutrition is vigorous, are constantly
full of nutrient animal gelatine; but when nutrition lan-
guishes, are deprived of the gelatine, collapse, and con-
sequently become thin.

462. For as the plastic lymph, the importance of
which has been frequently mentioned, is readily con-
verted into cellular membrane, so it appears to con-
stitute the principal material of the body, and, as
it were, the animal gluten, which is nourished by its
means.

463. During the growth of the body, peculiar powers
are exerted, by which the lymph deposited in the cel-
lular membrane from the blood-vessels is properly dis-
tributed and intimately assimilated to the substance of
each organ, &c. This is referrible both to the laws of
affinity, by which particles attract, and, as it were, ap-
[Seite 281] propriate others which are similar and related to them-
selves; and to the nisus formativus, which we shall
enlarge upon hereafter, and to which the proper appli-
cation of shapeless elementary matter and its modifi-
cation to particular forms, must be ascribed.

464. The union of both these powers, we conceive,
must be the source of the nutrition of such similar
parts as are not supplied with blood, but are, never-
theless, at first generated by a most powerful and in-
fallible nisus, grow, are nourished, and, if destroyed
by accident, are very easily reproduced;* such are the
nails, hairs, &c.

465. As this appears to be the true account of nutri-
tion in general, so, on the other hand, it evidently has
great varieties of degree and kind, especially where,
from the more or less lax apposition of the nutritious
matter, the structure of the similar parts is more or
less dense, and the specific weight of the whole body
more or less considerable. In this respect, not only
individuals, but whole nations, differ from each other.
The Yakuts and Burats, who are remarkable for the
lightness of their bodies, are a sufficient example of
this.

NOTES.

[Seite 282]

(A) The redness imparted to the bones by feeding animals
with madder, does not prove that the matter of the bones is con-
stantly changing; because the opinion that the madder unites
with the phosphate of lime in the blood and thus reddens all the
bony matter subsequently deposited, is erroneous. Mr. Gibson
proved, by numerous experiments, that the serum has a stronger
affinity than the phosphate of lime, for madder. The serum being
charged with madder, the phosphate of lime of the bones, al-
ready formed, seizes the superabundant madder and becomes
red. If the madder is no longer given to the animal, as it is
continually passing off with the excretions, the stronger attraction
of the serum draws it from the bones, and they re-acquire their
whiteness.*

(B) The constant renewal of the epidermis is demonstrated
by wearing black silk stockings next the skin. That the hair
and nails not only grow perpetually, but are even reproduced, is
certain from the great quantity of the former which falls off
the head whole if worn long, while a good head of hair still con-
tinues; and from the renewal of the latter, after the loss of a
good part of a finger. I lately attended a middle-aged woman,
in St. Thomas’s Hospital, who had lost nearly the whole of the
first phalanx of a finger, and yet the stump was tipped by a nail,
though certainly a clumsy one. An instance of a nail at the end
of the stump, after the complete removal of the first phalanx,
may be seen in the London Medical and Physical Journal.
Tulpius declares he has seen examples after the loss of both the
first and second phalanges (in secundo et tertio articulo). The
glans penis (in truth a mere continuation of the corpus spon-
giosum urethra;) was entirely renewed in a case described in the
Edinburgh Medical and Physical Essays.§ Nothing more can,
[Seite 283] I apprehend, be said, respecting the entire restoration of organs
in the human body. Portions of cutis, bone, membrane, blood-
vessels, absorbents, and nerves are replaced. That portions
of large nerves, fully capable of all the functions of the destroyed
pieces, are reproduced, is now a matter of certainty. Minute
blood-vessels and absorbents are of course allowed on all hands to
be produced in the cure of all solutions of continuity;* but
Dr. Parry, senior, has proved most satisfactorily that in the ram,
at least, when a blood-vessel which proceeds some way without
giving off a branch is obstructed, new branches sprout forth and
establish a communication on each side of the obstruction. The
continuance of circulation was previously attributed to the enlarge-
ment of the small anastomosing vessels. Muscle is supplied by
tendinous matter.

Brutes far surpass man in both the ordinary renewal
of the integuments and appendages, and in the extraordinary
restoration of destroyed organs. The horse periodically sheds
[Seite 284] its hair, the bird its feathers,* the stag its horns, the serpent its
cuticle, the lobster its shell and the teeth that are in its sto-
mach. The fall of the leaves of trees is an analogous circum-
stance. The extraordinary reproductive power of some brutes is
almost incredible. A lobster can reproduce a claw, a water-newt
an extremity: Blumenbach actually observed the reproduction
of the whole head with its four horns in a snail, and the com-
plete eye, – cornea, iris, crystalline lens, &c. in a water-newt.

SECT. XXXII.
OF THE SECRETIONS IN GENERAL.

[Seite 285]

466. Besides the nutritious fluids, others of various
descriptions are produced from the blood by means of
secretion, which Haller, no less than his predecessors,
with truth and regret declared to be among the most
obscure parts of physiology.*

467. The secreted fluids differ, on the one hand, so
considerably among themselves, and, on the other, have
so many points of resemblance, that their classification
cannot but be extremely arbitrary. If we arrange them
according to the degree of difference between them and
the blood from which they are formed, they will stand
in the following order. –

First, the milk, which may be in some degree consi-
dered as chyle reproduced, and appears formed by the
most simple process from the blood newly supplied
with chyle.

Next, the aqueous fluids, as they are commonly deno-
minated from their limpid tenuity, although the greater
part differ importantly from water in the nature of their
constituents, and especially in the proportion of albu-
men: such are the humours of the eye, the tears, in all
probability the vapour contained in the cellular inter-
stices and the cavities of the abdomen and thorax;
[Seite 286] nearly similar, also, is the fluid of the pericardium and
of the ventricles of the brain.

The liquor amnii of pregnancy, and the urine, re-
markable for the peculiar nature and mixture of its
proper constituents, are generally enumerated among
these.

The salivary fluids, concerned in mastication, diges-
tion, and chylification, appear more elaborated.

Next the mucous, which line the cavities of most of
the organs performing the natural and genital func-
tions, and likewise the tract of the nostrils, larynx, and
trachea.

The mucus within the eye, and under the epidermis,
is nearly similar.

In the same class may be included the cerumen of
the ears, the unguent of the Meibomian glands and of
the joints, and, perhaps, the nameless fluid poured forth
into the vagina during the venereal oestrum.

The adipose are, besides the common fat, the medulla
of the bones and grease of the skin.

Related to these are the secretion of the corona
glandis under the preputium, and of the external female
genitals.

The truly serous, or albuminous, are the fluid of the
ovarian vesicles of De Graaf, and the liquor of the
prostate.

The semen virile and the bile are each sui generis. (A)

468. It is obvious that so great a variety of secreted
fluids cannot be secreted from the mass of blood in the
same way, nor by similar organs. They differ ex-
tremely from each other in the simplicity or complexity
of their preparation.

469. The most simple mode of secretion is diape-
[Seite 287] desis, or transudation; which is the case with the fat
and the bony fluid.*

470. Secretion by glands is more complicated. Such
is considered the secretion even by follicles and cryptae,
which are found, v.c. in some parts of the corium, the
fauces, and aspera arteria, and denominated the most
simple
glands.

Properly speaking, the conglomerate (as they are
called to distinguish them from the lymphatic conglo-
bate) are the only true secreting organs; such as the
salivary and lachrymal glands, the pancreas and
breasts. They are provided with an excretory duct
coming immediately from the large lobes, which are
composed of others, smaller, and so intricate in their
structure as to have been the source of warm disputes
in the schools of medicine. Malpighi considered the
[Seite 288] miliary globules, which are easily discoverable in most
glands, as acini internally excavated. Ruysch, on the
contrary, contended that these supposed hollow acini
were nothing more than glomerules of blood vessels, –
an opinion far more consistent with microscopical
observation and the effects of minute injection.

471. The structure of some secreting organs, espe-
cially of the liver and kidneys, the latter of which
strikingly exhibit the glomerules of Ruysch or the acini
of Malpighi, are not, excepting in their peculiar paren-
chyma, very dissimilar from this structure, and indeed
throw considerable light upon the question. On the
outer part of these, small twigs arise from the sides of
the capillary arteries and run into vascular glomerules,
hanging like granules as from stalks: from these arterial
glomerules spring both very minute colourless secreting
vessels whose origin from the extremities of arteries
was formerly alluded to (92), and the radicles of veins
into which the arteries are continued, and which convey
back into the venous trunks the remaining blood de-
prived of the secreted fluid.*

472. The organisation of some other secreting parts
is evidently peculiar, v.c. of the testes, which are com-
posed of very long and numerous vessels, closely com-
pacted, &c.

473. That the different nature of the secreted fluids
depends not so much on the size and external form of
the secreting organs as upon their interior structure and
corresponding vital powers, is rendered probable by
[Seite 289] the example of many of our fluids, which, although
secreted by organs at first sight very different from
each other, have considerable resemblance to each
other in nature; v.c. the saliva and gastric juice. And
comparative anatomy teaches us, that the same fluids
are formed by organs very different in external appear-
ance, in different animals.* (C)

474. We shall now investigate the causes why par-
ticular fluids are found in particular organs, – the most
difficult part of the doctrine of secretion, and still open
to many doubts.

475. There can be no question that the absolute
cause of the variety of secretions is referrible to the
intimate nature of the secreting organ. This depends,
in the conglomerate glands and secreting viscera espe-
cially, both upon the direction and distribution of the
secreting blood-vessels, and upon the peculiar paren-
chyma
of each secreting organ, in some instances dis-
tinguishable at first sight from the substance of every
other part. (20)

476. It is likewise probable, and indisputable argu-
ments in favour of the opinion have been continually
afforded in the course of this work, that secreting
organs have not only a peculiar parenchyma, but a
vita propria – a peculiar species of vitality distinct
from the common vital powers of contractility, irrita-
bility, and sensibility. (D)

477. The absorbent system seems of much import-
[Seite 290] ance in the business of secretion. In every secreting
organ, it absorbs, for the purpose of transmission to the
blood, a fluid which is, as it were, contaminated by
the secretion of the part: v.c. a bilious fluid in the
liver; a spermatic in the testes. A constant circle
would, therefore, appear to exist in the secretory sys-
tem, so that the elements of the secretions are inces-
santly carried to the blood from the secreting organs,
and, when they return to the organs, are the more
easily attracted by a species of affinity, and draw with
them those parts of the blood whose nature is related
to their own.

478. The blood from which some secretions are pro-
duced, is endowed with peculiar qualities. The bile,
for example, is derived from blood which contains an
abundance of carbonaceous element.

479. We omit other assistances afforded to certain
secretions; v.c. congestion and derivation, so striking
in the secretion of milk, &c.

480. There is this difference among the various
fluids secreted by the organs and powers now de-
scribed, – that some pass to the place of their desti-
nation immediately, while others are deposited in re-
ceptacles, and detained there for a length of time,
becoming more perfect before their excretion. The
milk in its ducts, the urine, bile, and semen in their
respective bladders, and in some degree the serum of
the vesicles of De Graaf, are examples of this.


NOTES.

[Seite 291]

(A) ‘“There are two classes of secreted fluids, viz. the secre-
tions,
properly so called, or the fluids intended to fulfil some
ulterior purpose in the animal economy, and the excretions, which
are directly discharged from the body. The fluids of the former
class are all alkaline, and of the latter all acid. The excretions
are the urine, the perspired fluid, and the milk. All the other
fluids appear to belong to the former class.’

‘“The alkaline secreted fluids may be divided into two very
distinct species. The former of these contains the same quantity
of water as the blood, so that the change induced by the nervous
influence, seems to be confined to that of altering the chemical
form of the albuminous materials,* without affecting their
relative proportion to the water and other substances dissolved in
the blood. The bile, spermatic fluid, &c. are of this kind. The
latter species consists of fluids, in which the influence of the
nervous system has separated a large portion of the albuminous
matter, and left the remaining liquid proportionally watery.
The saliva, the humours of the eye, and the effused serum of
membranes, are of this species, and in these the quantity of
salts, and in general also of alkali, is the same as in the blood.’

‘“The influence of the chemical agent of secretion is, there-
fore, chiefly spent upon the albuminous materials of the blood,
which seems to be the source of every substance that peculiarly
characterises each secretion, each of which is sui generis, and is
its principal constituent. All the other parts of the secretion
seem to be rather accidental, and to be found there only because
they were contained in the blood out of which the secretion was
formed. Therefore, in examining the secreted fluids, the chief
attention should be paid to the peculiar matter of the fluid, which
[Seite 292] varies in all. This matter sometimes retains some of the pro-
perties of albumen, at other times, none; and hence an accu-
rate analysis, shewing the quantity and nature of this peculiar
matter, is above all to be desired.’

‘“If the several secretions be supposed to be deprived of their
peculiar matter and the remainders analysed, the same residue
would be found from them all, which also would be identical
with the fluid separated from the serum after its coagulation.
Thus we should find, first, a portion soluble in alcohol, con-
sisting of the muriates of potash and soda, lactate of soda, and
of an extractive animal substance, precipitable by tannin; and
secondly, of a portion soluble only in water, containing soda
(which acquires carbonic acid by evaporation, and is separable
by acetic acid and alcohol) and another animal substance, not
extract, precipitable from its solution in cold water, both by
tannin and muriate of mercury. Sometimes a vestige of phos-
phate of soda will also be detected.’

‘“The excretions are of a more compound nature. They all
contain a free acid, which is termed lactic, and in the urine this
is mixed with the uric acid. Urine seems to contain only a
single peculiar characteristic matter; but milk has as many as
three, viz. butter, curd, and sugar of milk, which, however, seem
to be produced by different organs that mingle their fluids in the
same receptacle. The perspired fluid appears to have no peculiar
matter, but to be a very watery liquid, with hardly a vestige of
the albumen of the blood, and, in short, is the same as the
other excretory fluids would be when deprived of their peculiar
matter. If we suppose this matter taken away from those
excretions which possess it, the remaining fluid will be found
to have properties very different from the fluid part of the secre-
tions, when equally freed from their peculiar matter. That of
the excretions is acid, contains earthy phosphates, and when
evaporated, leaves a much larger residue than the fluid of the
secretions. This residue is yellowish-brown, of the consistence
of syrup, with an unpleasant sharp saline taste of the salts that it
[Seite 293] contains. It reddens litmus, is most soluble in alcohol, and this
spirituous solution contains the muriates of the blood, together
with free lactic acid, much lactate of soda (the soda being the
free alkali of the blood, neutralised by this acid), and the ex-
tractive matter, which always accompanies this neutral salt.
The part insoluble in alcohol contains a distinguishable quantity
of phosphate of soda, a little of a similar animal matter to that
found in the secretions, and also the earthy phosphates which
were held in solution by the lactic acid, and were precipitated
by the action of the alcohol. The urine possesses also a number
of other substances, which will be specified when describing this
excretion in particular.”’*

(B) It should be remembered that galvanic experiments
prove solid matter able to traverse pieces of bladder and even
of metals, wonderful and inconceivable as is the fact.

(C) Mr. Hodgson, on opening the body of a diabetic person,
found the cavity of one renal artery obliterated by an accumu-
lation of atheromatous and calcareous matter in its coats. The
glandular structure was perfectly natural. The pelvis contained
urine, and a considerable quantity of that fluid was found in
the bladder. The kidney was supplied with blood by a large
branch from one of the lumbar arteries and by the arteries of the
renal capsule.

(D) Every chemical change is a galvanic process, and secre-
tion, being a decomposition and composition, must necessarily
be connected with galvanism, which again, however, must be
completely subservient to the vital power.

SECT. XXXIII.
OF THE FAT.

[Seite 294]

481. Of most of the secreted fluids, a concise and
connected view of which was given in the last section,
distinct mention has been made in its proper place:
the rest will be described as opportunity may permit.
Two remain, which cannot be discussed in a more
proper place than the present, – at the close of our in-
quiry into the natural functions. The one – the fat, is
a part of the system (4); the other – the urine, is excre-
mentitious. We will examine each separately.

482. The fat* is an oily fluid, very similar in its
general character to vegetable oils, bland, inodorous,
lighter than water; containing, besides the two ele-
ments common to water, to the oils just mentioned, and
to wax, viz. carbon and hydrogen, sebacic acid, which
is pretty similar to the acetic.

483. When secreted from the blood and deposited in
the mucous tela, it exists in the form of drops, divided
[Seite 295] by the laminae of the tela, in a manner not unlike that
in which the vitreous humour of the eye is contained in
very similar cells.

484. The relation of fat to different parts is various.
In the first place, some parts, even those whose mucous
tela is extremely soft and delicate, never contain fat.
Such are the palpebrae and penis.

In very many parts, it is diffused indefinitely, espe-
cially in the panniculus adiposus, the interstices of the
muscles, &c.

In some few, it is always found, and appears to be
contained in certain definite spaces, and destined for
particular purposes. Such I consider the fat around
the basis of the heart:* and in the mons veneris, where
it forms a peculiar and circumscribed lump.

485. Its consistence varies in different parts. More
fluid in the orbit, it is harder and more like suet around
the kidneys.

486. It is of late formation in the foetus; scarcely
any trace of its existence is discoverable before the
fifth month after conception.

487. There have been controversies respecting the
mode of its secretion: some, as Hunter, contending
that it is formed by peculiar glands; others, that it
merely transudes from the arteries. Besides other ar-
guments in favour of the latter opinion, we may urge
the morbid existence of fat in parts naturally destitute
[Seite 296] of it; – a fact more explicable on the supposition of
diseased action of vessels, than of the preternatural
formation of glands. Thus, it is occasionally formed
in the orbits; a lump of hard fat generally fills up the
place of an extirpated testicle; and steotoms have been
found in almost every cavity of the body.

The glands which some celebrated characters have
contended secrete the fat, are not yet more than imagi-
ginary. Whatever may be the truth of this matter,
the deposition and absorption of the fat take place with
great rapidity.

488. The use of the fat is multifarious.

It lubricates the solids and facilitates their move-
ments; prevents excessive sensibility; and, by equally
distending the skin, contributes to beauty.

We pass over the particular uses of fat in certain
parts, v.c. of the marrow of the bones.

During health, it contributes little or nothing to nou-
rishment.* The modern opinion has more probability, –
that it affords a receptacle for the superfluous hydrogen,
which could not otherwise be easily evacuated. (A)


NOTE.

(A) The fattest person on record is, I believe, Lambert of
Leicester. He weighed seven hundred and thirty-nine pounds.
[Seite 297] In him rats and mice might certainly have nested, if it is true
that a Bishop of Mentz, or

‘“A Saxon Duke did grow so fat’
‘That mice, (as histories relate)’
‘Ate grots and labyrinths to dwell in’
‘His postique parts without his feeling.”’*

Excessive formation of fat may be strongly opposed by regu-
larly taking great exercise, little sleep, and little, but dry, food.
Fretfulness of temper, or real anxiety of mind, will prevent any
one from getting fat, and make any fat man thin. A passage
that occurs in the most magnificent of Shakspeare’s Roman plays
and is founded on some information of Plutarch’s, will instantly be
remembered.

Caesar. Let me have men about me that are fat;
Sleekheaded men, and such as sleep o’ nights;
Yond’ Cassius has a lean and hungry look;
He thinks too much: such men are dangerous.
Antony. Fear him not, Caesar, he’s not dangerous;
He is’a noble Roman, and well given.
Caesar. ’Would he were fatter: – But I fear him not:
Yet if my name were liable to fear,
I do not know the man I should avoid
So soon as that spare Cassius.

SECT. XXXIV.
OF THE URINE.

[Seite 298]

489. Besides the nutritious (4) fluids and those
which form a part of our system, others are superfluous
and excrementitious, commonly termed the excrements
of the second digestion, and are of two orders. The
one exhaled by perspiration, of which we treated
formerly; the other – the urine, streaming from the
kidneys.

490. The kidneys* are two viscera, situated at the
upper part of the loins on each side, behind the perito-
naeum; rather flattened; more liable than any other
organ to varieties of figure and number; suspended
by the emulgent vessels, which are excessively large
in proportion to them; and imbedded in sebaceous
fat. (485)

491. They are enveloped in a membrane of their
own, which is beautifully vascular; and each, espe-
cially during infancy, consists of eight, or rather more,
smaller kidneys, each of which again consists, as Ferrein
asserts, of seventy or eighty fleshy radii, denominated
by him pyramides albidae.

[Seite 299]

492. A kidney, if divided horizontally, presents two
substances; the exterior, called cortex; the interior,
medulla.

Each abounds in blood vessels, but the cortical por-
tion has likewise very minute colourless vessels which
secrete the urine;* the medullary part contains those
which carry it off.

These secreting ducts, arising from the arteries in the
manner formerly described, (471) are united with glome-
rules which adhere to the cortical part and constitute
the greatest portion of it. They may be readily dis-
tinguished by their angular course from the excreting
or Bellinian tubes, in which they terminate. These,
pursuing a straight course, run from the cortical to the
medullary substance, which principally consists of
them, and, after they have coalesced into fewer trunks,
their mouths perforate, like a sieve, the papillae of the
pelvis of the organ.

493. These papillae usually correspond in number
with the lobes which form the kidneys, and they convey
the urine, secreted in the colourless vessels of the cortex
and carried through the Bellinian tubes of the medulla,
into the infundibula, which finally unite into a com-
mon pelvis.

494. The pelvis is continued into the ureters, which
are membranous canals, very sensible, lined with mucus,
extremely dilatable, generally of unequal size in the
[Seite 300] human subject in different parts,* and inserted into the
posterior and inferior surface of the bladder in such a
way, that they do not immediately perforate its sub-
stance, but pass a short distance between the muscular
and nervous coats, which at that part are rather thicker
than elsewhere, and finally open into its cavity by an
oblique mouth. This peculiarity of structure prevents
the urine from regurgitating into the ureters from the
bladder. (A)

495. The urinary bladder, varying in shape accord-
ing to age and sex, is generally capable, in the adult,
of containing about two pounds of urine. Its fundus,
which in the foetus terminates in the urachus, is covered
posteriorly by the peritonaeum. The other coats cor-
respond with those of the stomach.

The muscular consists of interrupted bands of fleshy
fibres, variously decussated, and surrounding the blad-
der. These are usually called the detrusor urinae:
the fibres which imperfectly surround the neck and are
inconstant in origin and figure, have received the appel-
lation of sphincter.

The nervous chiefly imparts tone to this membranous
viscus.

The interior, abounding in cribriform follicles,§ is
lined with mucus, principally about the cervix.

496. The urine conveyed to the bladder, gradually
becomes unpleasant by its quantity, and urges us to
[Seite 301] discharge it. For this purpose the urethra is given,
which varies with the sex, and will be farther consi-
dered in our account of the sexual functions.

497. The bladder is evacuated from the constriction of
the sphincter being overcome both by the action of the
detrusor (495) and by the pressure of the abdomen.
To these in men is superadded the action of the acce-
leratores, which force out even the drops of urine re-
maining in the bulb of the urethra.

498. The nature of the urine varies infinitely* from
age, season of the year, the length of the period since
food or drink was last taken, the quality of the ingesta,
&c. The urine of an adult, recently made after a tran-
quil repose, is generally a watery fluid of a nidorous
smell and lemon colour, which qualities depend on a
peculiar uric substance, besides a variety of other
matters held by the water in solution and differing in
their proportion in different persons. There is a re-
markable quantity of phosphoric acid united with other
constituents, forming phosphates of soda, ammonia,
and lime. A peculiar acid – the lithic or uric, is found
in the urine only.§ (C)

NOTES.

[Seite 302]

(A) Mr. Charles Bell has described two long muscles running
from the back of the prostate gland to the orifices of the ureters.
Their action is not only to assist in emptying the bladder, but
to pull down the orifices of the ureters, thus assisting to preserve
that obliquity of insertion which the ureters have a tendency to
lose in proportion as the bladder is depleted.*

(B) Sir Everard Home observed, in his experiments on the
spleen, that colouring matters began to manifest themselves in
the urine about seventeen minutes after they were swallowed,
became gradually more evident, then gradually disappeared, and
after some hours, when the mass had unquestionably passed into
the intestines, again tinged it as strongly as ever.

(C) The following is Berzelius’s analysis of urine.

xxx
[Seite 303]

It is a common mistake even at present to ascribe, as Blumen-
bach necessarily did, the colour and smell of urine to the urea,
which is now known to be colourless and have an extremely faint,
and by no means urinous, smell. Dr. Prout has established that
urea consists of

Hydrogen .266
Carbon .799
Azote 1.866
Oxygen 1.066
–––––
4.000*
–––––

The same physician has procured from lithic acid a curious
substance which he denominates the purpuric acid.

The urine of birds is generally discharged with the faeces, and
becomes solid by exposure to the air. That of serpents is dis-
charged only once in some weeks, is of a caseous consistence,
and likewise becomes perfectly solid afterwards. Both are nearly
pure uric acid. The urine of the turtle and tortoise is also
destitute of urea, but does not contain a great deal of pure uric
acid. The analysis of the urine of brutes is highly interesting,
but is not yet either extensive or accurate.

SECT. XXXV.
OF THE GENERAL DIFFERENCES OF THE SEXES.

[Seite 304]

499. Although the functions hitherto examined
are common to both sexes, some are performed very
differently in each. The most prominent differences
shall be briefly reviewed before examining the sexual
functions, properly so called.*

500. In general, each sex has its peculiar form;
more or less striking after birth, but not very obvious
in the young foetus; for the genitals of the male and
female, at this period, are not at first sight different, on
account of the clitoris being remarkably large and
the scrotum scarcely formed. (A)

[Seite 305]

501. During infancy, the general figure is but little
different, but becomes more so as age advances, when
the round and plump breasts, the general conformation,
the delicacy, softness, and the proportionally low sta-
ture of the female, form a striking contrast with the
sinewy and robust body of the male.*

502. The relation of parts, in well-formed females,
is somewhat different from that in the male. For in-
stance, in the female the face is proportionally
smaller; the abdominal and lumbar portion of the
trunk longer; the hips broader, not, however, if well
formed, broader than the shoulders; the buttocks
larger; the legs in their descent gradually approach
the knees. (B)

503. A similar difference is remarkable in the os-
seous system. In females, the bones are, caeteris pa-
ribus, smoother and rounder, the cylindrical more slen-
der, and the flat thinner; to pass over individual dif-
ferences, v.c. the very slight prominence of the frontal
sinuses, the more elliptic edges of the alveoli, the
greater narrowness of the chest, the greater capacity
[Seite 306] on the contrary of the pelvis, the difference of the cla-
vicles, thigh bones, &c.* (C)

504. With respect to the soft parts, the female mu-
cous tela is more lax and yielding, so as to dilate more
easily during pregnancy; the skin is more delicate, and
of a clearer white, from the quantity of fat below it.

The hair of the head is commonly longer: but other
parts, which are covered with hair in men, are either
quite smooth in women, as the chest and chin; or less
hairy, as the perinaeum; or smaller in circumference,
as the pudenda; or covered with merely a very delicate
and soft down, as the arms and legs. (D)

505. Among the particular differences of function,
must be mentioned the pulse, which is, in females, cae-
teris paribus, more frequent (116); also the quantity of
blood passing to the abdomen is greater. The lungs,
on the other hand, are smaller, from the greater nar-
rowness of the chest, which is however more moveable
above. The os hyoides is much smaller; the larynx
scarcely prominent and more contracted, whence the
voice is less grave.

506. As to the animal functions, besides the greater
abundance of nerves in the organs of qeneration, the
general nervous system of females is far more mo-
bile, and the propensity to emotion stronger. On the
other hand, the muscular system is weaker, and the
muscles (with the exception of the glutei, psoae,
[Seite 307] quadrati lumborum, and a few others) proportionally
smaller. (E)

507. In regard to the natural functions, the stomach
and the appetite for food, are less;* the growth of the
body more rapid; and the periods of dentition, pu-
berty, and full growth, earlier.

508. But by far the greatest difference exists in the
genital functions, which are intended in man for im-
pregnating, and in woman for conceiving. The fuller
investigation of these now remains to be prosecuted. (G)


NOTES.

(A) Sir Everard Home has published a singular hypothesis.
He suggests that the sex is not determined at the first formation
of the individual, but that the parts of generation are originally
so situated, and of such a nature, that they are capable of be-
coming either male or female organs when the sex is subse-
quently fixed. His arguments are the following. – 1. The Testes
and Ovaria lie originally in the same situation. 2. The Clitoris
is at first of great size. 3. When the female among brute Mam-
malia has inguinal Mammae, so likewise has the male; men also
possess breasts. 4. The Scrotum occupies in the male, the place
occupied in the female by the Labia, and is of the same structure
with them. 5. The Nymphae of the female exactly correspond
[Seite 308] to the Preputium of the male. 6. Twins are usually of the same
sex, as if the same cause had influenced the generative organs of
each; when they are of different sexes, it is a common remark
that they seldom breed, nature probably having been disturbed
in her operations. 7. When among black cattle twins are pro-
duced of different sexes, that which appears the cow is really an
hermaphrodite, incapable of breeding, and vulgarly termed a free
martin; – a circumstance in every respect analogous to the pre-
ceding.* It may be added, that the round ligaments of the
female descend, like the two spermatic chords of the male, to
the abdominal ring; that marsupial bones exist, without any
function whatever, in the males of some marsupial animals; that
the hen has a Bursa Fabricii; and that the glans clitoridis of the
female opossum is bifid. Comparative anatomy furnishes many
similar facts. But the existence in both sexes of parts that
can be useful only in one, – confessed by Paley to have been
a complete puzzle to him, is now universally regarded as
merely an instance of Nature’s observance of general rides in
the formation of beings: even some species of animals have
parts that are useful only in others, and so general are the
laws of formation now found that naturalists are at this mo-
ment arranging all vegetables and animals in natural orders,
and the artificial classifications of Linnaeus are rapidly crum-
bling to dust. The resemblance of the Scrotum to the Labia,
and of the Nymphae to the Preputium, and the original iden-
tity of the situation of the testes and ovaria, may be similarly
[Seite 309] explained. The usual identity of the sex of twins still shows
only Nature’s general plans, and the frequent infecundity of
twins of different sexes only that general plans have been some-
what thwarted.

The sex of the offspring would appear determined by the fe-
male rather than by the male. Mr. Knight has observed that
individual cows, &c. however various the males, produce one sex
rather than the other, so that he has with tolerable certainty pre-
dicted the number of male and female young; while nothing
similar was ever observable in regard to his bulls, rams, &c.
Even the external appearance and the habits of brutes and vege-
tables, he has found much more, and sometimes altogether, in-
fluenced by the female. The quantity of pollen employed in the
fecundation of female plants, he found of no importance in this
respect.*

(B) The form as well as the texture of the female is more
delicate: her surface has no muscular protuberances, but is beau-
tifully rounded; her legs therefore have no calves, but, like the
arms and fingers, gently taper; her feet and hands are small;
her stature one sixth shorter than that of the male; her neck
longer. From the smaller stature and the greater size of the
abdominal and lumbar regions, it follows that the middle point
which lies at the pubes in the male, is situated higher in the
female. Her abdomen is more prominent and rounded, and her
shoulders stand less forward and distant from the trunk. Her
thighs are more voluminous and distant from each other.

(C) The greater capacity of the female pelvis, which contains
the chief organs of generation and affords a passage for the
child, arises from the greater expansion of the ossa ilei, the
larger angle of the junction of the ossa pubis, and the greater
concavity and breadth of the os sacrum: the os coccygis like-
wise is more slender and moveable. The clavicles are less bent;
the thorax more projecting, whence deeper, although narrower
and shorter; the sternum shorter and broader; the cartilago
[Seite 310] ensiformis shorter; the two superior ribs flatter. Camper re-
marks, that if the male and female forms are traced within two
ellipses of equal dimensions, the male shoulders will stand with-
out and the pelvis within, while the female shoulders will remain
within and the pelvis without.* The face and brain are abso-
lutely smaller than in men, the face likewise proportionally so;
yet such is the relative size of the cranium, that while in the
male, the head, including the teeth, is as 1 to 8 or 10, in the
female it is as 1 to 6, of the weight of the rest of the sceleton.

(D) Hen birds have a far less beautiful and copious plumage
than cocks.

An instance is related by M. Roux of a woman forty
years of age, who had one child and whose breasts were well
developed, having a strong and long beard: the lobes of her
ears were also covered with hair.

(E) Inferior to man in reasoning powers and corporeal
strength, woman possesses more sensibility of both body and
mind, more tenderness, affection, and compassion, more of all
that is endearing and capable of soothing human woes, but less
firmness of character, except indeed where affection subsists; –
although Varium et mutabile semper foemina, is a true character,
yet nothing is too irksome, too painful, or too perilous, for a
mother, a wife, or a mistress, to endure or attempt for the object
of her love.

‘“A thousand acts in every age will prove
Women are valiant in a cause they love.’
‘If fate the favoured swain in danger place,’
‘They heed not danger, – perils they embrace,’
‘They dare the world’s contempt – they brave their name’s disgrace.’
‘They on the ocean meet its wild alarms,’
‘They search the dungeon with extended arms,’
‘The utmost trial of their faith they prove,’
‘And yield the lover to assert their love.”’
[Seite 311]

(F) And beastly gluttons are generally men.

(G) All the Linnaean classes of vegetables whose sex is known,
are hermaphrodite, excepting Dioecia and in part Polygamia.
Some inferior animals also are naturally hermaphrodite; and
among others, for instance, moths, monstrous hermaphrodites
are not uncommon, each half of the body possessing the
characteristics of a different sex. There probably exists no au-
thentic account of a true hermaphrodite, capable of impregnating
and being impregnated, among mammalia. Yet occasionally
brutes of this class have perfect organs of one sex combined
with imperfect ones of the other, and both they and the human
subject each set imperfect, so as to be truly neutrumque et
utrumque.* Nor that in such combinations in the human sub-
ject at least one testis and one ovarium now and then exist, do
I at all doubt, after reading the case given by Maret, and seeing
the creature shewn here lately under the name of Lefort. In
the former, a testicle on one side and an ovarium on the other are
decidedly said to have existed, besides vesiculae seminales, a Fal-
lopian tube, a uterus, a blind vagina, and a blind penis: from
the middle upwards the general characteristics of the female were
conspicuous, and from the middle downwards those of the male.
Lefort had the general characteristics of each sex. The relative
proportion of the trunk and extremities, that of the shoulders and
pelvis, and the conformation and dimensions of the latter, were
those of the male; the chin had as good a beard, and the breasts
and extremities were covered with as abundant hair, as we
usually observe in fair young men of the same age. Yet there
were beautiful breasts with perfect areolae and nipples, the hands
and feet were small, and, like the other portions of the extremities,
most elegantly tapering. Its unforeseen departure from London
deprived me of the advantage of a second interview, but I fancy
that the voice, face, cranium, and mental character were a mixture
[Seite 312] of those of both sexes. The eyes certainly sparkled with desire.
Now had this been a man with imperfect organs, there might
indeed have been the characteristics of the female strongly
marked, but certainly not those of the male; and vice versa:
nor would the eyes in either case have expressed the warmth of
passion. On this account I am disposed to believe it in posses-
sion of at least one testis and one ovarium. The best judges in
Paris pronounce it a woman; the best in London, a man. With
respect to the genitals I own myself to have felt disinclined to
examine them at a first interview, but understand there was a
clitoris some millemetres in length – with an imperforate gland,
and an urethra running along it inferiorly (a structure perhaps
unknown in monstrous formation of simply female organs), and
opening underneath by five small holes. A passage existed at
the foot of the clitoris into which a catheter passed, but which
afforded no urine. The catheter introduced into it might be di-
rected downwards behind a membrane that united the labia below
– where the opening of the vagina is commonly found, and would
probably be divided with advantage, as the menses come through
this passage. In fact both they and the urine pass through
it and the five holes of the canal that is under the clitoris, and
the urine is reported to come through both, although the catheter
could bring none and neither passed into the bladder nor ex-
cited a desire to make water, if introduced into the lower canal.
Whence there is probability in the conjecture that the urethra
communicates with this passage within, by similar openings to
those observed externally in its lower part.

Lefort has been seen to menstruate, and those who have not
inspected the pudenda when visiting it at this period, have de-
clared the countenance to be pale and languid as in a menstru-
ating woman. It boasts of having menstruated ever since eight
years of age, of having desires for each sex, and of being able
fully to enjoy both. But a little exaggeration of this kind must
be expected. The attendant told me that it had kept a young
French girl some years. Whether seminal discharge takes place,
[Seite 313] is doubtful, as the communication between the testes (if there
are any) and urethra may be deficient in some point. That it
can derive any pleasure from sleeping with a male, except in the
general contact, is impossible. On the contrary, the membrane
that unites the labia must prevent coition and render every ap-
proach of the male organ extremely painful. No wonder, there-
fore, that, though its habits are feminine, (it does needle-work)
perhaps in some measure from confinement, it has, morally in-
deed! chosen a girl for its associate. Independently, however,
of these circumstances, I do not suppose that Lefort’s beard
and disgusting hairy breasts and limbs would easily procure a
cavalier servente.

SECT. XXXVI.
OF THE GENITAL FUNCTION IN MAN.

[Seite 314]

509. The genital fluid is produced in the two testi-
cles, which hang in the scrotum, by their spermatic
chords,
through a ring called abdominal, or through,
more properly, a fissure in the tendon of the external
oblique muscle of the abdomen. (A) Besides abundant
lymphatics, three orders of vessels are found in the
testes. –

The spermatic artery, which is, in proportion to the
fineness of its caliber, the longest artery, by far, in the
system, and usually conveys blood to the testicle im-
mediately from the aorta.

The ductus deferens, which carries to the vesiculae se-
minales the semen separated from the arterial blood.

The pampiniform plexus of veins, which return to the
cava or renal vein the blood remaining after secre-
tion. (B)

510. The testes are not always suspended in the
scrotum. In the very young male foetus, they are
placed in an extremely different situation, the nature
and successive changes of which were first accurately
investigated by Haller,* but have since been variously
stated; and the causes of this change of situation have
given rise to numerous controversies. I shall derive
[Seite 315] my account of this subject from the natural appear-
ances which I have preserved in a great number of
small embryos, dissected by me with this view.

511. On opening the lower part of the abdomen of a
young foetus, there appears in each groin, at the ring
of the oblique muscles, a very small opening in the
peritonaeum, leading downwards to a narrow passage
which perforates the ring and runs to a peculiar sac
that is extended beyond the abdominal cavity towards
the scrotum, is interwoven with cellular fibres, and
destined for the future reception of the testicle.

512. At the posterior margin of this abdominal open-
ing, there is sent off another process of peritonaeum,
running upwards, and appearing, in the young foetus,
as little more than a longitudinal fold, from the base
of which arises a small cylinder, or rather an inverted
cone, which terminates above in a globular sac, con-
taining the testis and epididymis, so that the testis, at
first sight, resembles a small berry resting on its stalk,
and appears hanging, like the liver or spleen, into the
abdomen. (399)

513. The vessels which afterwards constitute the
spermatic chord, are seen running behind the very de-
licate and pellucid peritonaeum; the spermatic artery
and vein descending along the sides of the spine, and
the vas deferens passing inwards in the loose cellular
substance behind the peritonaeum towards the neck of
the bladder. They enter the testis in the fold of peri-
tonaeum just mentioned.

514. After about the middle period of pregnancy,
the testis gradually descends and approaches the
narrow passage before spoken of (511), (the fold of
peritonaeum and the cylinder becoming at the same
[Seite 316] time bent down) until it lies directly over the opening
of the passage.

515. The testis being now ready for descent, the
opening which was hitherto small, becomes dilated, so
as to allow the organ to pass the abdominal ring and
passage and to descend into the bulbous sac (511); after
this occurrence, the opening soon becomes strongly
closed and even grows together, leaving scarcely any
vestige of itself in infancy.

516. In proportion to the slowness with which the
testis proceeded towards the opening, does its transit
through the abdominal passage appear rapid, and, as
it were, instantaneous. It is common to find the testis
in mature foetuses either lying over the peritonaeal
opening, or, having passed this, resting in the groin;
but I have once only met with the right testis, in a twin
foetus, at the very time when it was adhering, and in a
manner strangled, in the middle of the passage, being
just about to enter the sac; in this instance, the left
testis had passed the abdominal canal and was already
in the sac, and the abdominal opening was perfectly
closed.

517. This remarkable passage of the testis from the
abdomen through the groin, is limited to no period, but
would seem to occur generally about the last month of
pregnancy; the testicles are found, however, not very
rarely in the abdomen or the upper portion of the groin
at birth. For they have always another part of their
course to finish, after leaving the abdomen, viz. to de-
scend, together with their sac, from the groin into the
scrotum.

518. Repeated observation demonstrates this to be
the true course of the testicles. To assign the powers
[Seite 317] and causes of its accomplishment is no easy matter.
For I am every day more convinced that neither of the
powers to which it is usually ascribed, viz. the action
of the cremaster or diaphragm, or the mere contractility
of the cellular membrane, interwoven with tendinous
fibres, which adheres to the cylindrical process of pe-
ritonaeum (512) and is called the Hunterian gubernacu-
lum,
is sufficient to explain so singular a movement,
and least of all to explain the transit of the testis
through the passage so often mentioned; but that the
whole affords, if any thing does, a striking illustration
of a vita propria, without the peculiar influence of
which, so remarkable and unique a course, similar to
no other function of the system, cannot even be ima-
gined. (C)

519. The coats of the testes, after their descent, are
conveniently divided into common and proper.

The common is the scrotum, consisting of the skin
having a very moderate substratum of fat and differing
from the rest of the integuments in this, – that it is con-
tinually changing its appearance, being sometimes lax
and pendulous, sometimes (especially during the vene-
real orgasm and the application of cold) constricted
and rigid, and, in the latter case, singularly marked by
rugae and furrows.

520. With respect to the coats proper to each testis,
the dartos lies immediately under the scrotum, and is
endowed with a peculiar and strong contractile power,
which deceived the celebrated Winslow, Haller, &c.
into the belief of the presence of muscularity. (D)

521. Next to this, with the intervention however of
much soft cellular substance, are found three orders of
[Seite 318] tunicae vaginales;* viz. an exterior, common to the testis
and spermatic chord, and to which the cremaster muscle
adheres by disjoined bundles of fibres; and two inte-
rior, one proper to the chord, and one to the testis;
the fundus of the latter of which usually adheres to the
common coat, but is internally moistened, like the pe-
ricardium, by a lubricating fluid. (E)

522. The origin of these coats, – the subject of so
much controversy, may, I think, be readily explained,
from the circumstances, already mentioned, attending
the descent of the testis.

The common coat arises from the descending bulbous
sac or peritonaeal process. (511)

The proper coat of the testis, from that production
of the peritonaeum which, ascending from the cylin-
der (512), originally invests the testis.

The coat proper to the chord, from that fold and short
cylinder of the peritonaeum in which the fold terminates
before it surrounds the testicle. (F)

523. To the body of the testis there adheres very
firmly, like the bark of a tree, a coat called albuginea,
through the combination of which with the internal part
of the vaginal coat, blood-vessels penetrate into the
pulpy substance of the testis. This pulpy substance
is entirely composed of innumerable vessels, about a
span in length§ and convoluted into lobules, both con-
[Seite 319] veying blood and secreting semen,* the latter of which
is carried, through the rete vasculosum of Haller and
the vasa efferentia of de Graaf, to the apices of the
cones of the epididymis.

524. The Epididymis, lying on the side of the testicle
and consisting of one vessel about thirty feet in length,
is smaller, and divided into about twenty glomerules or
cones at the part called its head,§ and is continued
into the vas deferens, at its lower part, which gradually
becomes thickerǁ and is denominated its tail.

525. Each vas deferens, ascending towards the neck
of the urinary bladder and converging towards the
other under the prostate gland, is then directed back-
wards and dilated into the vesiculae seminales, in such
a manner, that the common mouth both of the vesicles
and vasa deferentia opens into the urethra, behind the
caput gallinaginis.**

526. The vesiculae seminales, which adhere to the pos-
terior and inferior surface of the bladder, surrounded
by an abundance of fat, resemble two little intestines
winding in various directions and branching into nume-
rous blind appendices.

They consist of two coats, nearly similar to those of
the gall bladder: the one strong, and of the descrip-
tion usually termed nervous; the other interior, deli-
[Seite 320] cate, abounding in cells, and divided into compart-
ments by prominent ridges, like those found in the
cervix of the gall bladder.*

527. In these passages is slowly and sparingly se-
creted and contained after puberty, the semen, a very
extraordinary and important fluid, of a milky yellowish
colour, of a peculiar odour, of the same viscidity as
mucus, and of great specific gravity, of greater indeed
than any other fluid in the body.

528. Semen has also this peculiarity, first observed
by Lewis Hamme of Dantzic, in the year 1677,§ – of
being animated by an infinite number of small worms
visible by the microscope, of the kind denominated
infusoria, and of different figures in different genera of
animals. In man,ǁ these spermatic animalcules are oval
and have very fine tails: they are said to be found in
prolific semen only, so that they are in some degree an
adventitious criterion of its prolific maturity; I say
adventitious, because I hope, after so many weighty
arguments and observations,** there is no necessity
[Seite 321] at present to remark, that they have no fecundating
principle, and much less are the germs of future off-
spring. (G)

529. The genital fluid gradually collected in the
vesicles is retained for subsequent excretion, and by
its stay experiences changes nearly similar to those
of the bile in the gall bladder, – becoming more inspis-
sated and concentrated by the removal of its watery
portion.*

530. As the whole of the testis and spermatic chord
abounds in lymphatic vessels, which carry back to the
blood a fluid with a seminal impregnation and thus
facilitate the secretion of semen in the manner before
described (477); so the vesiculae seminales are like-
wise furnished with a similar set of vessels, which, by
absorbing the inert watery part, render the remaining
semen more powerful.

531. But I very much doubt whether the semen is
ever absorbed during health; still more that it ever
passes into the neighbouring veins; and most of all,
that by this absorption, if it does occur, unseasonable
venereal appetites are prevented, since, if we compare
the phenomena of animals, procreating at particular
periods, with the constitution of those which are cas-
trated, we must conclude that this absorption is rather
the cause of ungovernable and almost rabid lust.

[Seite 322]

532. I conceive that this end is accomplished in a
very different mode, by a circumstance which occurs,
as far as I have been able to discover, in no animal
but man, – by nocturnal pollutions, which I regard as a
natural* excretion intended to liberate the system
from the otherwise urgent superfluous semen, more or
less frequently, according to variety of temperament
and constitution.

533. The semen is never discharged pure but mixed
with the prostate fluid, which is very much of the ap-
pearance of the white of egg, and has acquired its
name from the organ by which it is produced, – an
organ of some size, of a singular and very compact
texture, lying between the vesiculae seminales and
bulb of the urethra, and commonly denominated pros-
tate gland.
The passages for the course of this fluid
are not well known, unless perhaps they communicate
with the sinus of the seminal caruncle, the middle of
the orifice of which opens into the urethra between
the two mouths (525) of the seminal vesicles.

534. The male urethra is the common outlet of three
different fluids, – the urine, semen, and prostate liquor,
It is lined with mucus which proceeds from numerous
sinuses dispersed along the canal.§ We find it sur-
rounded by a spongy texture, upon which lie two other
[Seite 323] spongy bodies* of much greater thickness, constituting
the greater part of the penis. The penis is terminated
anteriorly by the glans – a continuation of the spongy
texture, and usually covered by a delicate and very
moveable skin, which is destitute of fat, and, at the
corona of the glans, forms the preputium that moves
over the gland as the eyelids do over the eyeball. The
internal duplicature of the preputium, changing its
appearance, is reflected over the glans, like the albu-
ginea of the eye, and is beset at the corona with many
Littrian glands, similar to the Meibomian of the eye-
lids and secreting a peculiar smegma.

535. The virile organ, thus constructed, possesses
the power of erection, – of becoming swollen and stiff
and changing its situation, from the impetuous conges-
tion and effusion§ of blood in its corpora cavernosa
[Seite 324] either by corporeal or mental stimulus, and of detu-
mifying and collapsing after the return of the blood.* (I)

536. When in a flaccid state, it is considerably bent
at its origin from the neck of the bladder, and thus
perfectly adapted for the discharge of the urine,
but quite unfit for the emission of semen, because the
origin of the urethra then forms an acute angle with the
openings of the seminal vesicles.

537. When the penis swells from desire, the prostate
fluid generally flows first, and indeed is often dis-
charged pure, though rarely together with the urine:
its principal use is to be emitted with the semen, either
by its albuminous lubricity correcting the viscidity of
the former and promoting its emission, or contributing
something peculiar to generation.

538. The emission of semen is excited by its abun-
dance in the vesicles and by sexual instinct: it is
effected by the violent tentigo which prevents the course
of the urine and, as it were, throws the way open for
the semen; by a kind of spasmodic contraction of the
vesiculae seminales; by a convulsion of the levatores
ani§ and of the acceleratores urinae; and by a short
and less violent succussion of the whole system, almost
[Seite 325] of an epileptic nature and followed by great depres-
sion of strength.* (L)


NOTES.

(A) Instances of more than two testes are extremely rare.
Three, four, and even five, are said to have existed, and several
authors declare that they themselves have seen three in individuals
many of whose families were equally well provided. Unless
such cases are related by an experienced medical man from his
own observation, they deserve no credit, and even then must be
regarded with suspicion, if anatomical examination has not
proved the additional bodies to be analogous to testes no less in
structure than in form and situation. The late eccentric
Dr. Mounsey, who ordered that his body should either be dis-
sected by one of his friends or thrown into the Thames, was
found to have in his scrotum a small steatom, which during life
might have given the appearance of three testes.

The writers of such wonderful cases completely disagree in
their account of the powers of these triorchides, tetrorchides,
and pentorchides, some asserting them to be prodigious, others
greatly below those of ordinary men.

One testis is commonly larger than the other, and, the right
spermatic chord being for the most part shorter than the left,
the right testis is generally the higher.

(B) The original situation of the testes accounts for the
circumstance of their blood vessels arising from the loins, as
Mr. Hunter remarked; for parts generally derive their vessels
[Seite 326] from the nearest source. The same applies to their nerves.
Hence too the right spermatic artery frequently springs from the
right renal as being nearer than the aorta, and the left spermatic
vein frequently pours its blood into the left renal as being nearer
than the inferior vena cava.

The original situation of the testes accounts also for the cir-
cumstance of the vas deferens arising from the lower part of the
epididymis and bending upwards; in the foetus this is not the
case, but it is the necessary consequence of the subsequent
change in the situation of the testes.*

C. The descent of the testes into the scrotum must, I appre-
hend, be owing to the growth of their nerves and vessels, and
to the direction afforded by the contraction of the gubernaculum;
the growth of the former, and therefore the whole process, is
accounted for in the minds of some by the contraction of the
latter. Mr. Hunter’s original account of the gubernaculum
may not be unacceptable. ‘“At this time of life, the testis is
connected in a very particular manner with the parietes of the
abdomen, at that place where in adult bodies, the spermatic
vessels pass out, and likewise with the scrotum. This con-
nection is by means of a substance which runs down from the
lower end of the testis to the scrotum, and which at present I
shall call the ligament or gubernaculum testis, because it con-
nects the testis with the scrotum, and seems to direct its course
through the rings of the abdominal muscles. It is of a pyra-
midal form; its large bulbous head is upwards, and fixed to the
lower end of the testis and epididymis, and its lower and slender
extremity is lost in the cellular membrane of the scrotum. The
upper part of this ligament is within the abdomen, before the
psoas, reaching from the testis to the groin, or to where the
testicle is to pass out of the abdomen; whence the ligament runs
[Seite 327] down into the scrotum, precisely in the same manner as the sper-
matic vessels pass down in adult bodies, and is there lost. That
part of the ligamentum testis, which is within the abdomen, is
covered by the peritonaeum all round, except at its posterior
part, which is contiguous to the psoas, and connected with it by
the reflected peritonaeum and by the cellular membrane. It is
hard to say what is the structure or composition of this liga-
ment: it is certainly vascular and fibrous, and the fibres run in
the direction of the ligament itself, which is covered by the fibres
of the cremaster or musculus testis, placed immediately behind
the peritonaeum. This circumstance is not easily ascertained in
the human subject; but is very evident in others, more espe-
cially in those whose testicles remain in the cavity of the abdo-
men after the animal is full grown.”’*

(D) We know that the skin of every part relaxes by heat and
contracts by cold, although it be not muscular: in the cold fit of
an ague, it is constricted throughout so forcibly as to have ac-
quired, during this state, the appellation of Cutis Anserina. The
scrotum, being much more lax than any other portion of the
skin, experiences these effects to the greatest extent. What is
termed dartos is merely thick cellular membrane.

(E) Another coat, exterior to the rest, is described by M. Roux,
and termed Envelope fibreuse. It is an elongated sac, large be-
low to contain the testis and epididymis, and narrow above, afford-
ing a sheath to the chord. It vanishes among the cellular mem-
brane of the ring. M. Roux considers this coat as having been
known to Haller, from the following passage in Haller’s account
of the testicle. ‘“Ita fit ut interiores cavae duae sunt; superior
vasculis spermaticis circumjecta; inferior testi propria.”’ But
Haller continues thus, ‘“Ita saepe se habet, ut etiam aquae vis aut
in partem testi propriam solam, intacta parte vasculosi funiculi,
aut in istam solam, intacta testis vagina, effundatur, neque flatus
impulsus de ea vaginali ad istam commeet.’ He appears there-
[Seite 328] fore to describe merely the tunica vaginalis of the chord and
testis.

(F) The cremaster deserves a little attention. This muscle
arises from the superior anterior spinous process of the ileum,
from the transversalis abdominis, the internal surface of the Fal-
lopian ligament and neighbouring parts, and, passing through
the ring, spreads upon the chord, vanishing upon the beginning
of the testicle. Its office is evidently to support the testicle, and to
draw it upwards against the groin during procreation. In those
animals whose testes, instead of hanging in the scrotum, lie in
the perinaeum, in the groin, or in the abdomen, this muscle
is, as might be expected, much less considerable.

It may here be mentioned that the human testes do not
always descend into the scrotum, but occasionally remain, one
or both, in the groin or abdomen. Individuals so circumstanced
were called κρυψόρχιδες or testicondi by the ancients. A ridgil
is a bull in which one only has descended. In these instances
the generative powers are not impaired; a testicle which has not
descended is prevented by the pressure of the neighbouring parts
from fully evolving itself, but such persons, it is certain, ‘“mili-
tant non sine gloria.
”’

The generative powers indeed are not impaired by the removal
of one testis: the Hottentots have been said frequently to de-
prive their sons of one on arriving at eight years of age,* from
the belief that monorchs are swift runners. We read in Varro,
that if a bull is admitted to a cow immediately after both testes
are removed, impregnation takes place, – ‘“Exemptis testiculis,
si statim admiseris, concipere (vaccas).”’ This at least is cer-
tain, that some men have perfectly performed the act of copu-
lation, though unfruitfully, after castration. Many such accounts
[Seite 329] are suspicious, but in a case mentioned by Mr. Astley Cooper in
his surgical lectures as perfectly unquestionable, the complete
power of coition positively remained some time after the removal
of both organs by that surgeon, and gradually diminished.

The notion that each testicle, or each ovarium, is destined for
the procreation of but one sex, is too nonsensical.

(G) Lewis Hamme, a young German, discovered the seminal
animalcules, and shewed them to Leeuwenhoeck; and the saga-
cious Dutchman, catching eagerly at the discovery, published an
account of them illustrated by plates. Hartzoeker, ambitious of
the honor of the discovery, wrote upon the subject the following
year, and asserted that he had seen the animalcules three years
before they were observed by Hamme. The subject, being the
very summit of filthiness, excited the earnest attention of all Eu-
rope. Physiologists, Naturalists, Popish Priests, Painters, Opti-
cians, and Booksellers, all eagerly joined in the pursuit of the
seminal animalcules, and the lascivious Charles the Second of
England commanded them to be presented to him swimming
and frisking in their native fluid. Some of the curious could not
find them. Others not only found them, but ascertained their
length was 3/100000 of an inch, their bulk such as to admit the
existence of 216,000 in a sphere whose diameter was the breadth
of a hair, and their rate of travelling nine inches in an hour.
They saw them too in the semen of all animals, and, what is
remarkable, of nearly the same size and shape in the semen
of the largest and of the smallest, – in the semen of the
sprat and of the whale; they could distinguish the male from
the female; in the semen of a ram, they beheld them moving
forwards in a troop with great gravity like a flock of sheep; and
in the human semen, Dalenpatius actually saw one indignantly
burst its wormy skin and issue forth a perfectly formed human
being. The little creatures would swim in shoals towards a given
point, turn back, separate, meet again, move on singly, jump
out, and dive in again, spin round and perform various other
feats, proving themselves, if not the most delicate, at least the
drollest, beings that ever engaged the attention of philosophers.
[Seite 330] Their strength of constitution being an important object of en-
quiry, they gave proofs of their vigour not only by surviving
their rough passage through the urethra, three, four, and seven
days, but by impregnating a female at the end of this time, and,
on being removed from her, by impregnating even a second.
Sure never was so much folly and bestiality before committed
under the name of philosophy.

Abr. Kauw Boerhaave, Maupertuis, Lieutaud, Ledermuller,
Monro Secundus, Nicolas, Haller, and indeed nearly all the phi-
losophers of Europe, were satisfied of the existence of the animal-
cules. Buffon and his followers, prejudiced in favour of an hypo-
thesis, although they did not deny that the semen contained
innumerable rapidly moving particles, contended that these
were not animalcules but organic particles, and Linnaeus imagined
them to be inert molecules thrown into agitation by the warmth
of the fluid. Their reality, however, might be regarded as esta-
blished. But finally to determine the question, and accurately
to ascertain every circumstance relating to them, the celebrated
Spallanzani began a long course of observations and experiments
about the middle of the last century, unbiassed in favour of any
opinion, and endeavouring to forget entirely all that had been
written upon the subject. The human semen he procured from
bodies immediately after death, and that of animals either after
death or during life.

He found in the former, innumerable animalcules with an
oval body and a tail or appendix tapering to a point. This ap-
pendix by moving from side to side propelled them forwards.
They were in constant motion in every direction. In about
twenty-three minutes their movements became more languid,
and in two or three hours they generally died, sinking to the
bottom of the fluid, with their appendices extended. The dura-
tion of their life, however, depended much upon the tempera-
ture of the weather; at 2 below 0 (Reaumur) they died in 3/4 of
an hour; while at 7° they lived 2 hours; and at 12 1/2, 3 hours
and three quarters. If the cold was not too intense, they
recovered upon the temperature being raised; when only 3 or
[Seite 331] 4 below 0, they recovered after a lethargy of fourteen hours and
upwards: and, according to the less intensity of the cold, they
might be made to pass from the torpid to the active state more
frequently. They were destroyed by river, ice, snow, and rain
– water; by sulphur, tobacco, camphor, and electricity. Even
the air was injurious to them; – in close vessels, their life was
prolonged to some days, and their movements were not constant
and hurried. They were of various sizes, and perfectly distinct
from all species of animalcules found in vegetable infusions, &c.
The seminal animalcules of different kinds of animals had gene-
rally each some peculiarity. In short, Spallanzani completely
confirmed the principal observations of Leeuwenhoeck, and satis-
factorily explained the sources of the inaccuracies of other
enquirers.*

Although these beings are most numerous in the semen, he
detected them occasionally in other fluids; – in the mesenteric
blood of female frogs and salamanders, and in the blood of a
tadpole and a calf.

It were to be wished that another Spallanzani would prose-
cute these enquiries.

According to Vauquelin’s analysis of the semen, 100 parts
contain,

Of Water 9. 0
Mucilage 6
Phosphate of lime 3
Soda 1

In some days it putrefies and becomes covered with the byssus
septica.

[Seite 332]

(H) Mr. Hunter’s arguments are the following. 1. ‘“The
semen, first discharged from the living body, is of a blueish
white colour, in consistence like cream, and similar to what is
found in the vasa deferentia after death; while that which fol-
lows is somewhat like the common mucus of the nose, but less
viscid. The semen becomes more fluid upon exposure to the
air, particularly that first thrown out; which is the very reverse
of what happens to secretions in general. The smell of the
semen is mawkish and unpleasant, exactly resembling that of
the farina of a Spanish chesnut; and to the taste, though at first
insipid, it has so much pungency, as, after some little time, to
stimulate and excite a degree of heat in the mouth. But the
fluid contained in these vesiculae in a dead body, is of a brownish
colour, and often varies in consistence in different parts of the
bag, as if not well mixed. Its smell does not resemble that of
the semen, neither does it become more fluid by being exposed
to the air.”’ On opening two men immediately after death, the
contents of the vesiculae were of a lighter colour than he usually
found them in persons who had been some time dead, and in one
of the instances so fluid as to run out upon cutting the vesiculae,
but they were similar to the semen neither in colour nor smell.
An examination of the vesiculae of the horse, boar, rat, beaver,
and guinea-pig, afforded the same results. In the last animal,
the contents near the fundus of the vesiculae were viscid, and
gradually firmer, till, near the opening into the urethra, they
were as solid as common cheese, and no such substance could
be detected in the vagina of the female after her union with the
male. 2. During lasciviousness, the testicles swell, and they
become painful, if the semen is not discharged; in coition, it
may be added, they are drawn forcibly by the cremaster against
the pubes, as if to assist the discharge of their contents at the
period of emission. 3. In the old and debilitated, the vesiculae
are as full as in the young and vigorous. 4. Nay, in four men
who had each lost a testicle, the vesicula on one side was equally
full as on the other, although they had survived the operation a
[Seite 333] considerable length of time. The same was discovered in two
cases, where, by mal-formation, one testicle had no commu-
nication with the corresponding vesicle. In the gelding and the
stallion their contents are similar and nearly equal in quantity.
The vas deferens has no communication in some animals with
the vesiculae, and in others, as the horse, where a communi-
cation does exist, the common duct is not of sufficient length to
permit the regurgitation of the semen into the vesiculae. 4. Some
animals, especially among the carnivora, have no vesiculae semi-
nales, yet in their copulation they differ not from those which
have. M. Richerand indeed asserts, that animals destitute of
these organs are longer in coition than others, from having no
reservoir for an accumulation of semen.* But he is mistaken.
For on inspecting Cuvier’s account of animals without and with
vesiculae, no connection whatever appears between their presence
or absence and the length of copulation.

In opposition to these arguments it is urged, that a fluid
gently propelled along the human vas deferens, does not pass
into the urethra, but regurgitates into the vesicula. But, grant-
ing this true, we have no proof that the secretion of the testes
leaves the vasa deferentia except during emission, when this regur-
gitation is impossible. It may also be contended that, in cases
of seminal weakness, the act of straining at the water-closet
often instantly discharges from the urethra, without the least
sensation, a large quantity of a fluid, which patients, who are
of course unprejudiced in favour of any opinion, declare to be
exactly similar, in colour, consistence, and odour, to that of a
nocturnal emission. The compression cannot squeeze this fluid
from the testes. If a partisan of Mr. Hunter should say that
the extremities of the vasa deferentia afford it, we may reply to
him that Mr. Hunter found them full of the same kind of fluid
as the vesiculae.

[Seite 334]

I believe, however, that we are unacquainted with the pure
secretion of the testes, and that far the greatest portion of an
emission is secreted by the vesiculae seminales and prostate gland;
and that therefore relaxed persons may, by forcing down, occasion
a discharge apparently identical with an emission, though not
containing a particle of matter furnished by the testes. The fact,
already mentioned, of emission occurring for a long period after
the removal of both testes, – till the removal had much deranged
the whole genital system, forcibly corroborates this idea. The dif-
ference discovered by Mr. Hunter between the fluid found in the
human vesiculae seminales after death and that of an emission, is
nothing more than might be expected if we were certain that
they were the same,* and as the matter squeezed out in sexual
debility exactly resembles that of a regular emission, this fact
is fatal to Mr. Hunter’s opinion, in regard to man, unless we
relinquish the notion of the fluid of human emission being chiefly
true semen from the testes. In different species of brutes the
fluid of emission may be furnished in different proportions from
the testes, vesiculae, and prostate, and the effects of pressure and
seminal debility in them are unknown.

(1) Accumulation of blood it is supposed may be produced in
three ways. 1. By a mechanical impediment to its return: but
there is no reason whatever to ascribe ordinary erection to
compression. 2. By an increased flow of blood to a part, so
that the vessels receive it faster than they convey it away. Here
the vessels of the part itself in which the accumulation exists,
are said by some to act more violently than usual; by others,
the neighbouring larger vessels which supply these: their fre-
quency of action, however, is not increased, but always remains
correspondent with that of the heart. Were the vessels of the part
itself to act more violently than usual, that is to say, to contract
to a smaller and relax to a greater dimension than usual, (though
an ordinary alternate contraction and relaxation is hypothetical)
[Seite 335] more blood would indeed subsist in them during their relaxation,
but less than usual would subsist in them during their contraction,
and there could be no accumulation, no inflammation. If the neigh-
bouring large vessels act more violently than usual, (though their
ordinary alternate contraction and relaxation are also hypothetical)
they may be conceived to produce an accumulation of blood and
a distention of the smaller vessels. 3. If the vessels of any part
become dilated and do not contract in proportion, this circum-
stance will be sufficient to produce an accumulation, without any
necessity for supposing an increased action of the neighbouring
larger vessels. This explains inflammation: and in Bichat’s
Anatomie Descriptive, this explanation is given of erection. The
corpora cavernosa which always contain florid blood, spon-
taneously dilate, and accumulation ensues. For this purpose it
is not necessary that they should be muscular, but Mr. Hunter
asserts their muscularity: in a horse he found them muscular to
the eye, and they contracted upon being stimulated.

The heart, however, as in all cases of what is called increased
determination of blood, lends its powerful aid by acting with
augmented force.

As to the final cause of erection, the organ, by acquiring
increased bulk, firmness, and sensibility, becomes adapted for
affording and experiencing to the utmost extent the effects of
friction both as exciting pleasure and as stimulating the secreting
vessels; the increased length and narrowness of the urethra ren-
der the emission more forcible.*

(K) If Gall is right in placing the seat of sexual desire in the
head, this kind of erection may be explained by supposing the
irritation, arising in the cerebellum from the great accumulation
of its blood, to produce a correspondent irritation in the organs
[Seite 336] of generation: thus the epileptic paroxysm is not unfrequently ac-
companied by an emission. Nocturnal emissions occur most
frequently after a person has been long in bed and supine, – the
cerebellum the lowest part of the encephalon, if the occiput is,
as usually, raised by a pillow. They may, however, be explained
by the urine accumulating in the bladder during the continuance
of repose and stimulating the generative parts connected with
this receptacle the more readily in the supine posture, and this
view is countenanced by the large quantity of urine generally
made on waking after nature has been thus relieving the chaste
unmarried man.

(L) The discharge of semen resembles the discharge of fluids
from all glands. It is excited by the abundance of the fluid, by
mental stimulus, or by mechanical irritation of the extremity of
the excretory duct, for in such a point of view must be regarded
the friction of the glans penis in copulation. The fluid is accu-
mulated in the bulb of the urethra, since it must be accumulated
somewhere to be emitted so copiously, and no other use can be
assigned to the bulb; and if the vesiculae do not receive it, no
other part but the bulb can; besides, it is upon the bulb
that the muscular contraction of the venereal paroxysm first
acts. ‘“The semen acting as a stimulus to the cavity of the bulb
of the urethra, the muscles of that part of the canal are thrown
into action, the fibres nearest the bladder probably act first, and
those more forward in quick succession, and the semen is pro-
jected with some force. The blood in the bulb of the urethra
is by the same action squeezed forward, but requiring a greater
impulse to propel it, is rather later than the semen, on which it
presses from behind; the corpus spongiosum being full of blood,
acts almost as quick as undulation, in which it is assisted by the
corresponding constriction of the urethra, and the semen is hur-
ried along with a considerable velocity.”’*

(M) Zeno’s practice was conformable to his principles. He
[Seite 337] is recorded to have embraced his wife but once in his life, and
then out of mere politeness.

Zenobia, the celebrated Queen of Palmyra and the East, was
as extraordinary a wife. She never admitted her husband’s em-
braces but for the sake of posterity, and, if her wishes were baffled,
she reiterated the experiment in the ensuing month.*

Epicurus, Democritus, &c. were nearly of the same opinion
with Zeno, and the Athletae, that their strength might be un-
impaired, never married. The Rabbies, in their anxiety to
preserve their nation, are said to have ordered, with the view of
preventing the loss of vigour, that a peasant should indulge but
once a week, a merchant but once a month, a sailor but twice a
year, and a studious man but once in two years.

SECT. XXXVII.
OF THE GENITAL FUNCTION OF WOMAN IN GENERAL.

[Seite 338]

539. As the male organs are fitted for affording, so
the female organs are fitted for receiving, and are cor-
respondently opposite to the former. In some parts,
the organs of each sex are very analogous to each
other in structure. Thus the clitoris, lying under the
pubes in the superior commissure of the labia, agrees
in many respects with the penis of the male, although
distinct from the urethra and imperforate and extremely
small in well-formed women. It is recorded to have
been, in some adult females, of as comparatively large
size as we stated it usually to be in the foetus, (492)
and these instances have probably given rise to most of
the idle stories of hermaphrodites.* Like the penis, it
has its corpora cavernosa, is capable of erection,
is covered with a prepuce, and secretes a smegma not
dissimilar from the Littrian. (525)

[Seite 339]

540. From the clitoris the nympha descend, also
occasionally of great size,* the source of other idle
tales, and, like the clitoris, possessing a high degree
of sensibility. They appear in some measure to direct
the stream of urine, because the opening of the urethra,
which is very short in females, and frequently ciliated,
as it were, with small papillary folds, lies under their
commencement.

541. Under the termination of the urethra lies the
opening of the vagina, surrounded by various kinds of
cryptae, v.c. the lacunae urethericae of De Graaf,§ and
the orifices of the prostates, as they are improperly
termed, of Casp. Bartholin,ǁ which secrete an unctuous
mucus.**

[Seite 340]

542. Across the opening; of the vagina, the Hymen*
is extended, – a membrane generally circular, found,
as far as I know, in the human subject alone, and of
no physical use hitherto discovered.

The remains of the lacerated hymen become the
caruncula myrtiformes, which are of no regular number,
and are infallible signs of the loss of virginity. (B)

543. The vagina, ascending between the urinary
bladder and rectum, consists of a very vascular cel-
lular parenchyma, is surrounded inferiorly by the con-
strictor cunni,
and lined internally with a very soft
coat, which is marked by two columns of rugae, – an
interior and posterior,§ pouring forth a mucus into its
cavity.

544. Upon the superior part of the vagina, rests the
uterus, suspended on either side by its broad liga-
ments. Its cylindrical cervixǁ is embraced by the
vagina, and perforated by a narrow canal, which, like
the vagina, is marked by rugae denominated the arbor
vitae, and is generally lined with a viscid mucus at
each extremity, but particularly at the superior.

545. The substance of the uterus is peculiar, – a very
dense and compact parenchyma** abounding in blood-
[Seite 341] vessels, which run in a curious serpentine direction*
and are destitute of valves. It has also a supply of
lymphatics, and a great number of nerves, whence
its remarkable sympathy with other parts.

546. The uterus is covered externally with perito-
naeum; its internal cavity is small, and lined, espe-
cially at the fundus, with a soft and very delicate
spongy membrane, which is composed, according to
some, (92) of colourless arteries and veins, (92) and,§
according to others, of lymphatics.ǁ

547. With respect to its muscularity, asserted by
some** and denied by others,†† I may remark that I
have never yet discovered a true muscular fibre in any
human uterus which I have ever dissected, whether
impregnated or unimpregnated, recent or prepared;
but it must be allowed, that the fibres, termed by some
muscular, have qualities very different from any others
observable in the system. I am daily more convinced
that the uterus has no true irritability, (301) but a vita
propria, (42) correspondent with the peculiar motions
and functions of the uterus, which are not referrible to
[Seite 342] any properties common to the similar parts, (39-41)
and which appeared to the ancient physicians and
philosophers so peculiar, that the uterus was by them
denominated an animal within an animal.* (C)

548. From the angles of the roof or fundus of the
uterus arise on each side the Fallopian tubes – narrow
and tortuous canals, running in the upper part of the
duplicature of the broad ligaments, similar in texture
to the vagina, but internally destitute of rugae, and lined
by a very soft and delicate spongy substance.

549. The extremity which opens into the abdomen is
not only larger than that which opens into the uterus,
but is surrounded by laciniated, and, as it were, digi-
tated fimbriae, singular and elegant in structure, which
are probably of great importance in conception, since
they appear to become turgid as well as the tubes them-
selves, during the venereal oestrum, and to embrace the
ovaria over which they lie.

550. The ovaria, or, as they were termed previously
to the time of Stenonis, the female testes, are com-
posed of a tough and almost tendinous covering, and a
dense and closely compacted cellular substance, which
contains in each ovarium about fifteen ovula, called
Graafian, viz. vesicles, or rather drops of albuminous
yellow serum, which coagulates like white of eggs, if
the recent ovarium is plunged into boiling water.

551. Such an albuminous drop appears to be what
the female contributes in the business of conception,
[Seite 343] and it is probable, that, during the adult state, these
drops become mature in succession, so that they one
by one force their way and finally burst the covering of
the ovarium and are received by the abdominal extre-
mity of the Fallopian tube.

552. Besides the albuminous drop which escapes
from the ovarium, another fluid, improperly styled fe-
male semen
by the ancients, is poured forth during the
venereal oestrum. Its nature, source, and quantity, are
enveloped in no less mystery than its office.*


NOTES.

(A) Blumenbach states it to be a prolongation of the labia on
the authority of Le Vaillant, but we are now certain that W.
ten Rhyne was correct, and that it is a prolongation of the
nymphae, which often hang five inches below the labia. The
same tribe of Hottentot women have another connate singularity
in the same quarter, common also to a variety of their sheep, and
the source of all the charms of the Hottentot Venus – a brilliant
example of denomination on the principle of lucus a non lucendo.
Her immense and tremulous buttocks displayed on dissection an
enormous accumulation of fat between the skin and muscles.

(B) Cuvier declares he has found the hymen in very many mam-
malia,§ overthrowing the doctrine, so strenuously maintained by
[Seite 344] Haller, of its existence for moral purposes. And, were it con-
tined to the human female, the various size of its aperture and the
various firmness of the organs, must ever leave those in uncer-
tainty who can on their marriage indulge in sensual doubts. We
read in Hume that Henry the Eighth, who certainly had his
share of experience, boasted his discrimination; but in the east
the difficulty was in ancient times proverbial. The lover
of Italian literature who for the sake of great beauties is content
to bear with much that is objectionable, knows how exquisitely
natural is every description of Boccacio’s, and will recollect his
story of the daughter of the Sultan of Babylon: – ‘“Essa, che
con otto uomini forse diecemilia volte giaciuta era, allato a lui
(al Re del Garbo) si coricò per pulcella, e fecegliele credere,
che così fosse: e Reina con lui lietamente poi più tempo visse:
e perciò si disse: Bocca basciata non perde ventura, anzi rin-
nuova, come fa la luna.”’*

(C) The muscularity of the uterus is allowed by Malpighi,
Morgagni, Mery, Littre, Astrue, Ruysch, Monro, Vieussens,
Haller, &c.

Mr. Charles Bell has a paper in the fourth volume of the Me-
dical and Surgical Society, which it is necessary to quote freely,
in order to give an accurate description of the muscular structure
of this organ.

‘“The muscularity of the uterus is proved by direct ocular
demonstration of the fibres in dissection, by the thickness of the
fibres corresponding with their degree of contraction, by the
visible action of the human uterus during life, by the resemblance
of the laws of its contraction, (as felt and as perceived in its
consequences) to those which govern the contraction of other
hollow viscera, and lastly, by the vermicular and intestinal mo-
tions of the uterus, as seen in experiments upon brutes.”’

‘“The most curious and obviously useful part of the muscular
substance of the uterus has been overlooked; I mean the mus-
[Seite 345] cular layer of fibres which covers the upper segment of the
gravid uterus. The fibres arise from the round ligaments, and
regularly diverging, spread over the fundus until they unite and
form the outermost stratum of the muscular substance of the
uterus.”’

‘“The substance of the gravid uterus is powerfully and dis-
tinctly muscular; but the course of the fibres is here less easily
described than might be imagined. Towards the fundus the
circular fibres prevail; towards the orifice the longitudinal fibres
are most apparent; and, on the whole, the most general course
of the fibres is from the fundus towards the orifice. This preva-
lence of longitudinal fibres is undoubtedly a provision for dimi-
nishing the length of the uterus, and for drawing the fundus
towards the orifice. At the same time these longitudinal fibres
must dilate the orifice, and draw the lower part of the womb
over the head of the child.’

‘In making sections of the uterus while it retained its natural
muscular contraction, I have been much struck in observing how
entirely the blood vessels were closed and invisible, and how
open and distinct the mouths of the cut blood vessels became
when the same portions of the substance of the uterus were dis-
tended and relaxed.”’ ‘“A very principal effect of the muscular
action of the womb is the constringing of the numerous vessels
which supply the placenta, and which must be ruptured when the
placenta is separated from the womb.”’

‘“Upon inverting the uterus and brushing off the decidua, the
muscular structure is very distinctly seen. The inner surface of
the fundus consists of two sets of fibres, running in concentric
circles round the orifices of the Fallopian tubes. These circles at
their circumference unite and mingle, making an intricate tissue.
Ruysch, I am inclined to believe, saw the circular fibres of one
side only,* and not adverting to the circumstance of the Fallo-
pian tubes opening in the centre of these fibres, which would
[Seite 346] have proved their lateral position, he described the muscle as
seated in the centre of the fundus uteri. This structure of the
inner surface of the fundus of the uterus is still adapted to the
explanation of Ruysch, which was, that this produced contraction
and corrugation of the surface of the uterus, which the placenta
not partaking of, the cohesion of the surface was necessarily
broken.’

‘Further, I have observed a set of fibres of the inner surface
of the uterus which are not described. They commence at the
centre of the last described muscle, and having a course at first
in some degree vorticose, they descend in a broad irregular band
towards the orifice of the uterus. These fibres co-operating with
the external muscle of the uterus, and with the general mass of
fibres in the substance of it, must tend to draw down the fundus
and lower segment of the uterus over the child’s head.’

‘I have not succeeded in discovering circular fibres in the os
tincae corresponding in place and office with the sphincter of
other hollow viscera, and I am therefore inclined to believe, that,
in the relaxing and opening of the orifice of the uterus, the
change does not result from a relaxation of muscular fibres sur-
rounding the orifice. Indeed, it is not reasonable to conceive
that the contents of the uterus are to be retained during the nine
months of gestation by the action of a sphincter muscle. The
loosening of the orifice, and that softening and relaxation which
precede labour, are quite unlike the yielding of a muscular ring.”’

SECT. XXXVIII.
OF THE MENSTRUA.

[Seite 347]

553. An important, and indeed the most frequent,
function of the uterus, is to afford a menstrual fluid
during about thirty years, – a law imposed upon no
other species of animal:* – Woman, in the words of
Pliny, is the only menstruating animal. The females
of no nation, hitherto explored, are exempt from this
law, since it is among the requisites in the female sex
for the propagation of the species.

554. The commencement of this function usually
[Seite 348] occurs about the fifteenth year, preceded by symptoms
of plethora, by a sense of heaviness in the chest, and
of tension in the loins, by lassitude of the limbs, & c.
From the first of these symptoms, a reddish fluid gene-
rally flows from the genitals, becoming by degrees of
a more bloody colour, and at length completely so.
This has a peculiar odor, coagulates but imperfectly,
and differs also in other respects from blood. It con-
tinues to flow slowly for some days, and the unpleasant
symptoms above described in the mean time cease.

555. This red discharge returns alter this period
about every four weeks, and continues about six days,
during which time a healthy woman is supposed to
lose, perhaps, from five ounces to half a pound of
blood.

556. This action is usually discontinued during preg-
nancy or suckling. It entirely ceases after existing
about thirty years; and consequently, in our climate,
about the forty-fifth year of age.

557. By some, the vagina, by others, and with more
probability, the uterus, is considered the source of this
discharge. Instances of women menstruating although
pregnant or having the uterus imperforate or prolapsed,
do not favour the former opinion, but only prove the
extraordinary compensating powers of nature, who
employs new ways, when the usual ones are obstructed.
On the other hand, the dissection of many women who
have died during menstruation, has discovered the ca-
vity of the uterus bedewed with the catamenia.* I say
nothing of the à priori argument – that the purpose of
menstruation is probably to render the womb fit for
[Seite 349] pregnancy and for nourishing the foetus.* (A) On the
same account, the arteries rather than the veins appear
to be the source of the discharge.

558. The investigation of the causes of the periodical
return of this hemorrhage is so difficult, that we can
obtain nothing beyond probability, and shall not dare
to offer any thing merely conjectural.

The proximate cause is supposed to be a local§ ple-
thoric congestion, – an opinion with which the symp-
toms preceding menstruation, and the abundance and
nature of the uterine vessels, agree very well.

Among the remote causes may be enumerated the
erect posture peculiar to the human race, the peculiar
parenchyma of the uterus, and its vita propria.

It will be better to confess our ignorance of the cause
of its periodical return, than to indulge in vain hypo-
theses: for all the periodical phenomena of health and
[Seite 350] disease, which continue more than twenty-four hours,
have hitherto appeared among the mysteries of animal
nature.


NOTE.

I have known some women bear children before they had ever
menstruated and others after menstruation had entirely ceased.

Neither is the pleasure of coition requisite to impregnation,
for the mother of one of Napoleon’s generals, as well as of
other children, told a friend of mine ‘“Qu’elle n’avoit eu que les
douleurs d’enfanter,”’ and the late Dr. Heberden has the follow-
ing passage: – ‘“Duo mariti mihi narrarunt uxores suas in ve-
nerem fuisse frigidas, omni ejus cupiditate et voluptate carentes;
saepe tamen gravidas factas esse, et recte peperisse.”’*

SECT. XXXIX.
OF CONCEPTION AND PREGNANCY.

[Seite 351]

559. We now come to the functions for which the
genital organs are given us, – to conception and the
propagation of the species, in treating of which, we
shall first merely describe the phenomena that are ob-
served in that admirable and truly divine process, and
afterwards investigate the powers by which they are
produced.

560. In the first place, it is worthy of remark that
the human race, unlike most animals, does not copulate
at certain periods of the year,* but that with it every
season is equally favourable to the flame of love.

561. When a woman receives a man and both burn
with that animal instinct which is superior to all others
in universality and violence, the uterus, swelling I ima-
gine with a kind of inflammatory orgasm, and ani-
[Seite 352] mated by its vita propria (547), draws in, as it were,
the semen ejaculated by the male,* and appears to
pour forth a fluid of its own against it (552); the tubes
become rigid, and their fimbriae embrace the ovaria, in
one of which a ripe Graafian vesicle bursts like an ab-
scess, and its albuminous drop of fluid, being absorbed
by the abdominal opening of the tube, is conveyed to
the womb.

562. After the escape of this drop from the ovarium,
the lips of the wound are closed by an external cica-
trix, and the remaining vascular membrane is converted
into a corpus luteum. This is at first hollow, and full,
as appears to me, of a plastic lymph, which in progress
of time becomes a fleshy nucleus, surrounded by a
thick, remarkably vascular, cortex.§ (A)

563. After impregnation, the canal which runs along
the cervix of the uterus, is thoroughly closed, espe-
[Seite 353] cially towards its superior or internal orifice (544), so
that superfoetation, properly so called,* cannot natu-
rally take place. There are scarcely any constant and
infallible signs by which the woman herself can be
very certain of the changes that occur within during
conception.

564. The internal surface of the uterus becomes lined
with plastic, and, as it were, inflammatory, lymph (15),
which forms the tunica caduca or decidua of Hunter.
This is said to consist of two laminae, – the crassa in-
vesting the uterus except at the orifices of the tubes
and of the canal of the cervix,§ – and the caduca re-
flexa,
ǁ so denominated from being, after the ovum
begins to be formed and to take root in the decidua,
continued over the other parts of the ovum, just
[Seite 354] as the peritonaeum is continued over the abdominal
viscera.

565. The ovum* is produced before the embryo which
it is intended to contain, but scarcely begins to be
formed earlier than the end of the second week from
conception. Previously to this period, I very much
doubt whether any vestige of human conception has
ever been visible. (C)

566. This ovum consists, besides the external acces-
sary covering afforded by the caduca of Hunter, of two
proper velamenta or membranes.

Of an exterior – the chorion of the moderns, the
external surface of which is, from the first, nearly
covered with inexpressibly beautiful knotty flocculi;
whence it has been called the flocculent, leafy, or
mossy, chorion. By means of these flocculi, which are
the rudiments of the foetal portion of the future pla-
centa,
the ovum takes root, as it were, in the uterine
decidua. (564)

Of an interior – styled amnion, possessing no blood-
vessels (5), delicate, but remarkably tough.

567. These two proper membranes of the ovum differ
very much from each other in size the first week after
the formation of the ovum; the chorion appears a large
bladder, to which the amnion, like a much smaller
[Seite 355] bladder, adheres in that part only which nearly corres-
ponds with the centre of the external flocculent surface
of the chorion.

The remaining space between the chorion and amnion
is filled by a clear water, which may be called the liquor
chorii,
of doubtful origin and short duration.

For, since the amnion increases more rapidly than
the chorion and approximates to the latter even during
the first months after conception,* in proportion to its
approximation must this fluid necessarily be absorbed.

568. The internal membrane of the ovum is filled,
from its first formation (565) to the last moment of
pregnancy, with the liquor amnii, an aqueous fluid, of
a yellowish colour, nearly inodorous, of a bland and
scarcely saltish taste, commonly thought nutritious, and
compared to albumen, from which, however, more accu-
rate investigation proves it to differ considerably.

Its source is doubtful and cannot be referred to the
foetus or umbilical chord, because it exists in abortive
ova containing neither.

Its quantity is inversely as the size of the foetus.
Hence we may conjecture that its use is rather to de-
fend the foetus while nearly gelatinous and most liable
to suffer from external injuries, than to afford nourish-
ment. That the portion of fluid which occasionally,
although rarely, and therefore not naturally, enters the
[Seite 356] stomach of the foetus, is not destined to nourish it, is
evident from the nature of this fluid, and from the state
of the chylopoietic system of the foetus: to omit argu-
ments deduced from acephalous foetuses, &c.*

569. The embryo, which swims in this fluid, sus-
pended by the umbilical chord, like fruit by its stalk,
begins to be formed about the third week after con-
ception: at first it appears of rather a globular shape,
resembling a little bean or kidney, from which the ru-
diments of the extremities grow and the face is at
length formed, &c.

570. By nature, woman is uniparous, conceiving
but one foetus. Frequently, however, she produces
twins, the proportion of which to single births, Süss-
milch estimates as 1 to 70.‡‡ In these cases, each
[Seite 357] child has usually its own amnion, whereas there is a
common chorion.*

571. The medium of connection between the mother
and child, are the umbilical chord and the placenta into
which it is distributed.

572. The umbilical chord, which appears coeval with
the embryo, varies exceedingly in length and thickness,
in the place of its insertion into the placenta, in its va-
ricose knots, &c. It generally consists of three blood
vessels twisted spirally together, viz. a vein running to
the liver of the foetus, and two arteries arising from its
internal iliacs or hypogastrics. They are separated from
each other by cellular septa of various directions, and
are throughout narrowed internally by nodules or the
quasi-valves of Hoboken.

They are collected into a chord by means of a cel-
lular membrane, which is full of a singular very limpid
fluid called Whartonian, resembling gelatine in appear-
ance, and is surrounded externally by a continuation
of the amnion.

573. At the part of the chord which is united to the
foetus, there runs the urachus,§ which arises from the
fundus of the urinary bladder and lies between the two
umbilical arteries. In the human subject, it is pervious
[Seite 358] but for a very short distance, and, indeed, soon disap-
pears altogether. In other mammalia it leads to the
allantoid,* which is universally acknowledged to be
absent in the human foetus. For I think that the pro-
blematical vesicula umbilicalis, found in human ova be-
tween the chorion and amnion, is not analogous to the
allantoid but to the tunica erythroides that is seen in
the ova of some mammalia, and to the vitellary sac of
the incubated egg. It is found in healthy human ova,
the second or third month after conception, too fre-
quently and of too constant an appearance to be re-
garded as accidental, morbid, or monstrous.§

[Seite 359]

574. The blood-vessels of the chord pass to the pla-
centa,
of whose origin from the flocculent surface of
the chorion that is united to the decidua crassa, we
formerly spoke. Hence we discover how the substance
of the placenta is double, – the uterine portion derived
from the decidua and forming a spongy parenchyma,
the foetal arising from the umbilical vessels distributed
on the chorion. The increase of the ovum is irre-
gular, the smooth part of the chorion growing more
rapidly than the flocculent; consequently, the size of
the placenta bears a greater proportion to that of the
ovum, the shorter the period that has elapsed since
conception, and a smaller, as the period of labour
approaches.

As pregnancy advances, its texture becomes more
compact; furrowed and lobular on its uterine surface,
and smooth on the inner surface which is covered by
the amnion. It varies greatly in size, thickness, figure,
and situation, or place of attachment to the uterus;
generally it adheres to the fundus; it is destitute of
sensibility and true irritability.

575. Although all agree that the placenta is the chief
instrument in the nourishment of the foetus, the true
mode of its operation, and its mutual relation to the
uterus and foetus, have given rise to great controver-
sies in modern times. After all, the truth appears to
be this, – that no anastomosis exists between the blood
vessels of the uterus and of the chord, but that the
oxygenised blood which proceeds from the uterus to
the portion of the placenta that was originally the
decidua crassa, is absorbed by the extreme radicles of
the umbilical vein distributed upon the flocculent cho-
rion, and carried to the great venous trunk of the
[Seite 360] chord; while the carbonised blood returning from the
foetus, through the umbilical arteries, being poured in
the same manner into the substance of the placenta, is
absorbed by the venous radicles of the uterine portion
of the placenta, and returned to the uterus.

This account is supported by very careful but fruit-
less attempts to inject the umbilical by means of the
uterine vessels, and the uterine by means of the umbi-
lical; or to tinge the bones of the foetus with red, by
giving madder to the mother during pregnancy. It is
also confirmed by the difference observable between
the blood of the mother and foetus. (E)

576. During the progress of pregnancy, while the
foetus and secundines are increasing, the uterus of
course undergoes important changes, not only in size,
but in situation, figure, and especially in its texture,
which is considerably changed both with respect to its
blood-vessels and the intervening parenchyma, from
the constant and great congestion of fluids that occurs.

In proportion as the uterus increases, the blood-
vessels from being tortuous and narrow become more
straight* and capacious, and the veins, near the ter-
mination of pregnancy, acquire so great a bulk as
to have been taken for sinuses by some anatomists.

The parenchyma becomes gradually more thin and
lax, especially in the part nearest the ovum, so that
although the gravid uterus is very thick, particularly
at its fundus, and in a living and healthy woman is
turgid with blood and replete with vital energy, never-
[Seite 361] theless it is soft, and its general nature, (especially
after death, when, as Arantius long since remarked,
it almost appears lamellated if pregnancy was ad-
vanced,*) extremely different from the firm and com-
pact substance of the unimpregnated uterus.

577. The remaining important changes of the gravid
uterus, as well as those still more remarkable ones
which occur to the ovum and foetus, we shall briefly
relate in the order of the ten lunar months according
to which pregnancy is at present very conveniently
calculated.

578. As the uterus immediately after impregnation
always becomes turgid, (561) so, increasing from that
period in bulk and weight, it descends into the upper
part of the vagina, still retaining its former figure dur-
ing the first three months, except, that, perhaps, its
fundus becomes a little more convex and its anterior
portion somewhat recedes from the posterior, and that
its cavity, before extremely small and nearly triangular,
becoming expanded by the fluids of the ovum, accom-
modates itself to their subglobular form.

The ovum itself, which about the termination of the
first month is of the size of a pigeon’s egg and posesses
both deciduae separate from each other and the minute
amnion separate from the larger chorion, commonly
attains, near the end of the third month, the size of a
goose’s egg; the decidua reflexa then closely ap-
proaches to the crassa, and the amnion to the chorion;
[Seite 362] the former is filled with the fluid which bears its name
and defends from the pressure of the womb the tender
embryo that is now very small in proportion to it,
scarcely indeed equal to the size of a young mouse,
and hanging headlong and rather unsteadily.*

579. From the fourth month, the uterus becomes
more oval or subglobular, and, its neck gradually
softening, shortening, and almost disappearing or rather
distending laterally, it tends upwards and begins to
rise to the superior part of the pelvis. At the same
time the tubes ascend with the convex fundus of the
uterus, and are extended and elongated, but adhere to
the sides of this organ so firmly, that half of their
length only is separate from it, and, at first sight, they
appear to arise from the middle of it, – a circum-
stance which gave occasion to an erroneous opi-
nion of the enormous increase of its fundus. After
this period, the foetus acquires a size more propor-
tional to the capacity of the ovum, and becoming, at
the same time, conglobated together, acquires a more
fixed situation, which it preserves to the end of preg-
nancy; the head is inclined to the chest, and the back
bent and generally placed rather towards one side of
the mother.

580. In the middle of pregnancy, – at the end of the
fifth month, so much has the uterus increased, that its
fundus is nearly between the navel and pubes, and
pregnancy becomes externally evident. From this pe-
riod, the foetus by its motion is generally more dis-
tinctly perceptible to the mother: this circumstance,
however, occurs at no definite time.

[Seite 363]

581. The uterus and foetus continuing to increase
during the remaining five lunar months, the fundus of
the former reaches the umbilicus about the sixth month;
after the eighth, having risen higher, it approaches the
scrobiculus cordis. In the mean time, the cervix is
gradually obliterated, flattened, and attenuated.

582. In the tenth month, the uterus, overwhelmed, as
it were, with its own bulk, – being eleven inches in
length and nine or more in breadth, begins to subside.

Each decidua, but especially the reflexa adhering to
the chorion, having for many months been growing
thinner, now almost appears a net-work of short white
fibres.*

The larger diameter of the placenta is now nine
inches; its thickness one inch; its weight one pound
or upwards.

The length of the umbilical chord is generally eighteen
inches or more.

The weight of a common full grown foetus is usually
seven pounds; its length about twenty inches.

The quantity of the liquor amnii is too variable to be
defined; but when the foetus is strong, it seldom ex-
ceeds a pound.


NOTES.

[Seite 364]

(A) The important contents of this and the preceding para-
graph demand farther attention.

Several questions occur. 1. What is the state of the female
organs during the vehemence of desire? 2. How far does the
semen masculinum penetrate? 3. Do the Graafian vesicles burst
from the influence of the semen masculinum, or from mere
excitement, the semen impregnating only the contents of the
vesicles after their escape from the ovaria? 4. At what period do
the Graafian vesicles burst?

1. Mr. Cruikshank, on inspecting the genitals of a female
rabbit during heat, observed appearances nearly similar to those
described by Harvey, Graaf, Ruysch, Diembroeck, &c.* He
found them all prodigiously turgid with blood; the vagina was
absolutely of a dark mulberry colour, and on the ovaria were
prominent spots which injection proved to be vascular and which
were swollen Graafian vesicles; the contents of the vesicles,
however, remained transparent: the Fallopian tubes were also
nearly black, writhing in an extraordinary manner, having a
strong peristaltic motion, and embracing the ovaria with their
fimbriated extremity so closely as to lacerate on an attempt to
disengage them. These observations were all confirmed by
Mr. Saumarez. During copulation, this state of the organs
must be carried to the highest pitch of intensity.

2. Harvey could never detect semen in the uterus after copu-
lation.§ Nor De Graaf in the vagina.ǁ Verheyen found a large
quantity in the uterus of a cow, six hours after copulation.**
Galen always discovered it in the uterus of brutes after copu-
[Seite 365] lation.* Leeuwenhoeck, in the case of rabbits. Ruysch found
it not only in the uterus, but in the Fallopian tubes of two wo-
men killed in the act of adultery. Postellus, Riolan, Carpus,
and Cheselden also believed they found it in the uterus. Haller
once found it in the uterus of a sheep, forty-five minutes after
coition.§ Fallopius frequently found it in the tubes.ǁ Haller
very justly remarks that some of those who believed they saw
semen in the uterus, probably saw mucus only. He inclines,
however, with almost all physiologists, to the opinion that
the semen does enter the uterus. The length of the penis,
the force of emission, the peristaltic action of the vagina during
the heat of some brutes,** the existence of a bifid glans with two
orifices in the penis of the males of some species the females
of which have two ora uteri,†† are circumstances of no little
weight in favour of the opinion that the semen does pene-
trate at least into the uterus. Mr. Hunter, however, actually
saw it projected into the uterus of a bitch which he killed by
dividing the spinal marrow while united with the male.‡‡

Dr. Haighton, with the view of ascertaining whether it is
necessary to impregnation that the semen pass along the Fallo-
pian tubes, made a number of experiments on the effects of tying
and dividing them in rabbits at different periods relative to
[Seite 366] coition.* The peristaltic action of the tubes and their adhesion
to the ovaria during the venereal ardour, argue strongly in favour
of the semen being conveyed along them, because we can hardly
suppose these circumstances to begin to occur at this period for
the purpose of conveying the contents of the Graafian vesicle,
as this does not burst till a considerable time after copulation.
Dr. Haighton, indeed, says that these changes in the tubes
did not take place in his experiments till long (forty-eight hours)
after copulation, – till the ovaria were about to discharge into
them their vesicular fluids. In this he agrees with Bartholin,
De Graaf, Schurig, Deswig, and Lang, who maintained, like
him, that the semen, at least as far as examination went, does
not enter the tubes. But Mr. Cruikshank and Mr. Saumarez,
two of the latest experimenters, assert the contrary in the detail
of their experiments, and, as Haller remarks of the old parti-
sans, the negative experiments of the former cannot overturn
the positive testimony of the latter, – ‘“Eorum experimenta
negativa non possunt affirmantium fidem evertere:”’ Sbaragli,
[Seite 367] Verheyen, Hartman, and Duverney, could find no change in the
state of the tubes at any time, although their negative observa-
tions are completely overthrown by the positive observations of all
others who have enquired experimentally into the subject. Besides,
the great abundance of blood in the genital organs, during the sex-
ual ardour, must cause the tubes to enlarge and apply themselves
to the ovaria this, as Haller mentions upon the authority of Hart-
soeker, occurs even in the dead body by means of injection.

Dr. Haighton, however, to prevent the semen from passing along
the tubes, divided one of them in virgin rabbits, and, after the wound
was healed, admitted the animal to the male. The ovarium on this
side contained corpora lutea equally with the other, proving that
the Graafian vesicles had burst, although the semen could not pos-
sibly have reached the ovarium.* No foetus, notwithstanding, was
discoverable in any instance: on the other side (for in the rabbit
the uterus is double) foetuses were found equal in number to the
corpora lutea. Dr. Haighton concludes that impregnation may
take place without the advance of semen along the tubes. And
his conclusion is perfectly just, according to his test of impreg-
nation, – the escape of the contents of a Graafian vesicle. But I
apprehend this to be no more deserving the title of a test of
impregnation than the emission of the semen masculinum.
Impregnation is that change wrought by means of the male
semen in the contents of a Graafian vesicle, which enables them
to become a foetus. Now this was never effected when the tube
was divided: – although the presence of corpora lutea proved
vesicles to have burst, yet a foetus was in no one instance dis-
covered: in other words, the contents of the Graafian vesicles
[Seite 368] were in no one instance impregnated. Hence I conclude, with the
old physiologists before the time of Harvey, that the conveyance
of semen beyond the vagina, – where it may come in contact
with the contents of an ovarian vesicle, is absolutely requisite to
impregnation; and perhaps the state of the tubes during the heat
of some brutes (page 364), and the occasional growth of foetuses in
the tubes, abdomen, and in the ovaria themselves,* render it likely
that the semen passes even into the tubes. But Dr. Haighton’s
experiments were unnecessary for this conclusion, because patho-
logical observation proves sterility to be an invariable conse-
quence of complete obstruction in any point between the
os externum and ovaria, – in the Fallopian tubes, in the uterus,
or in the vagina.

When the obstruction in such cases is so far within as to allow
the deposition of the semen, the sterility disproves the notion of
Bartholin and Stenonis, – that this fluid operates by absorption.

[Seite 369]

3. Dr. Haighton imagines that the bursting of the vesicle
is the sympathetic effect of the semen in the vagina or uterus.*
Now although on the side where the tube was divided the
ovarium did discharge the contents of some vesicles, it is not
proved to have done this through the operation of the semen.
The venereal ardor alone was shewn in the observations of
Mr. Saumarez as well as in those of Mr. Cruikshank (and the
same has been remarked in the human female) to produce,
[Seite 370] among the other great changes of the sexual organs, the
enlargement of the vesicles. Nay we are certain that it will
occasion the rupture of the vesicle without any commerce with
the male. The hens of poultry lay eggs (incapable indeed of
being hatched), although separated from the cock, – a circum-
stance proving that in them the oestrum is sufficient to enlarge
and burst a vesicle, apply the tube to the ovarium, and occa-
sion it to convey away an ovum. Aristotle and Harvey relate
that many birds lay eggs from mere titillation; the latter proved
it experimentally in the thrush, in the sparrow, and in a favorite
parrot belonging to his wife. Blumenbach* is satisfied with the
accuracy of the accounts which he has read of corpora lutea in
virgins, and since he wrote we have been furnished with abun-
dant instances of their appearance in virgins not only of our
own kind but of quadrupeds. Sir Everard Home asserts that
the corpus luteum is not a formation that fills up the cavity of a
ruptured vesicle, but a substance in which the ovum is produced,
and consequently no proof of conception. However this may be,
the case remains the same; for he has repeatedly seen ovaria of
both human and quadruped virgins that had discharged ova.
Indeed he revives the old opinion of Kerekring, that ova are
continually growing to maturity in succession and discharged.
On this point I find it difficult in the present state of our know-
ledge to make up my mind, but I think it pretty evident that,
although the semen has no share in bursting the ovarium, the
high excitement of copulation contributes very considerably to
it, since the inferior degree of excitement which occurs during
the heat of brutes and in the lascivious states of the human
[Seite 371] virgin is sufficient frequently to effect the discharge of ova. It
is perhaps impossible otherwise to explain the fact that ova are
so commonly expelled from the ovaria and impregnated when-
ever a connection is arbitrarily or casually brought about. Hen
pigeons, if kept with males, lay not only at an earlier age, but
all the year round, instead of merely in the spring.

How the semen operates upon the ovarian secretion in fecun-
dating and transmitting the paternal peculiarities, is a mystery
impenetrably concealed from human curiosity.

4. The rupture of the ovarium has been said not to occur till
some time subsequent to coition. Mr. Cruikshank did not see
ova in the Fallopian tubes of rabbits, nor orifices in the corpora
lutea, till the third day from copulation,* nor ova in the uterus
till the fourth. Dr. Haighton never found any thing of a regular
form in the uterus before the sixth day.

(B) An instance of superfoetation of the description granted
by Blumenbach occurred to Mr. Blackaller of Weybridge. A
white woman of very loose character left her husband, and some
time afterwards returned pregnant to her parish and was delivered
in the workhouse of twins, ‘“one of which,”’ says Mr. Blackaller
in an account which he very handsomely sent me, ‘“was born
of a darker colour than I have usually observed the infants of
negroes in the West Indies; the hair quite black with the
woolly appearance usual to them, with nose flat and lips thick:”’
the second child had all the common appearances of white
children.

The uterus has been sometimes wanting, sometimes desti-
tute of anterior opening, and sometimes double,§ in which
last case we may imagine superfetation possible at any period
after the first conception, provided each uterus have a distinct
[Seite 372] orifice. It has frequently been removed after inversion, and
several lives have lately been saved by this operation.*

A dissection is described by Dr. Granville of a woman who had
borne eleven children, male and female, and who died soon after
being delivered of twins of both sexes. The right half only of
the uterus was found developed, the left extending scarcely half
an inch from the centre and shaped to a perfectly straight line: the
left tube and ovary did not exist. This proves, if the proof were
required, that one ovary is, like one testis, sufficient, not only for
procreation, but for the procreation of offspring of both sexes.
Dr. Granville thinks the case useful in proving also both that twins
and twins of different sexes may come from the same ovary, con-
trary to the opinion of all physiologists, he says, except Sir Eve-
rard Home. The common fact, however, of three or four chil-
dren being produced at a birth, sufficiently establishes the former
conclusion.

As each foetus, where there are more than one, may possess a
separate placenta and chorion, and may come into the world
solitarily, at some months distance perhaps from the other deli-
very, we see how easily practitioners may fancy a superfetation,
when there is simply an expulsion of twins, triplets, &c. at dif-
ferent periods.

(C) Mr. Bauer has detected the human ovum on the eighth
day from coition. It consisted of two membranes: – the external
open throughout its length, but with its edges turned inwards,
like shells of the genus voluta; the internal pointed at one end and
obtuse at the other, slightly contracted in the middle, and con-
taining, besides a slimy fluid, two globules that might be moved
by pressure but quickly resumed their situations and were pro-
bably the rudiments of the heart and brain.

(D) During 57 years, above 78,000 women have been deli-
[Seite 373] vered at the Dublin Lying-in-Hospital, and the proportion of
women producing twins or more is about 1 in 57.

The proportion of males to females, about 10 to 9.*

(E) Fourcroy is almost the only author who has examined
the blood of the foetus, and his observations, Berzelius re-
marks, ‘“seem to have been made by chance, and not to be de-
duced from any experiment;”’ ‘“credible authors have asserted
that the eye cannot distinguish between the arterial and venous
blood of the foetus.”’ Bichat could observe no difference in
the arterial and venous blood of the umbilical chords of several
guinea-pigs examined while the mother’s respiration was still
continuing after an opening had been made into the abdomen,
‘“– les deux sangs offroient une noirceur egale.”’§ So too in
regard to dogs.ǁ

The chick, nevertheless, in the egg, cut off from all intercourse
with the mother, requires its blood to be purified by the external
air: for if the shell is varnished, the chick dies; and if, during
the latter half of incubation, the shell is carefully opened, the
chorion, to use the language of Blumenbach, presents one of the
most splendid spectacles in the organic creation; the arteries are
seen carrying blood of a bright scarlet, and the veins of a livid
red.** The foetus of the kangaroo has no vascular connection with
the mother, being surrounded by a kind of jelly, and is supplied
with external air by tubes opening into the uterus from within,
for this express purpose.

SECT. XL.
OF THE NISUS FORMATIVUS.

[Seite 374]

583. Having simply described the phenomena of
conception and the changes which constant observa-
tion proves to occur both in the ovum and the con-
tained foetus during pregnancy, we now proceed to
those powers by which it appears that generation is
effected.

584. Even in our memory, some physiologists of
reputation have contented themselves with roundly
asserting that true generation never occurs, but that
the whole human race pre-existed in the genitals of
our first parents, in the shape of previously-formed
germs which become evolved in succession. Some of
these imagined the germs to be the spermatic animal-
cules of the male;* others imagined them to exist in
the ovaries of the mother.

[Seite 375]

585. This hypothesis of the successive evolution of
germs pre-formed from the creation, must, if carefully
examined, be rejected.* Not only is the superfluous
and useless creation, which is supposed, of innume-
rable germs never arriving at evolution, repugnant to
reason, but so many preternatural conditions and
such a multiplication of natural powers are assum-
ed, that it is perfectly irreconcileable with sound
physiology.

Add to this, that, of the phenomena adduced in its
favour, no one is sufficiently consonant with truth to
establish the hypothesis.§

On the other hand, we have indubitable observations
which refute it directly and completely.

586. The less this hypothesis of evolution, as it is
commonly termed, is found consonant with fact and
the rules of philosophising, the more strongly does the
opposite opinion recommend itself to our notice by its
simplicity and correspondence with nature, supposing,
as it does, not an evolution of fictitious germina by
conception, but a true and gradual formation of a new
conception from the hitherto formless genital matter.

[Seite 376]

587. This true generation by successive formation
has been variously described by physiologists, but the
following we consider as the true account.

1. The matter of which organised bodies, and there-
fore the human frame, are composed, differs from all
other matter in this, – that it alone is subject to the
influence of the vital powers.*

2. Among the orders of vital powers, one is emi-
nently remarkable and the least disputable of all,
which, while it acts upon that matter, hitherto shapeless
but mature, imparts to it a form regular and definite,
although varying according to the particular nature of
the matter. To distinguish this vital power from the
rest, permit us to designate it by the term – nisus
formativus
.

3. The nisus formativus occurs to the genital matter,
when this is mature and committed to the uterus in a
proper condition and under proper circumstances, lays
in it the rudiments of conception, and gradually forms
organs fitted for particular purposes; preserves this
structure during life, by nourishing (455 sq.) the body;
and reproduces, (459) as far as it can, any part acci-
dentally mutilated.

588. We therefore think it very probable that those
fluids which, during a successful coition, are thrown
[Seite 377] into the cavity of the uterus, (527, 533, 551.) require a
certain period for becoming intimately mixed, acted
upon, and matured; that, after this preparatory stage,
the nisus formativus is excited in them, vivifying and
shaping the hitherto shapeless spermatic matter partly
into the beautiful containing ovum (565) and partly into
the contained embryo; (569) and that this is the reason
of our inability, notwithstanding the present perfec-
tion of optical instruments, to discover, during the first
weeks after conception, any thing more than shapeless
fluids, without the faintest trace of the form of an
embryo, which, however, about the third month, sud-
denly, as it were, becomes observable.

589. We should exceed the limits of these institu-
tions, were we to adduce many of the arguments which
may be drawn from facts, to illustrate, as, in our
opinion, they most clearly do, the great influence of
the nisus formativus in generation. We will, however,
venture to mention, as briefly as possible, a few,
whose weight will, on a little close reflection, be suf-
ficiently evident.

590. Such, in the history of hybrid animals, is the
[Seite 378] singular experiment of impregnating those which are
prolific, for many generations, with male semen of
the same species, by means of which the form of the
young hybrids becomes so progressively different from
the original maternal configuration, as to approach
more and more to that of the father, till, by a kind
of arbitrary metamorphosis, it is absolutely converted
into it.*

591. Such in our knowledge of monsters (which,
according to the hypothesis of evolution, are nearly
all maintained to have pre-existed in the germs from
the first creation), is the well known fact – that among
certain domestic species of animals, and especially
among sows, monstrosities are very common, whereas
in the original wild variety they are extremely un-
common.

592. While the phenomena of reproduction are all
much more explicable by the nisus formativus than
by the pre-existence of germs for every part, some
particular instances (v.c. that of the nails, which,
after the loss of the first phalanx of the fingers,
have been known to be reproduced on the neighbour-
ing middle phalanx,) admit evidently of no other
solution.

593. From an impartial view of each side of the
question, it will clearly appear, that the defenders of
the germs must allow to the male semen, not only an
exciting power, as they do, but likewise great formative
powers, and thus their doctrine stands in need of the
[Seite 379] assistance of the nisus formativus; while our ex-
planation, on the contrary, is sufficient, without the
aid of pre-existing germs, to explain the phenomena
of generation. There can consequently be no reason
for multiplying the entia, as they are called, unneces-
sarily. (A)


NOTES.

(A) The nisus formativus produces a being generally resem-
bling the parents, but occasionally different. This subject will
be fully treated of in the note on the varieties of mankind.

It is not probable that the ardor of the procreants affects the
energy of the offspring. But from the days of Aristotle it has
been remarked that bastards are very frequently endowed with
great genius and valour, and both ancient and modern history
certainly afford many such examples; and the circumstance has
been commonly ascribed to the impetuosity of the parents during
their embraces. Shakspeare, in King Lear, introduces Edmund
bursting into this indignant soliloquy: –

‘“Why bastard? wherefore base?’
‘When my dimensions are as well compact,’
‘My mind as generous, and my shape as true,’
‘As honest madam’s issue? Why brand they us’
‘With base? with baseness? bastardy? base? base?’
‘Who in the lusty stealth of nature take’
‘More composition and fierce quality’
‘Than doth, within a dull, stale, tired bed’
‘Go to the creating a whole tribe of fops’
‘Got ’tween sleep and wake?”’

‘“Hercules, Romulus, Alexander (by Olympia’s confession),
Themistocles, Jugurtha, King Arthur, William the Conqueror,
[Seite 380] Homer, Demosthenes, P. Lumbard, P. Comestor, Bartholus,
Adrian the fourth Pope, &c. were bastards; and in almost every
kingdom the most ancient families have been at first princes
bastards, the worthiest captains, best wits, greatest scholars,
bravest spirits in all our annals, have been base. Cardan, in his
subtleties, gives a reason, &c. – Corpore sunt et animo fortiores
spurii, plerumque ab amoris vehementiam, &c.”’* Were this
explanation satisfactory, the first fruits of wedded love would
still generally be on an equality with illegimate offspring. If
a greater proportion of illegitimate than of legitimate persons
have really rendered themselves illustrious, their superior energy
may be attributed to the strength of their parents’ constitutions,
it not being likely that the weak and delicate so frequently
become the prey of unlawful passions as the vigorous, and to the
necessity in which such individuals usually find themselves to rely
upon their own exertions.

The vulgar are satisfied that mental impressions made upon
the mother may affect the offspring. If I profess the same
opinion, some will no longer wonder at my being a Christian, nor
others at my being an admirer of Gall and Spurzheim. Credulous,
however, as I may seem, I do confess that so many extraordinary
coincidences, both in the human and the brute subject, have
come to my knowledge, that I dare not affirm the common
belief to be altogether unfounded. That neither all nor most
mal-formations can be thus explained, that pregnant women are
frequently alarmed without such consequences even when most
dreaded, and that highly ridiculous resemblances are fancied to
preceding longings and alarms that were forgotten or may be
well suspected to have never existed, is incontestable. But, in other
matters, when a circumstance may proceed from many causes,
we do not universally reject any one because it is frequently al-
leged without reason. To argue from the non-appearance of
[Seite 381] nerves in the umbilical chord, would be unworthy of the pre-
tension to an enlarged acquaintance with physiology. How
those who believe the Divine authority of every part of their
Bible can reconcile the success of Jacob’s stratagem* (so an-
ciently was the remark common) with their contempt for the
vulgar belief, they best can tell.

SECT. XLI.
OF LABOUR AND ITS SEQUELAE.

[Seite 382]

594. The foetus, formed by the powers already de-
scribed, and having reached the period of full maturity,
has to come into the world by means of labour.*

595. This critical period occurs naturally (and phy-
siology treats solely of natural occurrences) at the end
of the tenth lunar month from conception, i.e. about
the 39th or 40th week.

596. At that time, the pregnant woman is impelled
to bring forth by an absolute necessity, less under the
influence of the will than any other voluntary function
(287).

597. Physiologists have differed in their explana-
tions of the causes of so determinate and sudden an
event. After all, the exciting cause of labour must
be ascribed to an established law of nature, hitherto
equally inexplicable as so many other periodical phe-
nomena; v.c. the metamorphosis of insects, the stages
of exanthematic fevers, crises, &c. &c. nor has the
mature ovum been inaptly compared, caeteris paribus,
to fruit, which, when ripe, falls almost spontaneously
to the ground, from the constriction of those vessels
which previously conveyed its nourishment. And in
fact it has been remarked that the human placenta, at
[Seite 383] the approach of labour, is contracted, and, as it were,
prepared for its separation from the uterus.

What is usually urged respecting the utmost expan-
sion of the uterus, and other similar excitements to
labour, is refuted by many circumstances, and, among
the rest, by the numerous examples of extra-uterine,
whether tubal or ovarian, conceptions, in which, at
the expiration of ten months from impregnation, the
uterus, notwithstanding its vacuity, is seized with the
customary, though indeed fruitless, pains.*

598. Besides this exciting cause, other very power-
ful efficient causes are requisite, as must be manifest
from the relation of the ovum to the uterus.

We are persuaded that the proximate and primary
cause, is solely the vita propria of the uterus. (42, 547.)

Among the remote, the most important appears to be
the respiratory effort excited principally by the great
connection of the intercostal nerve with the rest of the
nervous system.

599. We formerly noticed (582) that, in the latter
periods of pregnancy, the uterus somewhat subsided, by
which circumstance the form of the abdomen is a little
changed and the inconveniences induced during ad-
vanced pregnancy in the function of respiration are
relieved. At the same time, the vaginal mucus (543)
is secreted more abundantly, the vagina itself is re-
laxed, the columns of rugae are almost obliterated,
and the labia pudendi swell; finally, near the approach
of labour, the os uteri gradually dilates into a circular
opening.

[Seite 384]

600. The phenomena of labour generally observe a
regular order of commencement and cessation,* whence
accoucheurs have divided them into stages, of which
the moderns enumerate four, although they define them
variously.

601. In the first, the true pains occur, peculiar in
their nature, proceeding from the loins downwards in
the direction of the uterus (recurring, at intervals, in-
deed, during the whole of labour, with various degrees
of violence and frequency), mild in the beginning, at
which time they are called warning and the os uteri
begins evidently to dilate. The abdomen now falls
still more, the urine is urgent, and abundance of mucus
flows from the soft and tumid genitals.

602. In the second, the pains, increasing, are called
preparing, and, by the compressing effect of the res-
piratory organs, a strong inspiration, &c. a segment of
the lower part of the membranes of the ovum is pro-
truded through the uterine orifice into the vagina.

603. In the third, the pains, becoming more excru-
ciating, are called labour pains, and act with still more
violence upon the uterus, which is driven downwards
and compressed against the foetus, so that the pro-
truded segment of membranes becomes extremely tense,
is burst asunder, and the greater part of the liquor
amnii escapes.

604. Finally, in the fourth and last stage, the pains,
becoming dreadfully violent and agitating, are accom-
[Seite 385] panied by great exertions of the woman herself; al-
most always too by shivering, shrieking, tremor of the
knees, &c. The head of the child, now on the verge of
birth, penetrates, and the face first appears, the vertex
usually remaining under the arch of the pubes and the
rest of the head in the mean time being farther propelled
and revolving around the impacted vertex as around an
axis. Thus the child comes into the world, in the midst
of a red discharge, consisting of a second portion of
the liquor amnii mixed with blood.

605. Soon after the expulsion of the child, the after-
labour
commences, attended by a painful though much
less violent exertion, and followed by another he-
morrhage from that part of the cavity of the womb* to
which the placenta had adhered by means of the de-
cidua crassa.

606. Immediately that both burthens are expelled,
the uterus begins gradually to contract, until it ac-
quires its original form and very nearly its original
dimensions.

607. For about a week after labour, the lochia are
[Seite 386] discharged, for the most part very similar to the cata-
menia, but rather more copious, especially if the mo-
ther does not suckle her offspring. About the sixth
day their red colour becomes fainter, and afterwards
changes to white. At the same time the uterus is libe-
rated from the remaining shreds of the decidua, and,
having thus completed the function of pregnancy, is
again ready for menstruation or conception.

SECT. XLII.
OF THE MILK.

[Seite 387]

608. The breasts, most sacred fountains, and, as
Gellius Favorinus the philosopher elegantly calls them,
the rearers (educatores) of the human race, are inti-
mately connected with the uterus in various ways. The
functions of neither can properly be said to exist dur-
ring infancy; at puberty, both begin to flourish, – when
the catamenia appear, the breasts assume some degree
of plumpness; from that period they undergo either
simultaneous changes, – the breasts beginning to swell
and secrete milk during the pregnancy of the womb, or
alternate changes, – the catamenia ceasing while the
child is suckled, or the lochia becoming copious if the
child is not suckled, and s.p. Finally, when age
creeps on, the function of each absolutely ceases, –
when the catamenia disappear, both the uterus and the
breasts become equally inert. I omit pathological phe-
nomena; v.c. those which occur in irregular menstru-
ation, leucorrhoea, after extirpation of the ovaria, and
in other morbid affections.

609. If this intimate connection is kept in view, we
shall not be astonished that nearly every description of
sympathy formerly mentioned (56) exists between these
organs of the female thorax and abdomen.*

[Seite 388]

610. The influence of the anastomatic sympathy be-
tween the internal mammary and epigastric artery,*
although formerly overrated, is evinced by the change
which the latter experiences in its diameter during preg-
nancy and suckling.

611. Both the uterus and mammas appear to have a
kind of affinity for the chyle, observable in many dis-
eases and nearly always in new-born children.

612. The breast of women, belonging to the most
characteristic marks of the human female both by its
form during the flower of age and by the longer conti-
nuance of this form after the period of suckling than
occurs in any other female animal, is composed of a
placentiform series of conglomerate glands, divided by
numerous furrows into larger lobes, and buried in a
mass of fat; the anterior part swells out particularly
with a firmer description of fat over which the skin is
exceedingly thin.

613. Each of these lobes is composed of still smaller
lobes, and these of acini, as they are termed, to which
the extreme radicles§ of the lactiferous ducts adhere,
deriving a chylous fluid from the ultimate twigs of the
internal mammary arteries.

614. These radicles, gradually uniting,ǁ form large
trunks, corresponding in number with the lobes, – about
[Seite 389] fifteen in each breast. These are every where dilated
into large sinuses, but have no true anastomosis with
each other.*

615. These trunks terminate in very delicate excre-
tory canals, that are collected, towards the centre,
by means of cellular substance, into the nipple, which,
supplied with extremely fine blood-vessels and nerves,
is capable of a curious erection on the approach of
certain external stimuli.

616. The nipple is surrounded by the areola, which,
as well as the nipple, is remarkable for the colour§ of
the reticulum under the cuticle,ǁ and contains sebaceous
follicles.**

617. The secretion of the breast is the milk, well
known in colour, watery, somewhat fatty, rather sweet,
bland, resembling in all respects the milk of domestic
animals, but subject to infinitely greater varieties in the
proportion of its constituent parts, far more difficult of
coagulation from the great quantity of salt which it
contains, and affording no trace of volatile alkali.††

618. When coagulated by means of alcohol, it dis-
[Seite 390] covers the same elements as the milk of other animals.
Besides the aqueous halitus which it gives off when
fresh and warm, the serum, separating from the caseous
part, contains sugar of milk* and acetic acid mixed
with phosphate of lime and of magnesia and with oil
and mucus. The butyraceous cream is said to con-
sist of globules of various and inconstant size, their
diameter ranging between 1/200 and 1/600 of a line. (A)

619. The analogy between chyle and blood, and be-
tween both these fluids and milk, renders it probable
that the milk is a kind of reproduced chyle, again sepa-
rated from the blood before its complete assimilation.
This idea is strengthened by the frequent existence in
the milk of the particular qualities of food previously
taken,§ and by the chylous appearance of the watery
milk secreted during pregnancy and immediately after
labour.ǁ

[Seite 391]

620. The reason why this bland nourishment of the
foetus becomes more thick and rich by continued suck-
ling, is probably the abundance of lymphatics in the
breasts. Those vessels continually absorb more of the
serous part of the milk, in proportion as its secretion is
more copious and of longer standing, and, by again
pouring this part into the mass of blood, promote the
secretion (477): after weaning they take up the remain-
ing milk and mix it with the blood.

621. The milk is secreted in greatest quantity imme-
diately after delivery; and, if the infant sucks, amounts
to one or two pounds every twenty-four hours, until
the menses, which usually cease during suckling, (556)
return.

Occasionally virgins, and new-born infants of either
sex, nay even men,* as well as the adult males of other
mammalia, have been known to furnish milk.

622. The abundance of milk excites its excretion, and
even causes it to flow spontaneously: but pressure, or
the suction of the child, completes its discharge. (B)

NOTES.

[Seite 392]

(A) The lower portion of cows’ milk that had stood some days
was found by Berzelius* to have a specific gravity of 1.033.
and to contain

Water 928.75
Cheese with a trace of butter 28.00
Sugar of milk 35.00
Muriate of potash 1.70
Phosphate of potash 0.25
Lactic acid, acetate of potash, with a trace of
lactate of iron

6.00
Earthy phosphates 0.30
–––––––
1000.00
–––––––

The supernatant cream contained

Butter 4. 5
Cheese 3. 5
Whey 92. 0

(B) It may be worth while here to take a general view of the
subject of generation.

Life never occurs spontaneously in matter, but is always pro-
pagated from an organised system already endowed with it. Such,
at least, appears to be the inevitable conclusion from the facts
within our observation. No instance has been known of a plant
or animal of any species, whose mode of multiplication may be
always easily examined, springing up spontaneously; and although
in many other cases the origin often cannot be discovered, yet
surely our inability to discover the mode of propagation does not
justify us in denying the existence of it; but, the general ana-
logy, the discovery of the modes in which many species propa-
gate which were formerly adduced as instances of spontaneous
[Seite 393] generation, and the occasionally manifest source of the difficul-
ties which obstruct our enquiries, lead necessarily to the belief,
not of the unreality of the fact, but of our deficient penetration.*

The simplest mode of increase is by the detachment and inde-
pendent existence of a portion of a system. In this way trees,
polypes, some worms, and many animalcules, multiply.

Next comes the formation of the rudiments of a perfectly new
being by the system of another. Thus we have the seed of ve-
getables, the ova and foetus of animals. This occurs by means
of two matters, which in some examples are furnished by the
same, and in others, by different, systems. The vegetable king-
dom affords innumerable instances of the former, the acephalous
mollusca and the echinus are examples in the animal kingdom.§
Both the vegetable and animal kingdoms abound in instances of
the latter. Here again there are three varieties. The fluid of
the male may be applied to the ova of the female after they are
discharged from her body, as in fish of the bony kind and in
[Seite 394] cephalopodous mollusca; while being discharged, as in the frog
and toad; or it may be conveyed to the female system, and this
either without the contact of the male, as in vegetables, where
the wind, insects, &c. convey it, or by means of copulation, as
in the mammalia,* birds, most reptiles, and some fish. In the
mammalia, one copulation is sufficient for only one conception;
among poultry its effects are so extensive, that a hen will lay
a long succession of fruitful eggs after one intercourse with the
cock; in the aphis and some monoculi, it is sufficient for the
impregnation of several generations.

The ovum after its formation may be nourished by a fluid en-
closed within the same case, and is then hatched out of the body
by the common temperature, as in insects, or by that of the
parent, as in birds, or hatched within the body of the mother,
as in serpents; or it may be nourished by a substance shed
around it in the womb, as in the kangaroo, or by means of an
attachment of some of its vessels to the maternal system, as in
[Seite 395] the mammalia in general: – some animals being thus oviparous,
others ovoviviparous, and others viviparous.

The mode of nourishment after birth is various. Some are
able, without any peculiar arrangement, immediately to support
themselves; for the wisdom of the Creator ordains the delivery
of each species of animals at that season of the year when every
thing is in the most favourable state for administering to the
necessities of the offspring. Some, many insects for example, are
born in the midst of food, the parent having instinctively deposited
the egg in nutrient matter either found in mass or carefully col-
lected by her. Others have food collected daily by the parents.
Some, as all the dove kind, are fed by a substance secreted from
the crops of both parents;* others by a fluid secreted by peculiar
glands belonging to the female only. The instinct which leads
the parent carefully to tend the offspring, ceases at the period when
the system of the offspring is sufficiently advanced to supply its
own exigencies, and the parent does not breed again till this is
the case.

SECT. XLIII.
OF THE DIFFERENCES IN THE SYSTEM BEFORE AND
AFTER BIRTH.*

[Seite 396]

623. From what has been said relatively to the
functions of the foetus still contained within its mother
and immersed as it were in a warm bath, there must
evidently be a considerable difference between its ani-
mal functions and those of the child that is born and
capable of exerting its will. The chief points of dif-
ference we shall distinctly enumerate.

624. To begin with the blood and its motion, this
fluid is remarkable both for being of a darker red,
incapable of becoming florid on the contact of atmos-
pheric air, and for coagulating less readily and per-
fectly than after birth. Its course too is very different
in the foetus whose circulation is connected with the
placenta and who has never breathed, from its course
[Seite 397] after the cessation of this connection with the mother
and after respiration has taken place.*

625. First, the umbilical vein, coming from the pla-
centa and penetrating the ring called umbilical, runs
to the liver, and pours its blood into the sinus of the
vena portae, the branches of which remarkable vein
distribute one portion through the liver, while the
ductus venosus Arantii conveys the rest directly to
the inferior vena cava.

Both canals, – the end of the umbilical vein contained
in the abdomen of the foetus, and the venous duct,
become closed after the division of the chord, and the
former is converted into the round ligament of the
liver.

626. The blood, arriving at the right side of the heart
from the inferior cava, is in a great measure prevented
from passing through the lungs, and is derived into the
left or posterior auricle of the heart, by means of the
Eustachian valve and the foramen ovale.

627. For, in the foetus, over the opening of the in-
ferior cava, there is extended a lunated valve, termed,
from its discoverer,§ Eustachian, which usually dis-
[Seite 398] appears as adolescence proceeds, but, in the foetus,
appears to direct* the stream of blood coming from
the abdomen towards an opening, immediately to be
mentioned, existing in the septum of the auricles.

628. This opening is denominated the foramen ovale,
and is the cause that certainly the greatest part of the
blood which streams from the inferior cava is poured
into the left auricle during the diastole of the auricles.
A falciform valve, placed over the foramen, prevents
its return, and appears likewise to preclude its course
into the left auricle during the systole of the auricles.
By means of this valve, the foramen generally becomes
closed in early infancy in proportion as the correspond-
ing Eustachian valve decreases and more or less com-
pletely disappears.§

629. The blood which enters the right auricle and
ventricle principally proceeds from the superior cava,
and flows but in a very small quantity into the lungs,
while, from the right ventricle, which, in the foetus, is
particularly thick and strong for this purpose, it pur-
sues its course directly to the arch of the aorta, by
means of the ductus arteriosus,ǁ which is in a manner
the chief branch of the pulmonary artery. A few weeks
[Seite 399] after birth, this duct becomes obstructed and converted
into a kind of dense ligament.

630. The blood of the aorta, being destined to return,
in a great measure, to the mother, enters the umbilical
arteries
(572), which pass out on each side of the ura-
chus at the umbilical opening, and, after birth, likewise
become imperforate chords.*

631. As the function of the lungs scarcely exists in
the foetus, their appearance is extremely different from
what it is after the commencement of respiration. They
are proportionally much smaller, their colour is darker,
their substance denser, consequently their specific gra-
vity is greater, so that while recent and sound they
sink in water, whereas, after birth, they, caeteris pari-
bus, swim upon its surface. The right lung has the
peculiarity of dilating during the first inspiration rather
sooner than the left. The other circumstances attend-
ing the commencement of respiration were described in
the section upon that function.

632. From our remarks upon the nutrition of the
foetus, it is clear that its alimentary tube and chylo-
poietic system must be very peculiar. Thus, v.c. in
an embryo a few months old, the large intestines very
[Seite 400] nearly resemble the small; but, during the latter half
of pregnancy, being turgid with meconium, they really
deserve the epithet by which they are commonly
distinguished.

633. The meconium is a saburra, of a brownish green
colour, formed evidently from the secreted fluids of the
foetus, and chiefly from its bile, because it is first
observed at the period corresponding to the first secre-
tion of the bile; and in monstrous cases, where the
liver has been absent, no meconium, but merely a small
quantity of colourless mucus, has been found in the
intestines.

634. The caecum is extremely different in the new
born child from its future form, and continued straight
from the appendix vermiformis, &c.*

635. Other similar differences we have already spoken
of, and shall now pass over. Such are the urachus (573),
the membrana pupillaris, (262) the descent of the testes in
the male, (510 sq.)

Some will be treated of more properly in the next
section. Others, of little moment, we shall entirely
omit.

636. This is a favourable opportunity for briefly
noticing some remarkable parts which are out of all
proportion larger in the foetus and appear to serve im-
portant purposes in its economy, although their true
and principal design deserves still further investigation.
They are usually styled glands, but their parenchyma
is very different from true glandular structure, nor has
any vestige of an excreting duct been hitherto dis-
[Seite 401] covered in them. They are the thyreoid, the thymus,
and the supra-renal glands.*

637. The thyreoid gland is fixed upon the cartilage
of the same name belonging to the larynx, has two
lobes, is, as it were, lunated, and full not only of
blood, in which it abounds in the foetus, but of lym-
phatic fluid, and becomes, as age advances, gradually
less juicy.§

638. The thymus is a white and very tender structure,
likewise bilobular, sometimes completely divided into
two parts, occasionally containing a remarkable ca-
vity,ǁ placed under the superior part of the middle of
the sternum, always ascending as far as the neck on
each side,** of extremely great proportionate size in
the foetus, abounding in a milky fluid, becoming gra-
dually absorbed in youth, and frequently disappearing
altogether in old age.††

[Seite 402]

639. The supra-renal glands, called also renes suc-
centuriati and capsulae atrabiliariae, lie under the dia-
phragm on the upper margin of the kidneys,* from
which, in the adult, they are rather more distant, being
proportionally smaller. They are full of a dark fluid
of a more reddish hue in the foetus than in the adult.


NOTE.

Blumenbach has omitted here to notice one of the most striking
peculiarities of the foetus, – the very great proportionate bulk of
its liver. The prodigious size of this organ arises from the dis-
tribution of four-fifths of the blood of the umbilical vein through
it, and probably, in a certain degree, as some think, from the
great quantity of meconium in its biliary ducts. After birth, no
blood is conveved by the umbilical vein, and the expansion of
the thorax readily expresses the abundance of meconium; hence
the liver must diminish.

This peculiarity, as well as the great size of the thyreoid,
thymus, and supra-renal glands, probably serves some purpose
hitherto undiscovered, but an evident good effect results from it
in relation to the organs of the thorax. In the foetus the lungs
are completely devoid of air, and consequently there cannot be
much, if any, circulation of blood through the pulmonary artery
and veins, and the liver by its magnitude, protruding the dia-
phragm upwards, renders the capacity of the chest correspond-
ently small, and at the same time it contains an immense pro-
portion of blood. After birth, the diminished size of the liver
[Seite 403] allows a great increase to the capacity of the chest; not only
is full inspiration allowed, and consequently a free passage to the
blood of the pulmonary vessels during inspiration, as Haller re-
marks,* but a certain degree of permanent dilatation of the
lungs is allowed (for much air remains in the lungs after every
expiration), and as the liver contains, immediately after birth, so
much smaller a portion of the blood of the system than before,
the greatly increased supply required by the lungs is thus afforded.
See Note B. Sect. VIII.

SECT. XLIV.
OF THE GROWTH, STATIONARY CONDITION, AND
DECREASE OF THE HUMAN SYSTEM.

[Seite 404]

640. Nothing more remains at present than to
survey at one view the natural course of the life of
man, whose animal functions we have hitherto arranged
in classes and examined individually, and to accom-
pany him through his principal epochs from his birth
to his grave.*

641. The commencement of formation appears to take
place about the third week from conception (569), and
genuine blood is first observable about the fourth, the
life of the foetus at this period being extremely faint (82)
and little more than that of a vegetable; the motion
of the heart
(98) has, under fortunate circumstances,
been observable at this time in the human embryo,
though long ago detected by Aristotle in the incubated
egg and ever since his time denominated the punctum
saliens.

The original form of the embryo is simple, and, as it
were, disguised, wonderfully different from the perfect
conformation of the human frame, which deserves to
[Seite 405] be regarded as the grandest effect of the nisus forma-
tivus, and at which it arrives by gradual changes or, if
we may so speak, metamorphoses, from a more simple
to a more perfect form.*

642. The formation of human bone begins, if we are
not deceived, in the seventh or eighth week. First of
all, the osseous fluid forms its nuclei in the clavicles,
ribs, vertebras, the large cylindrical bones of the ex-
tremities, the lower jaw, and some other bones of the
[Seite 406] face, in the delicate reticulum of some flat bones of
the skull, – of the frontal and occipital, but less early
in the parietal. In general, the growth of the embryo,
and indeed of the human being after birth, is more
rapid as the age is less, and vice versa. (A)

643. About the middle of pregnancy, certain fluids
begin to be secreted, as the fat (486) and bile. In the
course of the seventh month, all the organs of the vital,
natural, and animal, functions have made such progress,
that, if the child happens to be born at this period, it
is called, in a common acceptation of the word, vital,
and regarded as a member of society.

644. In the foetus, near its full growth, not only is
the skin covered by a caseous matter, but delicate hair
appears upon the head,
and little nails become visible;
the membrana pupillaris splits (262); the cartilaginous
external ear becomes more firm and elastic; and in the
male the testes descend. (510 sq.)

645. About the end of the tenth lunar month, the
child, being born (595), undergoes, besides those impor-
tant changes of nearly its whole economy which were
formerly described at large, other alterations in its ex-
ternal appearance;
v.c. the down which covered its
face at birth gradually disappears, the wrinkles are
obliterated, the anus becomes concealed between the
swelling nates, &c.

646. By degrees the infant learns to employ its
mental faculties of perception, attention, reminiscence,
inclination, &c. whence, even in the early months, it
dreams, and s.p.*

[Seite 407]

647. The organs of the external senses are gradually
evolved and perfected, as the external ear, the internal
nares, the coverings of the eyes, viz. the supra-orbital
arches, the eyebrows, &c.

648. The bones of the skull unite more firmly; the
fonticuli are by degrees filled up; and, about eight
months after birth, dentition commences.

649. At this period the child is ready to be weaned,
its teeth being intended to manducate solid food and
not to injure the mothers breast.

650. About the end of the first year, it learns to rest
upon its feet and stand erect, – the highest characteristic
of the human body.*

651. The child, now weaned from its mother’s breast
and capable of using its feet, improves and acquires
more voluntary power daily: another grand privilege
of the human race is bestowed upon it, – the use of
speech, – the mind beginning to pronounce, by means of
the tongue, the ideas with which it is familiar.

652. The twenty milk teeth by degrees fall out about
the seventh year, and a second dentition produces, in
the course of years, thirty-two permanent teeth.

653. During infancy, memory is more vigorous than
the other faculties of the mind, and much more powerful
than at any other period in tenaciously receiving the
impressions of objects: after the fifteenth year, the fire
of imagination burns more strongly.

654. This more lively state of the imagination occurs
very opportunely at puberty, when the body, under-
[Seite 408] going various remarkable changes, is being gradually
prepared for the exercise of the sexual functions.

655. Immediately after the period when the breasts
of the adolescent girl have begun to swell, the chin of
the boy is covered with down, and other phenomena of
approaching puberty manifest themselves in either sex.
The girl begins to menstruate (554), – an important
change in the female economy, accompanied, among
other circumstances, nearly always, by an increased
brightness of the eyes and redness of the lips and by
more evident sensible qualities of the perspiration.
The boy begins to secrete genuine semen (527), and, at
the same time, the beard* grows more abundantly, and
the voice becomes extremely grave.

By the spontaneous internal voice of nature, as it
were, the sexual instinct (71) is now for the first time
excited, and man, being in the flower of his age, is ca-
pable of sexual connection.

656. The period of puberty cannot be exactly defined:
it varies with climate and temperament, but is gene-
rally more early in the female; so that, in our climate,
girls arrive at puberty about the fifteenth year, and
young men, on the contrary, about the twentieth. (B)

657. Soon after this, growth terminates; at various
[Seite 409] periods in different climates, to say nothing of particular
individuals and families.* (C)

658. The epiphyses of the bones, hitherto distinct
from their diaphyses, now become intimately united,
and, in a manner, confounded with them.

659. At manhood – the longer and more excellent pe-
riod of human existence, life is, with respect to the cor-
poreal functions, at the highest pitch (82), or, in other
words, these functions are performed with the greatest
vigour and constancy; in regard to the mental func-
tions, the grand prerogative of mature judgment is now
afforded.

660. The approach of old age is announced in wo-
men by the cessation of the catamenia (556), and not
unfrequently by an appearance of beard upon the chin;
in men, by less alacrity to copulate: in both, by a se-
[Seite 410] nile* dryness and a gradually manifested decrease of
vital energy.

661. Lastly, the frigid condition of old age is accom-
panied by an increasing dulness of both the external
and internal senses, a necessity for longer sleep, and a
torpor of all the functions of the system. The hairs
grow white and partly fall off. The teeth gradually
drop out. The neck is no longer able to give due sup-
port to the head, nor the legs to the body. Even the
bones themselves – the props of the machine, in a man-
ner waste away, &c.

662. Thus we are conducted to the boundary of
physiology, – to death without disease, – to the senile
εὐθανασία, which it is the first and last object of medi-
cine to procure, and the cause of which must be self-
evident from our preceding account of the animal
economy.§

663. The phenomena of a moribund personǁ are cold-
ness of the extremities, loss of brilliancy of the eyes,
smallness and slowness of the pulse, which more and
more frequently intermits, infrequency of respiration,
which at length terminates for ever by a deep expiration.
[Seite 411] In the dissection of other moribund mammalia the
struggle of the heart may be perceived, and the right
auricle and ventricle are found to live rather longer than
the left. (117)

664. Death is manifested by the coldness and rigidity
of the body, the flaccidity of the cornea, the open state
of the anus, the lividness of the back, the depression
and flatness of the loins (59 note), and, above all, by an
odour truly cadaverous.* If these collective marks are
present, there can scarcely be room for the complaint of
Pliny, – that we ought not to feel assured of the fate of
a man though we see him lie dead. (D)

665. It is scarcely possible to define the natural pe-
riod
of life, or, as it may be termed, the more frequent
and regular limit of advanced old age. But, by an
accurate examination of numerous bills of mortality, I
have ascertained a remarkable fact – that a pretty large
proportion of Europeans reach their eighty-fourth year,
while, on the contrary, few exceed it. (E)

666. On the whole, notwithstanding the weakness of
children, the intemperance of adults, the violence of
diseases, the fatality of accidents, and many other cir-
cumstances, prevent more than about perhaps seventy-
eight persons out of a thousand from dying of old age,
[Seite 412] without disease; nevertheless, if human longevity* be
compared, caeteris paribus, with the duration of the life
of any other known animal among the mammalia, we
shall find that, of all the unreasonable whinings about
the misery of human life, no one is more unfounded
than that which we commonly hear respecting the short-
ness of its duration. (F)


NOTES.

(A) For a minute account of ossification I refer to Mr. How-
ship’s papers in the Medico-Chirurgical Transactions.

(B) Instances continually occur in both sexes of early puberty,
sometimes joined with very rapid growth. The mind however
does not usually keep pace with the body, (or rather the brain
with the rest of the body) nor are such individuals commonly
long lived. Some males are reported to have been adult before
the completion of their first year, an instance of which will pre-
sently be given in note C. One of the earliest examples of fe-
male puberty is related in the Medico-Chirurgical Transactions:
the girl began to menstruate when not three years of age, and
soon after acquired large breasts, broad hips, &c. Schurig
quotes numerous, and for the most part probably fabulous, in-
stances of fecundity in either sex between the seventh and twelfth
year, and one of a little couple, he nine and she eight, who ma-
naged to beget a child.

The activity of the grand organs of generation, – the testes in
[Seite 413] the male and the ovaria in the female, is so connected with the
great changes that occur in the rest of the generative organs
and in the system at large at the period of puberty, that these
changes are prevented if those organs are previously removed,
and are in general proportional to their evolution and activity;*
and, if their removal is practised after puberty is established, the
system more or less relapses into its former condition or acquires
the characteristics of the opposite sex. This is well known in re-
gard to brutes and the males of our species. We have one instance
of the castration of a woman: her ovaria protruded at the groins
and were so troublesome as to induce her to submit to their
removal in St. Bartholomew’s Hospital; she afterwards grew thin-
ner and more muscular, her breasts shrunk away, and she ceased
to menstruate. When the ovaria have been found deficient, the
signs of puberty had not appeared. The absence of the uterus
only is not attended by any deficiency in the general changes,§
nor does its removal destroy desire or give a woman the characters
of the male. Nay, where it only is absent, there are monthly
pains, and frequently most severe ones, in the pelvis, with all
the attendant circumstances of menstruation, as if the discharge
were taking place.ǁ

[Seite 414]

Mr. Hunter made an experiment respecting the removal of
one ovarium only. He took two young sows in all respects
similar to each other, and, after removing an ovarium from one,
he admitted a boar of the same farrow to each and allowed them
to breed. The perfect sow bred till she was about eight years
old, – a period of almost six years, in which time she had thir-
teen farrows, and in all one hundred and sixty-two pigs; the
other bred till she was six years old, – during a space of more
than four years, and in that time she had eight farrows and in
all seventy-six pigs. Thus it would appear that each ovarium is
destined to afford a certain number only of foetuses, and that the
removal of one, although it does not influence the number of
foetuses produced by the other, causes them to be produced in a
shorter time.*

(C) Not only do instances of early puberty and full growth
frequently occur, but likewise of deficient and exuberant growth.

Dwarfs are generally born of the same size as other children,
but after a few years suddenly cease to grow. They are said to
be commonly ill-shaped, to have large heads, and to be stupid
or malicious, and old age comes upon them very early. The
three foreign dwarfs lately exhibited in London, two men and
one woman, had certainly large heads and flat noses, but in other
respects were well made. The tallest of the three seemed a
sulky creature, but the woman was very ingenious and obliging,
and Simon Paap – the least of the three, appeared very amiable.
He was twenty-eight inches high and twenty-six years old.
[Seite 415] They were not related to each other, and the relations of all
were of the common size. Their countenances were those of
persons more advanced. The smallest dwarf on record was only
sixteen inches high, when thirty-seven years of age.*

The tallest person authentically recorded has never exceeded
nine feet, according to Haller. The young man from Hunting-
donshire, also lately exhibited in London, was of remarkable
height. Although only seventeen years of age, he was nearly
eight feet. He had a sister of great height, and many of his
family were very tall. He was, as is usual, born of the ordinary
size, but soon began to grow rapidly. He appeared amiable,
and as acute as most youths of his age and rank.

Giants and dwarfs providentially seldom reach their fortieth
year and have not very active organs of generation. As the
period of growth is so short in dwarfs, and the period of child-
hood so short in those who reach puberty early, it is to be ex-
pected that their old age will be premature, – that their stationary
period and decline will be likewise short. Giants do not, like
dwarfs, I believe, die from premature old age, but from mere
exhaustion.

[Seite 416]

Hopkins Hopkins, weighing never more than 18lbs. and lat-
terly but 12, died of pure old age at seventeen; and one of his
sisters, but 12 years of age and weighing only 18lbs. at the time
of his death, had all the marks of old age.*

(D) The heavenly serenity of the countenance of most fresh
corpses is a very remarkable, and to me, I confess a very affect-
ing and consolitary, circumstance. I cannot deny myself the
pleasure of forcibly drawing the attention of my readers to it by
quoting some inimitable lines of the mighty and unhappy Byron.

‘“He who hath bent him o’er the dead’
‘Ere the first day of death is fled,’
‘Before decay’s effacing fingers’
‘Have swept those lines where beauty lingers,’
‘And marked the mild angelic air,’
‘The rapture of repose that’s there,’
‘The fixed yet tender traits that streak’
‘The languor of the placid cheek,’
‘And but for that sad shrouded eye’
‘That fires not – wins not – weeps not now.’
‘And but for that chill changeless brow’
‘Where cold obstruction’s apathy’
‘Appals the gazing mourner’s heart’
‘As if to him it could impart’
‘The doom he dreads yet dwells upon,’
‘Yes but for these and these alone,’
‘Some moments, aye, one treacherous hour,’
‘He still might doubt the tyrant’s power:’
‘So fair, so calm, so softly sealed,’
‘The fair last look by death revealed.”’

(E) Our countryman Parr married when a hundred and twenty
years of age, retained his vigour till a hundred and forty, and
died at a hundred and fifty-two from plethora induced by a
change in his diet. Harvey, who dissected him, found no decay
of any organ, and, had not Parr become an inmate of the Earl
[Seite 417] of Arundel’s family in London, he probably would have lived
many years longer. Our other countryman Jenkins, who lived
a hundred and sixty-nine years, is perhaps the greatest authentic
instance of longevity since primitive times.

Longevity frequently runs in families, and is much disposed
to by early rising and matrimony.*

Life is often protracted very long after the teeth have fallen
out and the hair has turned gray.

Dr. Rush gives a striking illustration of the weakness of im-
pressions made in advanced life, while those of earlier date are
well remembered, in the instance of a German woman who had
learned the language of the Americans when forty years old, and,
though still living in America, had forgotten every word of it at
eighty, but talked German as fluently as ever. Bishop Wat-
son’s father married and had a family very late, and when
extremely aged would twenty times a day ask the name of the
lad at college, though he would ‘“repeat, without a blunder,
hundreds of lines, out of classic anthors.”’

It is a most remarkable circumstance that the system frequently
makes an effort at renovation in extreme old age. I myself have
known several old persons cut new teeth, and the Philosophical
Transactions and other works record many similar facts, – even that
of a complete third set. Dr. Rush mentions an old man in Pennsyl-
vania who at sixty-eight lost his sight and remained perfectly
blind for years, though otherwise in complete health: at eighty
he regained his sight spontaneously without any visible change
in the eyes, and could see as well as ever in his life at eighty-
four, when the account was written.

I need scarcely observe that the height and the age of men
at present are the same as they have always been. It is a
common custom to magnify the past. Homer, who flourished
[Seite 418] almost three thousand years ago, makes his heroes hurl stones in
battle which

–––– οὐ δύο γ’ἄνδρε ϕέροιεν
Οἷοι νῦν βροτοί εἰσι.*

Yet the giant who was the terror of the Israelites did not pro-
bably exceed nine feet in height, and it was to David who slew
him and appeared but little more than a century later than Ho-
mer’s heroes that Barzillai thus excused himself for not visiting
the royal palace at Jerusalem: – ‘“I am this day fourscore years
old; and can I discern between good and evil? can thy ser-
vant taste what I eat or what I drink? can I hear any more the
voice of singing men and singing women? wherefore then
should thy servant be yet a burden unto my lord the king?”’
Moses lived five hundred years earlier than David, and writes, –
‘“The days of our years are threescore and ten; and if by reason
of strength they be fourscore years, yet is their strength labour
and sorrow: for it is soon cut off, and we fly away.’


(F) The functions of the human machine having now been
fully described, it may be useful to consider it in its relation to
other animated systems and to review the chief varieties in which
it appears.

Numerous authors have remarked that a gradation exists among
all the objects of the Universe, from the Almighty Creator,
through arch-angels and angels, men, brutes, vegetables, and
inanimate matter, down to nothing.

‘“Vast chain of being which from God began,’
‘Natures ethereal, human, angel, man,’
‘Beast, bird, fish, insect, what no eye can see,’
‘No glass can reach, from infinite to thee,’
‘From thee to nothing.”’§
[Seite 419]

Yet this gradation, striking as it is, deserves not the epithet
regular or insensible. ‘“The highest being not infinite must be,
as has been often observed, at an infinite distance below infinity.”’
‘“And in this distance between finite and infinite there will, be
room for ever for an infinite series of indefinable existence. Be-
tween the lowest positive existence and nothing, wherever we
suppose existence to cease, is another chasm infinitely deep;
where there is room again for endless orders of subordinate beings,
continued for ever and ever, and yet infinitely superior to non-
existence.”’ ‘“Nor is this all. In the scale, wherever it begins
or ends, are infinite vacuities. At whatever distance we suppose
the next order of beings to be above man, there is room for an
intermediate order of beings between them, and if for one order
then for infinite orders; since every thing that admits of more
or less, and consequently all the parts of that which admits them,
may be infinitely divided. So that as far as we can judge, there
may be room in the vacuity between any two steps of the scale,
or between any two points of the cone, for infinite exertion of
infinite power.’

In fact, at how vast a distance do we see the innate mental
properties of man standing above those of the most sagacious
brute! how immensely does the volition of the lowest animal
raise it above the whole vegetable kingdom! and how deep the
chasm between the vital organisation of the meanest vegetable
and a mass of inanimate matter! Gradation must be admitted,
but it is far from regular or insensible. Neither does it at all
regard perfection of system, nor very much the degree, but
chiefly the excellence and, within the limits of the visible world,
the combination, of properties. Man, placed at the summit of
terrestrial objects by the excellence of his mind and the combi-
nation of the common properties of matter, of those of vege-
tables, and of those of brutes, with those peculiar to himself, is
surpassed by the dog in acuteness of smell and by the oak in
[Seite 420] magnitude, nor can he boast of more perfection than the gnat or
the thistle in their kinds.

Bodies consist of Particles endowed with certain properties
without which their existence cannot be conceived, viz. extension
and impenetrability; with others which proceed indeed from
their existence, but are capable of being subdued by opposing
energies, viz. mobility, inertness; and with others apparently
neither necessary to their existence nor flowing from it, but
merely superadded, for example, various attractions and repul-
sions, various powers of affecting animated systems.

Inanimate Bodies have no properties which are not either ana-
logous to these or dependent upon them, are for the most part
homogeneous in their composition, and disposed to be flat and
angular, increase by external accretion, and contain within them-
selves no causes of decay.

Vegetables, in addition to the properties of inanimate matter,
possess those of Life, viz. sensibility, (without consciousness or
perception) and contractility:* their structure, is beautifully
organised, and their surfaces disposed to be rounded, they grow
by internal deposition, and are destined in their nature for a
period of increase and decay.

Animals, in addition to the properties of vegetables, enjoy
Mind, the indispensable attributes of which are the powers of
consciousness, perception, and volition: the two former without
the latter, were, like vegetable or organic sensibility without
contractility, useless; and the latter could not exist without the
two former any more than vegetable or organic contraction
could occur without sensibility: nor can the existence of mind
[Seite 421] be conceived without the faculties of consciousness, perception,
and volition, any more than the existence of matter without
extension and impenetrability. The possession of mind by animals
necessarily implies the presence of a brain for its exertion, and
of a nerve or nerves for the purpose of conveying impressions to
this brain and at least volitions from it to one or more voluntary
muscles. A system which is not thus gifted certainly deserves
not the name of animal.*

Notwithstanding the vast interval which of necessity exists
between the animal and vegetable kingdoms, the lowest brutes
approach as nearly as possible in organisation, and consequently
in function, to vegetable simplicity. They possess merely con-
sciousness, perception, and volition, with the appetite for food,
[Seite 422] and multiply by shoots, fixed like vegetables to the spot which
they inhabit. The five senses, sexual appetite, instincts, memory,
judgment,* and locomotive power, with the necessary organs,
are variously superadded, and endless varieties of organisation
constructed, so that air and water, the crust and the surface of
the earth, are all replenished with animals completely calculated
for their respective habitations.

[Seite 423]

Man, besides the common properties of animals, has others
which raise him to an immense superiority. His mind is endowed
with powers of the highest order which brutes have not, and his
body, being, like the bodies of all animals, constituted in harmony
with the mind that the powers of the latter may have effect,
differs necessarily in many points of construction from the body
of every brute. Well might Shakspeare exclaim, ‘“What a piece
of work is man! How noble in reason! how infinite in faculties!
in form and moving how express and admirable! in action how
like an angel! in apprehension how like a god! the beauty of
the world! the paragon of animals!”’*

The orang-outangs approach the nearest of all brutes to the
human subject. Possessing expression of countenance, elevation
of forehead, and less projection of the lower part of the face than
other brutes, anterior extremities that are really arms and hands,
and teeth of the same number and pretty much of the same
figure as our own; curious, imitative, covetous, social; said by
some to place sentinels and dispose themselves in a train for the
propagation of alarm, to seem now and then to laugh and
weep, to walk a little occasionally erect, to defend themselves
[Seite 424] with sticks and stones, to copulate face to face, to carry their young
either in their arms or on their hacks, and to be very lascivious
in regard to our species; the orang-outangs at first sight afford,
if any of the genus can afford, a little probability to the opinion
of a close connection between apes and the human race. Un-
civilised men, too, make a slight approach in many corporeal
particulars, as we shall hereafter find, to the structure of other
animals, and, since also the circumstances of their existence call
into action few of the peculiar mental powers of our nature, they
have been adduced in corroboration of this opinion. But the
least examination
displays differences of the greatest magnitude
between the human and the brute creation.* These we shall
[Seite 425] review under two divisions, the first embracing the mental, and
the second the corporeal, characteristics of mankind.

In judging of the mental faculties of mankind,* not merely
those should be considered which an unfortunately situated indi-
vidual may display, but those which all the race would display
under favourable circumstances. A seed and a pebble may not
on a shelf appear very dissimilar, but, if both are placed in the
earth, the innate characteristic energies of the seed soon become
conspicuous. A savage may in the same manner seem little
superior to an orang-outang, but, if instruction is afforded to
both, the former will gradually develope the powers of our nature
in all their noble superiority, while the latter will still remain an
orang-outang. The excellence of man’s mind demonstrates
itself by his voice and hands. Witness the infinite variety and
the depth of thought expressed by means of words: witness his
great reasoning powers, his ingenuity, his taste, his upright,
religious, and benevolent, feelings, in his manufactories, his
galleries of the fine arts, his halls of justice, his temples, and his
charitable establishments. Besides the qualities common to all
animals, each of which he, like every animal, possesses in a
degree peculiar to himself, and some indeed in a degree very far
surpassing that in which any brute possesses them, for instance,
benevolence, mechanical contrivance, the sense for music and
languages, and the general power of observation and inference
respecting present circumstances, he appears exclusively gifted
with at least feelings of religion and justice, with taste, with wit,
and with the reflecting faculties of comparing and reasoning into
causes.

The corporeal characteristics of mankind are not less striking
[Seite 426] and noble.* Among the beings beheld by Satan in Milton’s
Paradise,

‘“Two of far nobler shape, erect and tall,’
‘Godlike erect, with native honour clad,’
‘In naked majesty seemed lords of all.”’

The erect posture is natural and peculiar to man. All nations
walk erect, and, among those individuals who have been dis-
covered in a wild and solitary state, there is no well authenticated
instance of one whose progression was on all-fours. If we
attempt this mode of progression, we move either on the knees
or the points of the toes, throwing the legs obliquely back to a
considerable distance; we find ourselves insecure and uneasy;
our eyes instead of looking forwards are directed to the ground;
[Seite 427] and the openings of the nostrils are no longer at the lower part
of the nose, – in a situation to receive ascending odorous particles,
but lie behind it. Our inferior extremities, being of much greater
length, in proportion to the others and to the trunk, than the
posterior of brutes with four extremities, even in children in
whom the proportion is less, are evidently not intended to coin-
cide with them in movement; they are much stronger than the
arms, obviously for the purpose of great support: the presence of
calves, which are found in man alone, shews that the legs are to
support and move the whole machine; the thigh bones are in
the same line with the trunk, in quadrupeds they form an angle,
frequently an acute one; the bones of the tarsus become hard
and perfect sooner than those of the carpus, because strength of
leg is required for standing and walking sooner than strength of
arm and hand for labour; the great toe is of the highest import-
ance to the erect posture, and bestowed exclusively on mankind;
the os calcis is very large, particularly at its posterior projection,
for the insertion of the strong muscles of the calf, and lies at
right angles with the leg; we alone can rest fully upon it, and
in fact upon the whole of the tarsus, metatarsus, and toes. The
superior extremities do not lie under the trunk as they would if
destined for its support, but on its sides, capable of motion
towards objects in every direction; the fore-arm extends itself
outwards, not forwards, as in quadrupeds, where it is an organ
of progression; the hand is fixed not at right angles with the
arm, as an instrument of support, but in the same line, and cannot
be extended to a right angle without painfully stretching the
flexor tendons; the superior extremity is calculated in the erect
posture for seizing and handling objects, by the freedom of its
motions, by the great length of the fingers above that of the toes,
and by the existence of the thumb, which, standing at a distance
from the fingers and bending towards them, acts as an opponent,
while the great toe is, like the rest, too short for apprehension,
stands in the same line with them, and moves in the same direc-
tion: were our hands employed in the horizontal posture, they
[Seite 428] would be lost to us as grand instruments in the exercise of our
mental superiority. Quadrupeds have a strong ligament at the
back of the neck to sustain the head; in us there is no such thing,
and our extensor muscles at the back of the neck are compa-
ratively very weak.* They have the thorax deep and narrow,
that the anterior extremities may lie near together and give more
support; the sternum too is longer, and the ribs extend con-
siderably towards the pelvis to maintain the incumbent viscera;
our thorax is broad from side to side, that the arms being thrown
to a distance may have greater extent of motion, and narrow
from the sternum to the spine; and the abdominal viscera, press-
ing towards the pelvis rather than towards the surface of the
abdomen in the erect attitude, do not here require an osseous
support. The pelvis is beautifully adapted in us for supporting
the bowels in the erect posture; it is extremely expanded, and
the sacrum and os coccygis bend forwards below: in brutes it
does not merit the name of pelvis; for, not having to support
the abdominal contents, it is narrow, and the sacrum inclines
but little to the pubes. The nates, besides extending the pelvis
upon the thigh bones in the erect state of standing or walking,
allow us to rest while awake in the sitting posture, in which, the
head and trunk being still erect, our organs of sense have their
proper direction equally as in walking or standing: were we
compelled to lie down like quadrupeds, when resting during the
waking state, the different organs of the face must change their
present situation to retain their present utility, no less than if we
were compelled to adopt the horizontal progression; and, con-
versely, were their situation so changed, the provision for the
sitting posture would be comparatively useless.

[Seite 429]

While some, perversely desirous of degrading their race, have
attempted to remove a splendid distinction by asserting that we are
constructed for all fours, others with equal perverseness and igno-
rance have asserted that monkeys are destined for the upright pos-
ture. The monkey tribe, it is true, maintain the erect posture less
awkwardly than other brutes with four extremities, but they can-
not maintain it long, and, while in it, they bend their knees and
body; they are insecure and tottering, and glad to rest upon a stick;
their feet, too, instead of being spread for support, are coiled up
as if to grasp something. In fact their structure proves them
to be neither biped nor quadruped, but four-handed, animals.
They live naturally in trees, and are furnished with four hands
for grasping the branches and gathering their food. Of their
four hands the posterior are even the more perfect, and are in
no instance destitute of a thumb, although, like the thumbs of
all the quadrumana, so insignificant as to have been termed by
Eustachius, ‘“omnino ridiculus;”’ whereas the anterior hands of
one variety (simia paniscus) have not this organ. The whole
length of the Orang-outang, it may be mentioned, falls very much
short of ours.

It was anciently supposed that man, because gifted with the
highest mental endowments, possessed the largest of all brains.*
But as elephants and whales surpass him in this respect, and the
sagacious monkey and dog have smaller brains than the com-
paratively stupid ass, ox, and hog, the opinion was relinquished
by the moderns, and man was said only to have the largest brain
in proportion to the size of his body. But as more extensive
observation proved canary and other birds, and some varieties of
the monkey tribe, to have larger brains than man in proportion
to the body, and several mammalia to equal him in this par-
ticular, and as rats and mice too surpass the dog, the horse, and
the elephant, in the comparative bulk of their brains; this opinion
[Seite 430] also gave way, in its turn, to that of Soemmerring, – that man
possesses the largest brain in comparison with the nerves arising
from it. This has not yet been contradicted, although the com-
parative size of the brain to the nerves originating from it
(granting that they originate from it) is not an accurate measure
of the faculties, because the seal has in proportion to its nerves
a larger brain than the house dog, and the porpoise than the
orang-outang.

As the human brain is of such great comparative magnitude,
the cranium is necessarily very large and bears a greater pro-
portion to the face than in any other animal. In an European
a vertical section of the cranium is almost four times larger than
that of the face (not including the lower jaw); in the monkey
it is little more than double; in most ferae, nearly equal; in the
glires, solipedes, pecora, and belluae, less. The faculties, how-
ever, do not depend upon this proportion, because men of great
genius, as Leo, Montaigne, Leibnitz, Haller, and Mirabeau, had
very large faces, and the sloth and seal have faces larger than
the stag, horse, and ox, in proportion to the brain, and the pro-
portion is acknowledged by Cuvier to be not at all applicable to
birds. We are assisted in discovering the proportion between
the cranium and face by the facial angle of Camper. He draws
two straight lines, the one, horizontal, passing through the
external meatus auditorius and the bottom of the nostrils, the
other, more perpendicular, running from the convexity of the
forehead to the most prominent part of the upper jaw. The
angle which the latter, – the proper facial line, makes with the
former, is greatest in the human subject, from the comparative
smallness of the brain and the great developement of the mouth
and nose in brutes. In the human adult this angle is about
from 65° to 85°; in the orang-outang about from 55° to 65°;
in some quadrupeds 20°; and in the lower classes of vertebral
animals it entirely disappears.

Neither is it to be regarded as an exact measure of the under-
standing, for persons of great intellect may have a prominent
[Seite 431] mouth; it shows merely the projection of the forehead, while the
cranium and brain may vary greatly in size in other parts;
three-fourths of quadrupeds, whose crania differ extremely in
other respects, have the same facial angle; great amplitude of
the frontal sinuses, as in the owl and hog, without any increase
of brain, may diminish it, and for this reason Cuvier draws the
facial line from the internal table of the frontal bone.

In proportion as the face is elongated, the occipital foramen
lies more posteriorly; in man consequently it is most forward.
While in man it is nearly in the centre of the base of the cra-
nium, and horizontal, and has even sometimes its anterior mar-
gin elevated; in most quadrupeds it is situated at the extremity
of the cranium obliquely, with its posterior parts turned up-
wards, and is in some completely vertical. On this difference
of situation, Daubenton founded his occipital angle.* He drew
one line from the posterior edge of the foramen to the lower edge
of the orbit, and another, in the direction of the foramen, passing
between the condyles and intersecting the former. According to
the angle formed, he established the similarity and diversity of
crania. The information derived from it in this respect is very
imperfect, because it shows the differences of the occiput merely.
Blumenbach remarks that its variations are included between
80° and 90° in most quadrupeds which differ very essentially in
other points.

The want of the os intermaxillare has been thought peculiar
to mankind. Quadrupeds, and nearly all the ape tribe, have
two bones between the superior maxillary, containing the dentes
incisores when these are present, and termed ossa intermaxillaria,
incisoria, or labialia. But it does not exist universally in them.
[Seite 432] Man only has a prominent chin: his lower jaw is the shortest,
compared with the cranium, and its condyles differ in form,
direction, and articulation, from those of any brute: (Sect. XXI.
Note F.) in no brute are the teeth arranged in such a close and
uniform series; the lower incisores, like the jaw in which they
are fixed, are perpendicular, – a distinct characteristic of man,
for in brutes they slope backwards with the jaw bone; the canine
are not longer than the rest, nor insulated as in monkeys; the
molares differ from those of the orang-outang and of all the genus
simia by their singularly obtuse projections.

The slight hairiness of the human skin in general, although
certain parts, as the pubes and axillae, are more copiously fur-
nished with hair than in brutes; the omnivorous structure of the
alimentary canal (Sect. XXI. Note E); the curve of the vagina
corresponding with the curve of the sacrum formerly mentioned,
page 428) preventing woman from being, as brute females are,
retromingent; the peculiar structure of the human uterus and
placenta; the length of the umbilical chord and the existence of
the vesicula umbilicalis until the fourth month; together with the
extreme delicacy of the cellular membrane; are likewise structural
peculiarities of the human race. The situation of the heart lying
not upon the sternum, as in quadrupeds, but upon the diaphragm,
on account of our erect position, – the basis turned not, as in
them, to the spine, but to the head, and the apex to the left
nipple; the absence of the allantois, of the panniculus carnosus,
of the rete mirabile arteriosum, of the suspensorius oculi; and
the smallness of the foramen incisivum, which is not only very
large in brutes, but generally double, though not peculiarities,
are striking circumstances.

Man only can live in every climate;* he is the slowest in
[Seite 433] arriving at maturity, and, in proportion to his size, he lives the
longest of all mammalia; he only procreates at every season,
and, while in celibacy, experiences nocturnal emissions. None
but the human female menstruates.

Man, thus distinguished from all other terrestrial beings, evi-
dently constitutes a separate species: – Fact harmonizes with the
Mosaic account of his distinct creation. For ‘“a species com-
prehends all the individuals which descend from each other, as
from a common parent, and those which resemble them as much
as they do each other;”’ and no brute bears such a resemblance
to man.*

He is subject, however, to great variety, so great indeed that
some writers have contended that several races of men must have
been originally created. We shall now examine the principal of
these varieties.

#The most generally approved division of man-
kind is that of Blumenbach. He makes five varieties; the
Caucasian, Mongolian, Ethiopian, American, and Malay. The
following are the characteristics of each.#

1. The Caucasian. The skin white; the cheeks red, – almost
a peculiarity of this variety; the hair of a nut brown, running
on the one hand into yellow and on the other into black, soft,
long, and undulating.

The head extremely symmetrical, rather globular; the fore-
head moderately expanded; the cheek bones narrow, not pro-
minent, directed downwards from the Malar process of the supe-
rior maxillary bone; the alveolar edge round; the front teeth of
each jaw placed perpendicularly.

The face oval and pretty straight; its parts moderatly distinct;
the nose narrow and slightly aquiline, or at least its dorsum
[Seite 434] rather prominent; the mouth small; the lips, especially the
lower, gently turned out; the chin full and round: – in short,
the countenance of that style which we consider the most
beautiful.

This comprehends all Europeans except the Laplanders and
the rest of the Finnish race; the Western Asiatics as far as the
Obi, the Caspian, and the Ganges; and the people of the North
of Africa.

2. The Mongolian. The skin of an olive colour; the hair
black, stiff, straight, and sparing.

The head almost square; the cheek bones prominent out-
wards; the space between the eyebrows, together with the
bones of the nose, placed nearly in the same horizontal plane
with the malar bones; the superciliary arches scarcely percep-
tible; the osseous nostrils narrow; the fossa maxillaris shallow;
the alveolar edge arched obtusely forwards; the chin somewhat
projecting.

The face broad and flattened and its parts consequently less
distinct; the space between the eyebrows very broad as well as
flat; the cheeks not only projecting outwards, but nearly glo-
bular; the aperture of the eye-lids narrow, – linear; the nose
small and flat.

This comprehends the remaining Asiatics, except the Malays
of the extremity of the Transgangetic peninsula; the Finnish
races of the North of Europe, – Laplanders, &c.; and the Esqui-
maux diffused over the most northern parts of America from
Bhering’s Strait to the farthest habitable spot of Greenland.

3. Ethiopian. The skin black; the hair black and crisp.

The head narrow, compressed laterally; the forehead arched;
the malar bones projecting forwards; the osseous nares large;
the malar fossa behind the infra-orbitar foramen deep; the jaws
lengthened forwards; the alveolar edge narrow, elongated,
more elliptical; the upper front teeth obliquely prominent; the
lower jaw large and strong; the cranium usually thick and
heavy.

The face narrow and projecting at its lower part; the eyes
[Seite 435] prominent; the nose thick and confused with the projecting
cheeks; the lips, especially the upper, thick; the chin some-
what receding.

The legs in many instances bowed.

This comprehends the inhabitants of Africa; with the excep-
tion of those in the northern parts, already included in the Cau-
casian variety.

4. The American. The skin of a copper colour; the hair
black, stiff, straight, and sparing.

The forehead short; the cheek bones broad, but more arched
and rounded than in the Mongolian variety, not, as in it, angular
and projecting outwards; the orbits generally deep; the fore-
head and vertex frequently deformed by art; the cranium usually
light.

The face broad, with prominent cheeks, not flattened, but
with every part distinctly marked if viewed in profile; the eyes
deep; the nose rather flat, but still prominent.

This comprehends all the Americans excepting the Esquimaux.

5. The Malay. The skin tawny; the hair black, soft, curled,
thick, and abundant.

The head rather narrow; the forehead slightly arched; the
parietal bones prominent; the cheek bones not prominent; the
upper jaw rather projecting.

The face prominent at its lower part; not so narrow as in
the Ethiopian variety, but the features, viewed in profile, more
distinct; the nose full, broad, bottled at its point; the mouth
large.

This comprehends the inhabitants of the Pacific Ocean, of
the Marian, Philippine, Molucca, and Sunda, isles, and of the
peninsula of Malacca.

General Remarks. The colour of the hair thus appears some-
what connected with that of the skin, and the colour of the iris
is closely connected with that of the hair. Light hair is common
with a white and thin skin only, and a dark thick skin is usually
accompanied by black hair; if the skin happens to be variegated,
[Seite 436] the hair also is variegated; with the cream-white skin of the
albino,* we find hair of a peculiar yellowish white tint; and,
where the skin is marked by reddish freckles, the hair is red.
When the hair is light, the iris is usually blue; when dark, it is
of a brownish black; if the hair loses the light shade of infancy,
the iris likewise grows darker, and when the hair turns grey in
advanced life, the iris loses much of its former colour; the
albino has no more colouring matter in his chorioid or iris than
in his skin, and they therefore allow the redness of their blood
to appear, the latter being of a pale rose colour and semi-pel-
lucid, the former, from its greater vascularity, causing the pupil
to be intensely red; those animals only whose skin is subject to
varieties, vary in the colour of the iris; and if the hair and skin
happen to be variegated, the iris is observed likewise variegated.

[Seite 437]

The Caucasian variety of head, nearly round, is the mean of
the rest, while the Mongolian, almost square, forms one extreme,
having the American intermediate, and the Ethiopian the other
extreme, having the Malay intermediate, between it and the
Caucasian.

The Caucasian variety of face is also the mean, while the Mon-
golian and American, extended laterally, form one extreme, and
the Ethiopian and Malay, extended inferiorly, constitute the
other. In the first of each extreme, viz. the Mongolian and
Ethiopian, the features are distinct, while in the second, viz. the
American and Malay, they are somewhat blended.

Although this division of mankind is well founded and ex-
tremely useful, it is liable, like every artificial division of natural
objects, to many exceptions. Individuals belonging to one
variety are not unfrequently observed with some of the charac-
teristics of another;* the characteristics of two varieties are
[Seite 438] often intimately blended in the same individual (indeed all the
four varieties run into each other by insensible degrees);* and
[Seite 439] instances continually occur of deviation in one or more parti-
culare from the appearances characteristic of any variety:* so
that the assemblage rather than individual marks must frequently
be employed to determine the variety.

Particular Remarks. The Caucasian variety is pre-eminent
in all those mental and corporeal particulars which distinguish
man from brutes. It is to the two sexes of this variety that
Milton’s lines apply, –

‘“For contemplation he and valour formed;’
‘For softness she and sweet attractive grace.”’

The cranium is very capacious, the area of the face bears to
its area but a proportion of one to four, and projects little or not
at all at the lower parts: the intellectual faculties of its indi-
viduals are susceptible of the highest cultivation, while the senses of
smelling, hearing, and seeing, are much less acute than in dark
nations. Philosophy and the fine arts flourish in it as in their
proper soil: to it revelation was directly granted.

The Ethiopian variety when instructed by the Caucasian has
produced instances of mental advancement great indeed, but
inferior to what the latter is capable of attaining. ‘“There
scarcely ever,”’ says Hume, ‘“was a civilized nation of that com-
plexion, nor even an individual, eminent either in action or spe-
culation. No ingenious manufactures amongst them, no arts,
no sciences. On the other hand, the most rude and barbarous
of the whites, such as the ancient Germans, the present Tartars,
have still something eminent about them, in their valour, form
of government, or some other particulars.”’ Blumenbach, how-
ever, possesses English, Dutch, and Latin poetry written by dif-
ferent negroes, and informs us that, among other examples of
distinguished negroes, a native of Guinea, eminent for his inte-
grity, talents, and learning, took the degree of doctor in philo-
[Seite 440] sophy at the University of Wittenberg, and that Lislet of the isle
of France was chosen a corresponding member of the French
Academy of Sciences. ‘“Provinces of Europe,”’ says he, ‘“might
be named, in which it would be no easy matter to discover such
good writers, poets, philosophers, and correspondents of the
French Academy; and on the other hand, there is no savage
people which have distinguished themselves by such examples of
perfectibility, and even capacity for scientific cultivation, and
consequently, that none can approach more nearly than the negro
to the polished nations of the globe.”’* This mental inferiority
is attended of course by a corresponding inferiority of the brain.
The circumference, diameters, and vertical arch of the cranium
being smaller than in the European, and the forehead particu-
larly being narrower and falling back in a more arched form,
the brain in general, and particularly those parts which are the
organs of intellect properly so called, must be of inferior size.
The orbits, on the contrary, and the olfactory and gustatory or
rather masticatory organs being more amply evolved, the area of
the face bears a greater proportion to the area of the skull, – as
1. 2. to 4.; the proportion is greater in the orang-outang, and in
the carnivora nearly equal.§ The senses here situated, as well
as that of hearing, are astonishingly acute, though not only in
this but also in the three following varieties, and the corres-
ponding nerves, at least the first, fifth, and facial, of great size.ǁ

[Seite 441]

The ossa nasi lie so flatly as to form scarcely any ridge; the
face, as we have formerly seen, projects considerably at its lower
part;* the lower jaw is not only long but extremely strong; the
chin not only not prominent but even receding, and the space
between it and the lower teeth is small, while that between the
upper teeth and the nose is large; the meatus auditorius is nearer
the occiput, – more remote from the front teeth than in the Euro-
pean; the foramen magnum occipitale lying farther back, the
occiput is nearly in a line with the spine; the body is slender,
especially in the loins and pelvis, whose cavity likewise is small;
the length of the fore-arms and fingers bears a large proportion
to that of the os humeri; the os femoris and tibia are more
[Seite 442] convex, and the edge of the latter, according to a remark of
Mr. Fyfe of Edinburgh, very sharp; the calves are placed high;
the os calcis instead of forming an arch is on a line with the
other bones of the foot, which is of great breadth; the toes are
long; the penis large and frequently destitute of fraenum. Mr.
White, from whom many of these remarks are derived, describes
the testes and scrotum as small; the skin is thicker,* and,
finally, the term of life generally shorter, than in Europeans.

Nearly all these facts demonstrate rather a less distance of the
Negro than of the European from the brute creation. But with an
inferiority to the Caucasians so slight if compared with his immense
superiority over the most intelligent brutes, so insensibly running
into the Caucasian and all the other varieties, so liable to innu-
merable diversities of conformation as well as bearing some re-
semblance to brutes, and so certainly bearing no more resemblance
to them in some points nor so much in others as many tribes of
other varieties, the poor negro might justly class those of us who
philosophically view him as merely a better sort of monkey or
who desire to traffic in his blood, not only below himself but be-
low apes in intellect and below tigers in feeling and propensity.

‘“Indica tigris agit rabida cum tigride pacem’
‘Perpetuam. Saevis inter se convenit ursis.”’

The Malays have but little hair upon the chin and possess a
great developement of the parts of the head above the ears.

The Mongolians are remarkably square and robust; their
shoulders high; their extremities short and thick.

The Americans have small hands and feet, and are nearly des-
titute of beard. Shorter in the forehead than the Mongolians,
they have not so great intellectual distinction.

[Seite 443]

Not only have the five varieties their distinctive characteristics,
but the different nations comprehended in each variety have each
their peculiarities, both mental and corporeal: among the Cau-
casians, for example, the Germans, French, Spaniards, and Eng-
lish are extremely different from each other. Nay, the provinces
of the same country differ, and the families of the same pro-
vince, and, in fact, every individual has his own peculiar coun-
tenance, figure, constitution, form of body, and mental cha-
racter.

A question here presents itself. – Are the differences among
mankind to be ascribed to the influence of various causes upon
the descendants of two, – or of more, but all similar, primary
parents; – or to original differences in more than two primary
parents? If considerations à priori, analogical and direct facts,
and the history of mankind, corroborate in conjunction the first
supposition, there will be no necessity to have recourse to the
bolder second, nor to the third – the boldest of the three.

On the point before us the Bible speaks positively and clearly,
without the possibility of various interpretation or corruption of
the text, and not only in the account of the creation, but inci-
dentally in many other places.* It is delightful to find nature
[Seite 444] and history investigated already so far as to harmonise with the
[Seite 445] statement of holy writ, but I shall of course detail the arguments
quite independently of this consideration.*

A priori, I think, the universal simplicity of nature’s causes
would induce us to imagine that, as, if the varieties among us
are accidental, two individuals were evidently sufficient for the
production of the rest of mankind, no more than two were ori-
ginally created. Nor can I conceive it possible to deduce a con-
trary presumptive argument from the length of time during
which immense portions of the earth must have thus remained
unpeopled. One of nature’s objects seems the existence of as
much successive life as possible, whether animal or vegetable,
throughout the globe. For this purpose every species of animal
and vegetable possesses an unlimited power of propagation, ca-
pable of filling the whole world, were opportunity afforded it.
The opportunities of exertion are indeed very scanty, compared
[Seite 446] with the power: climate, soil, situation, may be unfavourable;
one vegetable, one animal, stands in the way of another; even
the impediments to the increase of some, act through them as
impediments to others. The incessant tendency of the power
of multiplication to exert itself, seizes every opportunity the mo-
ment it is presented, and thus, though every living object has
a fixed term of existence and may be carried off much earlier
by innumerable circumstances, all nature constantly teems with
life.* The slow increase of mankind could not interfere with
this apparent object of nature; the deficiency of our race must
have invariably been fully compensated by the opportunities
which it afforded for the multiplication of other existences: for
that man alone was not designed to enjoy the earth, is shown
by the vast tracts of land still but thinly peopled. The infinitely
rare opportunities afforded for the maturity of the intellectual
and moral powers born with every human being, may afford still
greater surprise than the extent of country unoccupied by man.
After all, the great length of life in the early periods of the
world must have contributed so much to man’s multiplication
that, if food was sufficiently supplied, he might very speedily
have covered the earth.

[Seite 447]

Analogical and direct facts lead us to conclude that none of
the differences among mankind are so great as to require the
belief of their originality.

Animated beings have a general tendency to produce offspring
resembling themselves, in both mental and corporeal qualities.

‘“Fortes creantur fortibus et bonis;’
‘“Est in juvencis, est in equis patrum’
‘“Virtus: nec imbellem feroces’
‘“Progenerant aquilae columbam.”’*

An exception occasionally occurs, much more frequently in-
deed in the domestic than the wild state, – the offspring differs
in some particular from the parents; and by the force of the
general tendency transmits to its offspring its own peculiarity.
By selecting such examples, a breed peculiar in colour, figure,
the form of some one part, or in some mental quality, may be
produced. Thus, by killing all the black individuals which appear
among our sheep and breeding from the white only, our flocks
are white; while, by an opposite practice pursued in some
countries, they are black: thus a ram accidentally produced on
a farm in Connecticut, with elbow-shaped fore-legs and a great
shortness and weakness of joint indeed in all four extremities,
was selected for propagation, and the ἁγκών breed, unable to
climb over fences, is now established: thus some breeds of
hares have horns like the roebuck: the Dorking fowl has two
hind claws; and fowls indeed are bred in every conceivable
variety. Individuals, distinguished from others by no greater
[Seite 448] differences than those which thus spring up accidentally, cannot
be supposed to belong to a separate species. Upon the compa-
rison of these differences depends the analogical argument first
employed by Blumenbach. Finding the ferret (mustela furo) to
differ from the pole cat (m. putorius) by the redness of its eyes,
he concludes it is merely a variety of the same species, because
instances of this deviation are known to occur accidentally in
other animals; but he concludes the African elephant is of a
[Seite 449] species distinct from the Asiatic, because the invariable difference
of their molar teeth is of a description which naturalists have
never found accidental. Now there exist among mankind no
differences greater than what happen occasionally in separate
species of brutes.

The colours of the animals around us, horses, cows, dogs,
cats, rabbits, fowls, are extremely various, – black, white, brown,
grey, variegated.

The hair of the wild Siberian sheep is close in summer, but
rough and curled in winter;* sheep in Thibet are covered with
the finest wool, in Ethiopia with coarse stiff hair; the bristles
of the hog in Normandy are too soft for the manufacture of
brushes; goats, rabbits, and cats of Angouri, in Anatolia,
have very long hair, as white as snow and soft as silk.§

The head of the domestic pig differs as much from that of the
wild animal, as the Negro from the European in this respect;ǁ
so the head of the Neapolitan horse, denominated ram’s head on
account of its shape, from that of the Hungarian animal, re-
markable for its shortness and the extent of its lower jaw;** the
cranium of fowls at Padua is dilated like a shell and perforated
by an immense number of small holes;†† cattle and sheep in
some parts of our own country have horns, in others not; in
Sicily sheep have enormous horns;‡‡ and in some instances this
animal has so many, as to have acquired the epithet polyceratous.

The form of other parts is no less various. In Normandy,
pigs have hind-legs much longer than the fore;§§ at the Cape of
Good Hope, cows have much shorter legs than in England;ǁǁ
the difference between the Arabian, Syrian, and German, horses
[Seite 450] is sufficiently known; the hoofs of the pig may be undivided,
bisulcous, or trisulcous.

These are regarded by naturalists as but accidental varieties,
yet they equal or surpass the varieties existing among mankind.
We are consequently led by analogy to conclude, that the dif-
ferences of nations are not original but acquired, and impose no
necessity for believing that more than one stock was at first
created.

Direct facts harmonise with this conclusion. All races run
insensibly one into another, and therefore innumerable interme-
diate examples occur where the distinction between two varieties
is lost. Again, no peculiarity exists in any variety which does
not show itself occasionally in another. Many instances of these
facts have been already related (page 437, note *). The diffi-
culty of regarding the negro as of the same stock with ourselves
vanishes on viewing these circumstances and on reflecting that
he and ourselves are two extremes, one of which may have
sprung from the other by means of several intermediate devia-
tions, although experience may not justify us in supposing any
single deviation of sufficient magnitude.* Lastly, both the males
[Seite 451] and females of all the varieties breed together readily and in per-
petuity,* – an assertion which cannot be made in regard to any
different species of brutes.

The cause of the differences of our species has been more or
less sought for in climate, alone or in conjunction with other
external circumstances, by Aristotle, Hippocrates, Cicero, Pliny,
Plutarch, Galen, nearly all the Greek and Roman historians and
poets, Montaigne, Montesquieu, Buffon, Zimmerman, Blumen-
bach, Dr. Smith of America, &c. Lord Kaimes has denied the
power of these circumstances to produce the diversities of either
mind or body; and Hume has expressly written an essay to
prove the insufficiency of climate with respect to the varieties
of national character. Now the intensity of light unquestionably
affects the colour of the surface, although not to the degree of
Ethiopian blackness; heat the texture and growth of the hair;
and quantity of nourishment the size. But the effects of these
circumstances are superficial, even on animals necessarily less
protected against their influence than man. The skulls of
foxes belonging to northern regions are not different from
those of France or Egypt: the tusks of the elephant, and
the horns of the stag and rein deer, may acquire a larger
size when the food is more favourable to the production
of ivory or horn, but the number and articulations of the
[Seite 452] bones, and the structure of the teeth, remain unaltered.* Nor
are these changes, any more than those induced by mecha-
nical means, as pressure, division, &c. transmitted to the off-
spring: the child of the most sunburnt rustic is born equally
fair with other children; even all the children among the Moors
are born white and acquire the brown cast of their fathers only
if exposed to the sun; although the Jews have most religiously
practised the rite of circumcision from the days of Abraham,
their foreskin still remains to be circumcised. Were it there-
fore true that all dark nations are the inhabitants of hot climates,
as the confined knowledge of the antients justified them in be-
lieving, it would still be untrue that the change effected, for in-
stance, in the colour of the parent’s skin, had descended to the
offspring. But modern discovery has made us acquainted with
light nations, inhabiting the warmest regions, with dark nations
inhabiting the coldest, and with others of various shades of co-
lour although in the same climate.§ Many protected parts are
[Seite 453] os black as those which are exposed. Nor are the varieties of
mankind more dependent upon the varieties of food.

[Seite 454]

With civilisation and barbarism, however, they appear certainly
connected. We should beforehand be inclined to imagine that
the most excellent developement of every animated species would
be effected where all its wants were best supplied, its powers all
duly called forth, and all injurious or unpleasant circumstances
least prevalent: and vice versa. Every one knows the effect of
cultivation in the vegetable kingdom. But experience teaches us
that no change brought about in an animal after birth can be
transmitted to the offspring: the causes of change in a species
must therefore operate, not by altering the parents, but by dis-
posing them to produce an offspring more or less different from
themselves. (Such is Mr. Hunter’s view of the question,* and
it is certainly confirmed by every fact.) Uncivilised nations ex-
posed to the inclemency of the weather, supported by precarious
and frequently unwholesome food, and having none of the dis-
tinguishing energies of their nature called forth, are generally
dark coloured and less distant from brutes in conformation;
[Seite 455] while those who enjoy the blessings of civilisation, i.e. good
food and covering, with mental cultivation and enjoyment, ge-
nerally acquire in the same proportion the Caucasian character-
istics. The different effects of different degrees of cultivation,
says Dr. Smith, ‘“are most conspicuous in those countries in
which the laws have made the most complete and permanent di-
vision of ranks. What an immense difference exists in Scotland
between the chiefs and the commonalty of the highland clans.
If they had been separately found in different countries, the phi-
losophy of some writers would have ranged them in different
species. A similar distinction takes place between the nobi-
lity and peasantry of France, Spain, of Italy, of Germany. It
is even more conspicuous in eastern nations, where a wider dif-
ference exists between the highest and the lowest classes in so-
ciety. The naires or nobles of Calicut, in the East Indies, have
with the usual ignorance and precipitancy of travellers been pro-
nounced a different race from the populace; because the former,
elevated by their rank, and devoted only to martial studies and
achievements, are distinguished by that manly beauty, and ele-
vated stature so frequently found with the profession of arms;
especially when united with nobility of descent; the latter poor
and laborious, and exposed to hardships without the spirit or
the hope to better their condition, are much more deformed and
diminutive in their persons, and in their complexion much more
black. In France, says Buffon, you may distinguish by their
aspect not only the nobility from the peasantry, but the superior
orders of nobility from the inferior, these from citizens, and citi-
zens from peasants.”’ – ‘“The field slaves in America,”’ continues
Dr. Smith, ‘“are badly clothed, fed, and lodged, and live in
small huts on the plantations, remote from the example and
society of their superiors. Living by themselves, they retain
many of the customs and manners of their ancestors. The
domestic servants, on the other hand, who are kept near the
persons, or employed in the family of their masters, are treated
with great lenity, their service is light, they are fed and clothed
[Seite 456] like their superiors, they see their manners, adopt their habits,
and insensibly receive the same ideas of elegance and beauty.
The field slaves are in consequence slow in changing the aspect
and figure of Africa. The domestic servants have advanced far
before them in acquiring the agreeable and regular features, and
the expressive countenance of civilised society. The former are
frequently ill shaped, they preserve in a great degree the African
lips, and nose and hair. Their genius is dull, and their counte-
nance sleepy and stupid. The latter are straight and well pro-
portioned, their hair extended to three or four, sometimes even
to six or eight inches: the size and shape of their mouth hand-
some, their features regular, their capacity good, and their look
animated.”’*

Dr. Prichard has ‘‘been assured by persons who have resided
in the West Indies, that a similar change is very visible among
the Negro slaves of the third and fourth generation in those
islands, and that the first generation differs considerably from the
natives of Africa.’’

The South Sea Islanders, who appear to be all of one family,
vary according to their degree of cultivation. The New Zea-
landers, for example, are savages and chiefly black; the New
Hollanders are half civilised and chiefly tawny; the Friendly
Islanders are more advanced and are not quite so dark, several
are lighter than olive colour, and hundreds of European faces are
found among them.

The people of Otaheite and the Society isles are the most
civilised and the most beautiful: the higher orders among them
have a light complexion and hair flowing in ringlets; the lower
orders, less cultivated, are less pleasing.

‘“The same superiority,”’ says Captain King, ‘“which is ob-
[Seite 457] servable in the Erees (nobles) throughout the other islands, is
found also here (Owyhee). Those whom we saw, were, without
exception, perfectly well formed; whereas the lower sort, besides
their general inferiority, are subject to all the variety of make and
figure that is seen in the populace of other countries.”’*

Climate, however, has not been shewn to have no effect: but
its power, being in itself not very considerable, cannot be strongly
manifested when opposed. In fact, a diminution of the sun’s
influence does dispose to the production of light varieties: the
inhabitants of hilly situations are, caeteris paribus, fairer than the
people below, and persons of the same tribe and degree of civi-
lisation lighter in the northern parts of Europe and Asia than
those in the more Southern; whiteness, too, is very common in
the north among animals which nearer the equator are variously
coloured; a pair of brown mice kept in a dark place are said to
generate a white offspring.

Perfection, in other words, the highest compatible point of
utility or agreeableness, or of both, is nature’s universal aim in
her productions, but it is in general obtained slowly, and the
more so in proportion to the excellence or degree of the qualities
to be perfected. Animals and vegetables have to pass one period
before they burst into birth, and another before their full powers
and proportions are reached; and man, whose perfections are
very excellent, arrives at his acme very late.

It is in this respect with species as with individuals, – their
improvement is gradual.

In conformity with such observations, some suppose that all
mankind were once so far below the excellence of which they
are susceptible, – that this was to be acquired so slowly, that the
Caucasian variety once did not exist. They support this opinion
by the remark of Mr. Hunter, – that the changes of colour in
[Seite 458] brutes are always from the darker to the lighter shades,* by
occasional instances of individual blacks turning permanently
white, whereas individual whites have rarely been known to turn
black, and by the asserted probability of the most ancient
people of the earth, from whom Europeans must be descended,
having been genuine Ethiopians or Negroes.

[Seite 459]

The history of mankind supports the same inference as consi-
derations à priori and analogical and direct facts. All the na-
[Seite 460] tions of the earth appear to have branched forth from one quarter.
Dr. Prichard has traced them with great learning and judgment,
[Seite 461] and, as the subject has not been made by myself a matter of ori-
ginal research and is far too extensive to be handled here as it
[Seite 462] deserves, I must refer to his work which is both the most recent
and the best, contented with simply inserting his conclusion,
[Seite 463] which is the same as Bryant’s, although founded on different
principles.

‘“The countries bounded on the east and west by the Ganges
and the Nile, on the North by the Caspian lake, and the moun-
tainous ridges of Paropamisus and Imaus, and on the south by
the Erythraean sea, or Indian ocean, appear to have been the
region in which mankind first advanced to civilization. It is
highly probable that these countries were the primitive abode of
our species, in which alone therefore it can properly be considered
as indigenous.’

‘“In the first ages, previous to the origin of the most simple
arts, while men were as yet too rude to acquire their sustenance
by hunting (or if we receive the scriptural account of the de-
luge, before the woods were filled with wild animals), they appa-
rently obtained their food chiefly by fishing along the sea shores,
or depended for a still more precarious supply on the scanty
fruits of the earth. In this state they would of necessity lead a
wandering life and extend themselves widely. Different tribes
of ichthyophagi or of roaming savages were scattered on each
side of the primitive region, wherever an easy progress lay open
to them, along the coast or through the woods of Africa, and
around the shores of the Indian islands, of New Guinea, and
Australasia. The descendants of these dispersed races are still
found in the same abodes nearly in their original unimproved
condition, savages and negroes, such as we have seen that the
stock of their ancestors, the primeval inhabitants of Egypt and
India, were.’

[Seite 464]

‘“These were the most ancient colonies which emigrated into
the distant parts of the earth. Accordingly they exhibit no affi-
nities with the central nations in their languages, manners, or
superstitions. For they went forth when language was as yet
imperfectly formed, before manners had acquired any peculiar
character, and previous to the age of idolatry.’

‘“The condition of mankind in their primeval seats improved.
They became hunters, and afterwards shepherds. Sabaism, or
the worship of the heavenly bodies, now prevailed among them.
Some tribes of hunters and perhaps of shepherds, ascended the
chain of Paropamisus, and spread themselves gradually over the
high central plains of Asia, on one side into Siberia and Scan-
dinavia, and on the other into Kamtschatka, and through the
adjacent and probably then connected continent of America.
These are the Mongoles and other similar races whom we have
traced through Asia and the north of Europe, and the primitive
inhabitants of the New World. In the languages of these na-
tions, though much diversified and very imperfect in structure,
a certain degree of affinity may be clearly marked. In their
superstitions, vestiges remain of the primitive Sabaism, even in
their more distant settlements. Their physical characters re-
semble. In other particulars proofs may be collected in many
remote regions of the common orgin of these races.’

‘“Meanwhile agriculture was invented in Asia, and the divi-
sion of labour connected with the institution of casts, which
seems to have extended through all the primitive regions, gave a
new character to human society. The establishment of a go-
verning or military class, and of a sacerdotal class, gave birth to
political order. The priests mingling allegory and fable with
the early Sabaism, and with the relics of genuine theism and true
historical tradition, which had probably been preserved in a few
families, formed a complex system of mythology. The myste-
ries were invented. Philosophy began to be cultivated, and a
more perfect language was formed.’

‘The Celtae under their Druids, a branch of the eastern hierar-
[Seite 465] chy, advanced into the furthest west, where perhaps some ves-
tiges of previous colonists may be found. They carried with them
the mysteries, the doctrine of metempsychosis, the rites of po-
lytheism, the philosophy and the language of the east.’

‘“The Pelasgian and Thracian races established themselves in
Asia Minor and passed the Hellespont into Thrace. The former
colonized Greece and Italy; the latter passed to the northward
of the Danube into the Dacian or Getic country. Tribes of this
nation wandered at a later period through the forests of Germany,
where they multiplied and encroached upon the Celtae. Lastly
the Medes, delighting in their herds of horses, advanced through
the Euxine borders into Scythia and Sarmatia.’

‘“That all these nations, the Celtae, the Pelasgi, the Goths
and the Sarmatae were comparatively late colonists from Asia,
we may safely assert, when we consider the strong affinities dis-
coverable in their systems, in their religious rites and doctrines,
and in their dialects which are clearly branches of the Sanscrit
and old Persic, and when we remark that most of them may be
traced in history still preserved from their primitive settlements
in the East.”’

Our inevitable conclusion thus coincides with the Mosaic ac-
count, – that the whole human race is the offspring of the same
parents.

THE END.


J. Barker, Printer, 4, Crane Court, Fleet Street.

Notes
*.
[Seite x]

I am unable to discover any English translation besides my
own, which was first published in 1815. – J.E.

*.
[Seite xi]

Pref. to the Institut. Medic. Leyden. Fourth edition.

*.
[Seite xii]

Pref. to the Prim. lin. Physiol. Gottingen. First edition.

*.
[Seite 1]

Thus, long ago, the author of the book generally included among the
writings of Hippocrates, Epidemic. VI. Sect. 8. § 19. said, ‘“Those things
which contain, are contained, or moved in us with force, are to be considered.”’
This celebrated passage gave origin to the excellent work of Abr. Kaau Boer-
haave, entitled, ‘“Impetum faciens dictum Hippocrati per corpus consentiens.”’
LB. 1745. 8vo.

*.
[Seite 2]

The great preponderance of the fluids is strikingly exemplified in an entire,
but perfectly dry, mummy of an adult Guanche, one of the original inhabitants
of the island of Teneriffe. It was sent to my anatomical museum by the illus-
trious Banks, and, though all its viscera and muscles are preserved, does not
exceed 7 1/2 lbs. in weight.

*.
[Seite 3]

J. Hunter, Treatise on the Blood, Inflammation, &c. London. 1794. 4to.

*.
[Seite 4]

They divided the body into similar or homogeneous parts, as the bones,
cartilages, muscles, tendons, &c.; and dissimilar, composed of the similar, as
the head, trunk, limbs, &c.

†.
[Seite 4]

Physiologists have variously estimated the quantity of blood in a well
formed adult. Allen, Mullen, and Abildgaard, make it scarcely more than
8 pounds; Borelli, 20; Haller, 30; Hamberger, 80; J. Keil, 100. The former
are evidently nearer the truth.

‡.
[Seite 4]

J. Martin Butt, De spontanea sanguinis separatione. Edinb. 1760. 8vo.
reprinted in Sandifort’s Thesaurus, vol. ii. J.H.L. Bader, Experimenta circa
sanguinem.
Argent. 1788. 8vo.

§.
[Seite 4]

The elements of aëriform fluids of course exist in the blood; that they are
not, however, in the elastic state, as so many physiologists formerly believed,
was clearly shewn in some experiments made by me during the year 1812, upon
other mammalia. I found that a small portion of the purest air infused into the
jugular vein, excited palpitations, drowsiness, convulsions; and if the quantity
was rather increased, even death ensued. I have detailed these experiments in
the Medic. Biblioth. vol. i. 177. The illustrious Bichat observed the same effects
in his experiments. Journal de Santé, &c. de Bourdeaux. t. ii. p. 61.

*.
[Seite 6]

J. Bostock, Medico-Chirurgical Transactions, published by the Medical
and Chirurgical Society of London.
vol. i. 1809. p. 46.

*.
[Seite 7]

G. Chr. Reichel, De sanguine ejusque motu Experimenta. Lips. 1767. 4to.
p. 27. fig. 3. g.g.

†.
[Seite 7]

Unwilling as I am to follow the example of those, who, especially in modern
times, delight in changing scientific terms, I cannot but think that the words
oxygenised and carbonised may be advantageously substituted for arterial and
venous: because arterial blood is contained in some vessels called veins, v.c.
the pulmonary and umbilical; while, on the other hand, venous blood is con-
tained in the pulmonary and umbilical arteries. In the same manner, the veins
of the chorion in the incubated egg contain arterial, the arteries, venous,
blood; – to use these expressions in their common acceptation.

‡.
[Seite 7]

Consult among others whom we shall recommend in the chapter on respi-
ration, Chr. Girtanner, Journal de Physique. August. 1790.

Fourcroy, Annales de Chimie. t. vij.

Hassenfratz, ibidem, t. ix.

J. Ferd.h. Autenreith, Experimenta et observata de sanguine praesertim
venoso.
Stuttg. 1792. 4to.

*.
[Seite 8]

By Will. C. Wells, Philos. Trans. 1797, the redness of the blood in general
is rather ascribed to the peculiar structure of the globules, and its various
degrees and changes simply to the reflection of light.

†.
[Seite 8]

Such are those spurious membranes found exuded on the surface of in-
flamed viscera, v.c. those cellular connections between the lungs and pleura
after peripneumony, and the tubes observed within the bronchiae after croup:
such also are those artificial ones called, after their inventor, Ruyschian, and
made by stirring fresh blood about with a stick.

*.
[Seite 9]

Annales de Chimie. xiii.

†.
[Seite 9]

Phil. Trans. 1818. p. 181.

‡.
[Seite 9]

Hunter on the Blood, &c.

*.
[Seite 10]

In this state the albumen of the serum is also affected, for it does not co-
agulate by heat as usual, and the whole mass of blood is thinner.

†.
[Seite 10]

View of the present State and Progress of Animal Chemistry by Jöns Jacob
Berzelius, M.D. &c. Translated by Dr. Brunnmark. 1813. p. 23. Hunter,
l.c. p. 18.

‡.
[Seite 10]

Berzelius discovers lactic acid free or combined in all animal fluids. It
was first noticed by Scheele, but is generally regarded as a combination of
acetous acid with animal matter.

§.
[Seite 10]

See Dr. Bostock’s papers in the first, second, and fourth volumes of The
Medico-Chirurgical Transactions,
and Berzelius’s in the third.

*.
[Seite 11]

Phil. Trans. 1818. p. 187.

†.
[Seite 11]

Medical Literature. p. 545.

‡.
[Seite 11]

Phil. Trans. 1819. p. 2, sq.

*.
[Seite 12]

Medico-Chirurgical Journal. 1817.

†.
[Seite 12]

Medico-Chirurgical Transactions. 1818.

*.
[Seite 13]

Hier. Dav. Gaubius, Spec. exhibens ideam, generalem solidarum c.h. par-
tium.
Lugd. Bat. 1725. 4to.

†.
[Seite 13]

Abr. Kaau Boerhaave, on the cohesion of the solids in the animal body,
Nov. Comm. Acad. Petropolit. t. iv. p. 343 sq.

‡.
[Seite 13]

The parallel and reticulated bony fibres are most striking in the radiated
margins of the flat bones, as we find these in young hcads much enlarged by
hydrocephalus. I have, in my museum, a preparataon of this kind, where in
the sphenoid angles of the parietal bones, the fibres are an inch or two in length,
distinct and delicate. The hardest parts, – the bony and vitreous portions of
the teeth, exhibit a structure similar to that which in the zeolite, malachite,
hematite, &c. all mineralogists call fibrous.

*.
[Seite 14]

Dav. Chr. Schobinger, (Praes. Hallero) De tela Cellulosae in fabrica c.h.
dignitate.
Gotting. 1748. 4to. Sam. Chr. Lucae at the end of his Observ. Anatom.
circa nervos arterias adeuntes.
Francof. 1810. 4to.

†.
[Seite 14]

Casp. Fr. Wolff, Nov. Act. Petropol. t vi. p. 259.

*.
[Seite 15]

I have treated this point at large in my work, De Generis Humani varie-
tate nativa.
p. 46. edit. 3.

*.
[Seite 16]

Récherches sur le tissu Muqueux.

*.
[Seite 17]

A host of authors on the vital powers will be found in Fr. Hildebrandt’s
Lehrbuch der Physiologie. p. 54 sq. edit. 2. 1809. To whom we may add
E. Bartel’s Systemat. Entwurf einer allgemeinen Biologie. Franckfurt. 1808:
and J.B.P.A. Lamarck’s Philosophie Zoologique. Paris. 1809. 11 vols. 8vo.

*.
[Seite 18]

‘“Life is formally nothing more than the preservation of the body in mix-
ture, corruptible indeed, but without the occurrence of corruption.”’ Stahl.

‘“What we call life is opposite to putridity.”’ J. Junker.

*.
[Seite 20]

That Haller and Theoph. de Bordeu – the chief writers on the mucous tela,
did not form a just conception of this vital power, is evident from the latter’s
Récherches sur le Tissu Muqueux. Par. 1767. 8vo; and from the dissertation of the
former on Irritability in the Dictionnaire Encyclopédique d’Yverdun. T. xxv.

†.
[Seite 20]

Haller, De Partibus Corp. Hum. irritabilibus in the Nov. Comm. Soc. Reg.
Scient.
Gotting. T. iv.

‡.
[Seite 20]

I have spoken of these at large both in my treatise De Iridis Motu. 1784;
and my programma De Vi Vitali sanguini deneganda. 1795.

*.
[Seite 21]

On the vita propria of the absorbent vessels consult Seb. Justin. Brug-
mans, De Causa Absorptionis per Vasa Lymphatica. Lugd. Bat. 1795. 8vo.

On the peculiar vital properties of the arteries consult Chr. Kramp, Kritik
der Praktischen Arzneikunde.
Leipzig. 1795. 8vo.

Many of the phenomena now mentioned are ascribed by others to an orgasm,
to use an old expression, struggling from the centre to the circumference, and
lately designated vital turgor.

†.
[Seite 21]

Fouquet, Dictionnaire Encyclopédique de Paris. T. xv. Art. Sensibilité.

‡.
[Seite 21]

Consult C. Fr. Kielmeyer, Uber die Verhältnisse der organischen Kräfte
[Seite 22] in der Reihe der verschiedenen Organisationen.
1793. 8vo. H.F. Link, Uber
die Lebenskräfte in naturhistorischer Rücksicht.
Rostock. 1795. 8vo.

*.
[Seite 22]

See Abildgaard, Acta Reg. Soc. Med. Havniens. T. i.

*.
[Seite 23]

v. c. Dan. Bernouilli, De Respiratione. Basil. 1721.

[Seite 24]

‘“Respiration supplies a very subtle air, which, when intimately mixed with
the blood, greatly condensed, conveyed to the moving fibres, and allowed by
the animal spirits to exert its powers, inflates, contracts, and moves the muscles,
and thus promotes the circulation of fluids and imparts motion to mobile
parts.”’

*.
[Seite 24]

Laur. Bellini, De Sanguinis Missione. p. 165–193.

Sylvest. Douglas, De Stimulis. Lugd. Bat. 1766.

*.
[Seite 25]

Montesquieu, De l’Esprit des Lois. T. ii. p. 34. London. 1757. 8vo.

†.
[Seite 25]

J. Casp. Hirzel, De Animi laeti et erecti efficacia in corpore sano et aegro.
Lugd. Bat. 1746.

‡.
[Seite 25]

Called Le Tact ou le Gout particulier de chaque Partie, by Theoph. de
Bordeu, Recherches Anatomiques sur les Glandes. p. 376 sq.

§.
[Seite 25]

Sam. Farr, on Animal Motion. 1771. 8vo. p. 141.

J. Mudge’s Cure for a recent catarrhous Cough. Edit. 2. 1779. 8vo.
p. 238.

Gilb. Blane, On Muscular Motion. 1788. 4to. p. 22.

J.L. Gautier, De irritabilitatis notione, &c. Hal. 1793. 8vo. p. 56.

ǁ.
[Seite 25]

J.H. Rahn, De Causis Physicis Sympathiae. Exerc. i.–vii. Tigur. from
1786. 4to.

Sylloge selectiorum opusculor. de mirabili sympathia quae partes inter di-
versas c.h. intercedit.
Edited by J.C. Tr. Schlegel. Lips. 1787. 8vo.

*.
[Seite 26]

G. Egger (the author Lawr. Gasser), De consensu nervorum. Vindob.
1766. 8vo.

†.
[Seite 26]

J.G. Zinn’s Observations on the different Structure of the Human Eye
and that of Brutes. Diss. ii. 1757. Comment. Soc. Reg. Scient. Gotting.
antiquiores.
T. i.

‡.
[Seite 26]

Consider the constant sympathy of heat between certain parts of some
animals, v.c. of the hairs with the fauces, in variegated rabbits, sheep, dogs, &c.;
of the feathers with the covering of the bill and feet in varieties of the domestic
duck. That many such instances are not referrible to the influence of nerves,
I contended in my Comm. de motu iridis. p. 12 sq. and also in my work de
generis humani varietate nativa,
p. 364 sq.

§.
[Seite 26]

Innumerable pathological phenomena will be found explained by this sym-
pathy in S. Th. Soemmerring’s De Morbis Vasorum Absorbentium Diss. quae
praemium retulit.
Francof. 1795. 8vo.

*.
[Seite 28]

Hence after death, even in young subjects full of juices, the back, loins,
and buttocks, having for some time lost their vital tone, are, if the body is
supine, depressed and flattened by the superincumbent weight, which now is
not resisted: this appearance I regard among the indubitable signs of death.

†.
[Seite 28]

Treatise on the Blood, &c. Introduction.

‡.
[Seite 28]

Anatomie Générale. T. i. p. 183 sq.

*.
[Seite 29]

Consult Whytt, Observations on Nervous Diseases. Ch. i.

†.
[Seite 29]

Sir Gilbert Blane, Medical Logic. p. 61.

‡.
[Seite 29]

Consult Bichat, Traité des membranes.

*.
[Seite 30]

Consult Alex. Chrichton, Inquiry into the nature and origin of mental
derangement, comprehending a concise system of the Physiology and Pathology
of the human mind.
Lond. 1798. 2 vols. 8vo. Em. Kant, Anthropologie in
pragmatischer Hinsicht.
Königsb. 1798. 8vo. Chr. Meiner, Untersuchungen
über die Denkkräfte und Willenskräfte des Menschen nach Anleitung der
Erfahrung.
Gött. 1806. 2 vols. 8vo.

*.
[Seite 31]

The difference, analogy, and relation, of memory and judgment, have given
rise to various controversies. Some celebrated psychologists have included
both under the word imagination taken in its most comprehensive sense, and
have divided it into two species; memory – representing former ideas, and the
facultas fingendi – representing such ideas only as are formed by abstraction.
They again divide memory into sensitive (imagination in a stricter sense) and
intellectual.

Their facultas fingendi they also subdivide into intellectual – the more ex-
cellent; and phantasy – obeying mechanical laws. Feder, Grundsätze der
Logik und Metaphysik.
Götting. 1794. p. 20.

†.
[Seite 31]

Of this the highest prerogative of the human mind, by which man exerts
his dominion over other animals, and indeed over the whole creation, I have
fully treated in my book De Gen. Hum. Var. Nat. p. 32. ed. 3.

*.
[Seite 32]

Dugald Stewart, Outlines of Moral Philosophy. p. 10.

*.
[Seite 33]

I was convinced of this being a distinct power, upon perusing an Essay
on decision of character, written some years ago by a dissenting minister who
I dare say never thought of craniology. Essays by John Foster.

†.
[Seite 33]

A wonderful instance of this propensity is detailed in the Philos. Trans.
1677. The strength of it seems part of the national character of the Ashan-
tees. Bowditch, Mission from Cape Coast Castle to Ashantee. p. 292.

*.
[Seite 34]

The Physiognomical System of Drs. Gall and Spurzheim.

†.
[Seite 34]

Serm. i. Upon the social nature of man. Serm. ii. iii. Upon the natural
supremacy of conscience.

*.
[Seite 35]

Theod. G. Aug. Roose, Uber die Krankheiten der Gesunden. Götting.
1801. 8vo.

G. Chr. Klett, Tentamen evolvendi notionem de sanitate hominis. Wirceb.
1794. 8vo.

†.
[Seite 35]

Galen, quod animi mores corporis temperaturas sequantur.

[Seite 36]

St. J. Van. Geuns, De corporum habitudine animae hujusque virium indice ac
moderatrice.
Harderv. 1789. 4to.

*.
[Seite 36]

Galen, De sanitate tuenda. L.i.

†.
[Seite 36]

W.F. Ad. Gerresheim, De sanitate cuivis homini propria. Lugd. Bat.
1764. 4to.

‡.
[Seite 36]

Lavater, Physiognomische Fragmente. T. iv. p. 343.

W. Ant. Ficker, Comm. de temperamentis hominum quatenus ex fabrica et
structura corporis pendent.
Gotting. 1791. 4to.

J.N. Hallé, Mem. de la Soc. Médicale d’Emulat. T. iii. p. 342.

§.
[Seite 36]

To the numerous arguments by which the moderns have overthrown the
doctrine of the ancients, and proved that the temperament depends on the living
solids rather than on the nature of the blood, I may add the celebrated example
of the Hungarian sister twins, who, at the beginning of the last century, were
born united at the lower part of the back, and attained their twenty-second
year in this state. They were, as is well known, of very different temperaments,
although dissection discovered that their sanguiferous systems anastomosed so
considerably that the blood of both must have been the same.

*.
[Seite 37]

Kant, l.c. p. 257 sq.

†.
[Seite 37]

Feder, Untersuchung über den menschlichen Willen. T. ii. p. 49.

‡.
[Seite 37]

Galen, De Consuetudine.

G.E. Stahl, De consuetudinis efficacia generali in actibus vitalibus. Hal.
1700. 4to.

H. Cullen, De Consuetudine. Edinb. 1780. 8vo.

C. Natorp, De vi consuetudinis. Gott. 1808. 4to.

*.
[Seite 38]

See Platner, Quaest. physiol. p. 31; and Versuch einer Anthropologie.
T. i. p. 100, 222; and my own remarks on the bad foundation of this division,
in the preface to my Enchiridion Anat. Comparata, p. xi sq.

†.
[Seite 38]

J.J. Bernhard, Versuch einer Vertheidigung der alten Eintheilung der
Functionen, und einer Classification des organisirten Körper nach denselben.

Erf. 1804. 8vo.

*.
[Seite 39]

Treatise on Febrile Diseases. Ch. iii. Sect. 3. First Edition. 1799. Paper
read, to the Royal Med. Society of Edinburgh.
1791 or 1792, and inserted in
its Records. Essay on Opium.
1795. Edinburgh Med. and Surgical Journal.
July. 1809. p. 301 sq.

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