SCIENCE OF COMPARATIVE ANATOMY;

SHOWINO

THE GREAT IMPORTANCE OP ITS PERFECT CULTIVATION

AND ALSO

ITS UTILITY TO THOSE STUDYING THE PHYSIOLOGY OF

THE HUMAN FRAME.

Delivered at the Westminster School of Medicine.

By H. W. RUSH, M.R.C.S.

AND LECTURER ON COMPARATIVE ANATOMY

AT THE WESTMINSTER SCHOOL

OF MEDICINE.

LONDON :

PUBLISHED FOR THE AUTHOR,

and SOLD BY ALL THE MEDICAL BOOKSELLERS.

XDCCCXXXV.

London:

BRADBURY AND EVANS, PRINTERS, WHITEFRIARS.

^5CU1+-

ADDRESS

TO THE

MEDICAL PROFESSION.

It will be seen by all who read the London Medical and Sur-
gical J ouunal, published by a Mr. Renshaw of the Strand, that *
Lecture, introductory to the Science of Comparative Anatomy,
delivered at the Westminster School of Medicine, has been inserted
by him in the last number (181, vol. vii,) without the name of the

As this Lecture occupies a considerable
if °- *e ai,d is upon a science extensively cultivated

Z,,7e °f ‘he Na'"e °f «* Lectum "V sonJhal

As the Deliverer of l he Lecture in question happens to be at the

M or Te T\ PrOP"e‘°'i °f the ■ " «• recognized

Mr P i? fee S a^rIeVed at the underhanded mode in which

said Lecture^ preVent^ h'S "ame aPPearin-? a* the Author of the

A plain statement of facts, representing the trickery by which
Mr Renshw accomplished his scheme of suppressing the Name

ad a , " rerma; "°‘b? '»PP™P*t«, or, indeed, Without some
advantage to Professional Men; especially that portion of them

uXleller?f°rtUnate Gn°Ugh t0 *«i aPublist

Medical7 and S* recolIectlou of the readers of the London

ttrsKnc? ;:;"5 ““ *& =

2

The facts are these : — Mr. Rush, the author of the Lecture in
question, consented to allow it to appear in the Journal, upon the
condition that his name should be affixed to it as the author. This
Mr. Rush considered he had a perfect right to demand, from the
fact of his possessing a large portion of the copyright of the Jour-
nal : and, indeed, the affair went so far upon this understanding
that the name of Mr. Rush actually appeared affixed to the Lec-
ture in the proof sheet, — but was afterwards, (mark!) before
the numbers were struck off, expunged by a sly trick of
Mr. Renshaz £T$, who is supposed to have marched most valiantly
under the cover of the night, to the Printer’s, when he well knew
that the author would not be present, to insist upon his right to
retain his name to the Lecture, or of withdrawing it altogether
from publication in the Journal, — placed his' veto upon it, and,
both illegally and treacherously ordered the Printer to omit it ; his
motives for this procedure being simply, that a misunderstanding
had occurred a few days prior to this manly feat on the side of
Mr. Renshaw with Tegard to the conducting of the Journal,
Mr. Renshaw demanding to act as sole Editor. Yes, reader, sole
Lditor ! although not possessing a particle of medical knowledge;
and Mr. Rush, notwithstanding this presumption on his (Mr.
Renshaw’) part, insisting on having the Journal conducted by a
medical man, according to the terms in the articles of agreement.

On the motives which stimulated Mr. Renshaw to condescend to
this piece of double-dealing, Mr. Rush declines commenting, fur-
ther than to submit, that a bookseller, being at the same time,
from his own confession , too much engaged with his own trade,
cannot be the best Editor in the world for a Medical Journal,
which, before he meddled with it, had been conducted by a. phy-
sician of some eminence. The medical profession, it is not doubted,
will properly estimate Mr. Renshaw’s interference, in thus surrep-
titiously withdrawing Mr. Rush’s name from the heading
of the Lecture. That injury was intended to the profes-
sional interests of Mr. Rush must appear plain, and Mr. Rush's
motives in publishing this lecture separately are merely to neutralize
that evil intention, and at the same time to caution medioa>F men
how they place their literary reputation at the mercy of an Edit-
orial Bookseller. One word more. Mr. Rush’s Lecture is not
the first that has suffered from the mutilating propensities of this
would-be Editor, to whom the Subscribers to the Medical and
Surgical Journal are indebted for the deprivation of a portion o! a
course of Clinical Lectures bv one of our most celebrated physi-
cians, who, justly indignant at this supererogatory .raeddiing, with-
drew from the publication his able assistance and support.

H. W. RUSH,

1, Everett Street, Russell Square.

July 20, 1835.

3

Mr. Rush’s reply to Professional Men , who have
communicated with him upon the subject.

Since the before going remarks were sent to press, Mr. Rush
has received a number of letters from his professional friends, re-
questing an explanation from him with regard to the omission of
his name from the lecture in question ; some have asked him, if he
was ashamed of his name being attached, others if the lecture had
even been delivered, and again others, who, knowing in part [the
Editional pozoers of M. Renshaw, made a pretty shrewd guess,
and asked whether it was not probable or at all possible, that Mr.
Renshaw by omitting the name of the author, thought that he might
have been’considered not only Editor, and Bookseller, but also

LECTURER.

Mr. Rush can only reply, to his numerous professional friends,
by repeating the plain facts, which will be found in his public
address, and then leave the profession to judge for themselves.

In conclusion, Mr. Rush begs publicly to acknowledge phis
grateful thanks, to all those professional men, who have taken upon
themselves the trouble of enquiring into this trading'like transaction
so as to free him from those suppositions, which otherwise might
have been injurious to his reputation and character.

July , 21 f /, 1835.

LOW1S, Printer, Upper St. Martins Lane.

I

.

bn.-'

.

■

I

INTRODUCTORY LECTURE.

Gentlemen, — In presenting myself before you as Lecturer on Comparative
Anatomy, it is not my intention to launch out into the fields of rhetoric, or to
clothe the facts it will be necessary for me to explain, in a splendid mantle of
high sounding words. No, gentlemen, mine is the humbler task of a teacher,
not the arduous duty of the orator ; my aim shall be, therefore, rather utility,
than an ostentatious display of eloquence.

The science which I am about to inculcate, it is true, admits of the aid of
glowing and impassioned language, and possesses within its ample domain
beauties of no ordinary stamp : the symmetry and proportions of animated
nature, together with their nicely balanced functions, the rise and fall, the
origin and decay, of certain organs in various forms, and the proof that no par-
ticular organ is in itself essential to life. It will be my duty to show you, the
curious disposition of the various parts, not of one animated body, but of the
whole range of Hying things, whether they walk the earth, exist within its
substance, inhabit the depths of ocean, or soar in the air. It will be my duty,
I repeat, to explain to you their component parts, and to trace them from a
state of incipient development in some animals, to their full expansion in
others ; to mark out the distinctive characteristics, as well of the meanest
reptile that is scarcely seen crawling on the surface of our globe, as of the
majestic and stupendous elephant, who shakes it with his tread ; to lay open,
in short, before your eyes, the mechanism of all created beings, and introduce
you to a museum, in which whatever is endued with life, motion, and sense,
constitutes the spectacle. Gentlemen, a science which claims so wide a king-
dom, and embraces, I may say, if not innumerable, almost innumerable facts,
you will confess cannot but demand much time in its development, and that
lucid arrangement in the unfolding of it, which may' tend to render its difficul-
ties lighter, and to facilitate its acquisition. To accomplish the latter desirable
end, I propose delivering, in the course of this season, sixteen lectures, which
may be termed introductory to the science, since in them I shall not so mueh
enter into its details, as endeavour to form a striking and comprehensive out-
line of the whole, so that a fair view having been given of its extent and
bearing, the more minute and particular descriptions entered into during the

4

Mr. Hush's Introductory Lecture

next session may be better comprehended and remembered. In reflecting on
the subject, this has appeared to me to be the most eligible mode of proceeding
for when once a well-defined and intelligible picture of the aggregate has been
exhibited to the mental vision, the separated parts are more easily referred to
afterwards, and their peculiarities and distinctions better understood, and
retained in the memory. Feeling thus, gentlemen, I must claim your indul-
gence should my efforts to render clear any portion of my subject appear to
you to be unsuccessful, and I crave the boon with more confidence of its being
granted, from knowing, first, that I have exerted myself to the utmost in order
to avoid such a failure, ,and in the second place, permit me to add, from being
convinced that the generosity which ever animates such an assemblage of
worth and talent as that which I now have the honour to address, is prone to
judge favourably, where the difficulties in the execution are great, and to
condemn unwillingly.

Having said thus much, gentlemen, I now proceed to my subject, and in the
first place must endeavour to trace some of the sources from which compara-
tive anatomy or zootomy (which may be defined to be that science which
teaches the difference of structure in man and the inferior animals) derived its
origin. In attempting this, we are not left altogether to vague surmise, as
occurs in exploring the origin of most other sciences, for in the sacred writings
we are informed that the sons of our first parents offered up sacrifices of
animals, long before animal food was permitted, and in doing this a division of
the parts became necessary, since some were deemed impure and cast aside,
while others were adopted as fit for the solemnity ; proceeding on, we may
conclude that when the world became more peopled, and wars ensued, the
wounds inflicted by the coarse and barbarous weapons used, must frequently
have exposed to view the internal structures of man in a greater degree than
is the case in present times : the slaughter and division of the larger animals
occurring at the same period, could not fail to strike the beholders with some-
thing like a comparison between their parts, and those of man. As civilisation
advanced, and men became more secure in the enjoyment of their ease, new
wants arose, and embalming, as practised by the Egyptians, might have added
something to this kind of knowledge ; not, however, much, since we find, from
the writings of Herodotus, that the embalmers were obliged to draw out the
internal parts piecemeal, in order to avoid mutilating the body. Enough
nevertheless, must have been learnt in this way to demonstrate the analogy
between the structure of man and the inferior animals.

The soothsayers and augurs, whose importance among the ancients was very
great, could not have done much in the advancement of the science, for their
examinations were confined to the great cavities of such animals as they slaugh-
tered, and a simple inspection of the bowels made, from which they pretended
to extract their prophecies. In some work attributed to Hippocrates, there is
a tolerably exact parallel between the chylopoietic viscera of a man and a dog.
In the third and fourth century before the birth of our Saviour, anatomy was
certainly cultivated among the philosophers. Plato reasons on this science ;
and his cotemporary, Aristotle, undertook a natural history of the form and

5

to the Science of Comparative Anatomy.

i structure of animals, at the command of his pupil, Alexander the Great, and
seems to have illustrated his descriptions by drawings, an improvement of vast
i; utility.

Zootomy is a term which is frequently given to comparative anatomy, and,
in fact, it is the one which implies the demonstration of the science. It is so
called from 2>av, “an animal,” and repm/v, “to cut,” while, on the contrary, the
term comparative anatomy, which was given by Vicq-d’Azyr, is more intended
to express the multitude of comparisons which we shall find existing in the
structure of different animals, and was first so called from a comparison between
the organs of inferior animals, and those of the human body.

The differences that exist between what are termed the general sciences and
natural history, I shall not this evening consider to any extent, but briefly
remark, that in the former, man has some controul over the conditions of the
phenomena which he studies, but in the latter, the phenomena are not within
his grasp ; he can decompose and analyse them only by reflection and deep
meditation.

On reflection, when we consider what a variety of conditions are necessary
to animal life, we mav at once almost conceive the everlasting task in endca-
vouring to detect the phenomena which support it.

The structure of all living bodies may be termed a porous texture, by which
plates of a fibrous and solid nature, more or less flexible, intercept fluids more
or less abundant, and this is called organisation. Now none but organised
bodies are susceptible of life ; every organised body has a form peculiar to
itself, and is peculiarly adapted to its wants and habits.

The science of comparative anatomy I have said to be of very ancient
i origin, though until very lately it has not received its due cultivation. We

! observe from the oldest historical records we possess, that sacrifices of animals
were offered to the deities by the priests of the Israelites, the Egyptians, and
’ the Greeks. Moses, nearly six and thirty centuries ago, described the method

!of conducting these sacrifices among the Israelites, when calves, lambs, pigeons,
doves, &c., were offered to the Deity as an atonement for the sins of his
; people. At this ancient period, however, we must not give them credit for
more than ordinary observation, though Homer, in his poems, informs us that

I they possessed an intimate knowledge of the internal parts of many of the
lower kind of animals. They possessed undoubtedly a knowledge of the
position of the larger organs, they inspected the difference of appearance of
i the same organs in different animals ; they were able, in a word, to distinguish
' a healthy organ from one that was in a great state of disease. Their object,
j however, was not for any rational pursuit ; they merely wished to survey one

I or two of the larger organs, particularly the heart and liver, since from these
organs their signs and omens of future events were taken. Indeed it is sur-
prising that from the curiosity the internal parts of different animals must have
<j then excited, that they did not cause more acute observation ; but in those
i darkened ages, superstition and bigotry domineered over every science ; the
kings and priests, incited by artful knavery, did all in their power to check
even the means of observation.

(i

Mr. Rush's Introductory Lecture

1 lie first who appears to have examined the internal structure of the lower
animals with a scientific view, is that eccentric but acute philosopher Demo-
critus, a few hundred years before the birth of Christ. It is said, that when he
retired into the unhealthy forests of Abdera, he selected a spot under a tree,
where he was in the habit of sitting, surrounded by a number of animals for
the purpose of dissection. Hippocrates, his contemporary, here visited him in
his solitude, and acknowledges that he gained much information from the
researches of this anatomical observer. This lover of medicine (Hippocrates),
who afterwards gave much of his time to anatomical studies, describes the
brain to have been a sort of cooling apparatus, to condense the fumes arising
from other parts of the body ; but in a letter which Hippocrates received from
Democritus, the latter therein stated that the brain was the true seat of the
operations of the mind. Pythagoras and Empedocles also directed their
attention to the internal structure of animals. The Egyptian priests pos-
sessed also at a very remote period many opportunities of examining the
viscera of different animals, as in that country some of them were worshipped
as deities, and kept after death embalmed in the pyramids. We have fre-
quently from these ancient monuments many of those animals brought to
Europe in a state of high preservation. Geoffrey St. Hilaire brought, both
from Upper and Lower Egypt, mummies of various kinds of animals.
Herodotus and Diodorus Siculus have given some very interesting accounts
both of the process of embalming and of the sacrifice of animals among the
Egyptians.

Aristotle, who had every advantage afforded to him for the study of com-
parative anatomy a man could well possess, may be considered the first who
made real progress in this science. His writings prove him to have been
thoroughly acquainted with the animal machine, and to have been a man of
very great research and deep observation. Few' have been able to surpass
some of his descriptions, and even Baron Cuvier asserts that many of them
excel those given by Buffon.

From Pliny, whose works contain all the information of the age in which he
wrote, and from the few facts of comparative anatomy his works contain, we
may easily perceive the slowr progress the science made during the long interval
between these two philosophers. The science for many years, in fact, was
dwindling away ; and it wras not until the sixteenth century that it wras again
cultivated. Columbus and Aldrovandus then pointed out the importance and
practical use of this science, and opened a path for its future cultivation.
The science has, since then, been gradually developing; but it was not until
after the eloquent writings of Thembly, Rossel, and Ellis, that comparative
anatomy was made a distinct branch of science ; previous to this it had become
mingled with some of the general sciences, but more particularly human
anatomy. The countries that have most contributed to the progression of
this science are Germany and France. Why we have been so slowr in facili-
tating its progress is somewhat difficult to explain, for there is no country that
possesses more opportunities than we do. We have, in almost every part of
the world, territories of our own ; there is scarcely any part of the world that

to the Science of Comparative Anatomy. 7

we dare not penetrate ; but yet, from negligence, or for some no better cause,

iwe have been the most scanty contributors. It is true that the labours of our
countrymen have extended the boundaries of the science in, I may say, many
of its departments. We are indebted to Hewson, Douglas, and more par-
ticularly to the immortal Hunter, for unfolding the darkened veil respecting
the laws of animal organisation, and pointing out the utility of the principles of
comparative anatomy with regard to disease in the human being.

It would be tedious, though perhaps not altogether uninteresting, if I were
thus to continue and trace to the present day the men who have been keeping
this science on the march ; and otherwise, the short space of time allotted to
me would not permit my giving you even a general idea of them. I will
therefore briefly state to you that France and Germany have produced many
more valuable works and specimens than any other countries.

I have already mentioned to you one reason that caused the difficulty in
former times of pursuing this study, and I have named and given proof of its
existence. For centuries, yea, even from the creation of things to the present
day, there has always existed many foolish superstitious ideas with regard to
the dissection of the human body. It was in consequence of this that zootomy
was made a study, to throw some light, if possible, on the human frame ; never-
theless, this even was not practicable at a still more remote period, as there
existed also nearly as much superstition with regard to the dissection of some
animals. These ideas, the offspring of darkness, are received now, by a more
enlightened age, with that ridicule they deserve. The human mind is in
I a higher state of cultivation ; the stalk upon which it has been engrafted is
now become saturated with sap, which, though scanty at first, nevertheless
existed in the branch previous to its being placed upon the half-sapless trunk ;
every science is consequently striding along, and undoubtedly each will be
productive of good fruit. We cannot, indeed we must not, expect that each
stock will be equally productive. We know that amongst so many we must find
some worse than others. Some for their cultivation require a much longer
time ; others, in fact, manure them as you will, never arrive to any state of
perfection.

It is not without astonishment that we look back, and find the progress that
1 each individual science has made, and not equalling in utility the science under
our present consideration ; a study, in fact, which, putting aside the utility of
i the science, is one of the most natural, the most interesting, and the most
\ beautiful of all the general sciences- A science, unequalled, then — a science
a that will hereafter be one of the most useful to the preservation and health of
t mankind one which must always excite the curiosity of the philosopher — and
j one which, perhaps, after it has received its proper cultivation, will be the means
, of our detecting some phenomena explaining the intricacy of life. Has it not
I been hitherto the means of detecting the different actions going on in our own
<1 frame ? It is true, that the lacteals were detected in the human frame ; but
I before their discovery by Veslingius, did not Asellius for at least twelve years
j detect them in quadrupeds ? Again, was it not zootomical knowledge that led
‘ Galvani to discover galvanic action? The thoracic duct was also discovered

8

Mr. Rush's Introductory Lecture

by Eustachius in examining the viscera of a horse ; and had it not been for the
dissection of animals, would the immortal Harvey ever have discovered the
circulation of the blood ? These facts, gentlemen, will show you why an
impulse w'as given to the study ; and, in a word, it will show that the science
has relation with every other — indeed it contemplates the principles of nature’s
works.

In forming our ideas of life, it is necessary that we should observe its effects
in those bodies in which the effects are most simple and manifest. “ By thus
considering it,” says Cuvier, “ we shall be convinced that life consists in a
faculty possessed by certain corporal combinations.”— “ Life,” he adds, “ may
be considered as a vortex more or less rapid, more or less complicated, the
action of which is constant, and is always exerted on particles of the same
description. And as all the individual component particles are thus in a state
of continual mutation, constantly going and coming, we may assume that the
form of such a body is more essentially and properly its own than the
substance ; — the one is co-extensive with its existence, the other is gradually
but incessantly changing.”

As long as this motion continues, the body is called living ; when it has
ceased, the body dies, the component parts undergo decomposition, and the
body evaporates.

One of the most striking mysteries in the animal economy is the birth of
organised beings. We find them, and, in fact, observe them, developed, but
cannot detect how they are formed ; w’e trace them when attached to a body
of their own kind, but which has been developed long before them ; in this
state we acknowledge them to be germs. The point to which the germ is
attached, and even the cause which gives it an independent existence,
frequently varies ; but, without exception, it must always have a primary con-
nexion. The two extreme limits, then, of existence, are birth and death : and
if it were not that organised beings had the powrer of reproduction, there would
be an end of existence altogether. From these facts we cannot help allowing
that certain forms have been perpetuated since the origin of things, and that
every animal is capable of continuing its own race. All the individuals
belonging to any one of these forms constitute what is termed a species.
Varieties, however, are mere ramifications of the species.

All living beings are, in a certain degree, metamorphosed in the course of
their advancement to maturity ; certain parts are lost, and others more
completely and fully formed during their advancement. We find enclosed
within the skin of the caterpillar, the antennae, the wings, and all the parts of
the future butterfly. Contemporaneously with that skin disappear the jaws, the
feet, and other organs which belong not to the butterfly. The feet of the frog
lie concealed under the covering of the tadpole, and when the latter rises to
become a frog, the tail, the mouth, and the gills are no more found. The
infant, at its birth, loses the placenta and the foetal coverings ; as it gets older,
it loses almost entirely the thymus gland, and gradually is furnished with hair,
teeth, and, at a still more advanced period, with a beard ; the body augments
more in proportion than the head, the head more than the internal ear : white.

9

to the Science of Comparative Anatomy.

when the frame is fully developed, we find that the liver, the largest viscus in
•I the infant, bears a much less proportion to the other viscera than in the

i infantile state.

In taking a brief sketch of the active forces of the animal machine, I may
observe that the muscular fibre always exists where there is need for the opera-
tion of compression. The basis of this fibre is denominated by chemists fibrin ;
and it is this substance which nature has recourse to for carrying on the changes
and transmutations necessary for vegetable life. The action of these fibres is,
in part, controlled by the will, and hence called voluntary ; there are some,
however, over which the will has no power, and these are called involuntary.
Thus the muscular fibres of the intestines carry on the peristaltic motion of the
bowels, and the muscular fibres of the heart produce the incessant contractions
and dilatations of that organ.

The transmutations of the alimentary canal, which are necessary to ,
vegetative life, are carried on by means of irritation. For example, we find
the food first stimulating the glands in the mouth, there causing a secretion of
the saliva ; it then enters the stomach moistened by the saliva, and there pro-
duces another irritation, where it causes an extra secretion of gastric juice. We
now find, as it passes along into the duodenum, it becomes a still more com-
pound body, and an additional secretion then takes place. A division now
occurs ; the most nutritious goes to the support of the fabric, through the me-
dium of the lacteals, and renovates, or, as it were, re-excites both the nervous
j and circulating systems. The other portion, which is not proper for the support
of the body, is carried along the intestines by means of the peristaltic motion of
these organs, and is in fact the stimulus which causes the motion to take place
After the food has been taken into the stomach, these continual changes go on
independently of the will ; and if the animal is in a perfect state of health, is
carried on without its being conscious of it. In some animals the excrement,
instead of passing oft by the lower outlet ot the intestines, is again ejected by
the mouth ; but this takes place only in animals of the very lowest grade, and
in them there is but one opening to the intestinal canal. There are some
animals, however, in which we find the residue pass off solely by transpiration,
and this class is much more numerous than the preceding, but in them also we
have but one opening.

The circulating system, which is also intimately connected with the muscular,

1 is carried on in some animals in a much more complex form than in others ;
i some possess only a single or simple apparatus, others a double one ; again,
we find some that are furnished trebly. Some animals, however, exist without
any whatever. The circulating system, though supplied through the medium
| of the stomach, is nevertheless, by its aid alone, incapable of continuing its
action it requires for this purpose another modification, viz., respiration. It
j *8 ^rora a ^ree communication of the surrounding element with the circulating
1 Sj\S^em undergoes various changes, and appears indeed from

■ this source to receive its vital renewal. All animals possessing a circulating
system have a portion of their vessels destined to communicate the blood with
ertain organs, where it becomes spread out as it were over a large surface, so

10 ,

Mr. Hash's Introductory Lecture

as to render it more capable of a free communication with the surrounding
element. We also find in all animals, whether their local habitation is land or
water, a certain provision of motory organs to attract and repel the surround-
ing element, whether air or water, either into or upon the respiratory organs.

Those animals which possess no circulation, if they are surrounded by air it
becomes diffused through every portion of the body by a kind of elastic tube,
and if water, it penetrates the system by means of vessels, or is absorbed by
the skin. After the blood has been thus nutrified, it appears, as it travels
along, to impart its nourishment to the solids, when it returns to undergo the
same modification. As the fluids are thus undergoing continual changes, so
we find the solids in their turn partake of the same phenomenon, and for each
supply they receive, give off that which is no longer of use to them. Thus we
observe that the blood incessantly renovates the composition of various parts
of the body. We have, besides, the glands, which separate from the blood
those liquids necessary to the animal economy, and others which secrete such
fluids destined for rejection.

The muscular system appears subservient to the nervous, and its action is
regulated according to the increased proportion of excitement received by the
nervous system. Thus the mainspring of life in the animal creation appears
to be the mutual influence of the muscular and nervous apparatus connected
with the arteries and intestines.

From practical experience we have found that irritation existing in one part
may be counteracted by exciting an irritation in another. Now, as the nervous
system, the cause of irritation, is intimately connected through all its parts, we
need not be astonished that sensations or irritations produce debility. If the
stomach is over-loaded, and an uneasy sensation or greater irritation than
natural is produced, many of the other organs become enfeebled. Again, if the
mind from constant meditation is over-excited, it not only loses its power of
recollection, but it is also injurious to the digestive apparatus, and the whole
frame in consequence becomes weakened. Accident or disease may also pro-
duce in every part of the body sensations of greater or less acuteness. Every
animal possesses to a greater or less extent the sensation of feeling, but in
many animals some of the other senses are deficient. We find some without
ears, without -eyes, or without nostrils, and some are destitute of every faculty,
with the exception of sensation.

Every movement of the animal body takes place through the medium of
a sensation, whether voluntary or involuntary. Every extension of parts is
occasioned by muscular contractions. The direction and number of muscles
in each animal are regulated according to the motion the animal may have to
execute, and they vary according to the powers necessary in every species.
When strength is required the muscles have a bony attachment ; the bones
are articulated together so as to allow the muscles to play upon the bones as
so many levers. In the vertebrated animals this strength is usually required,
and therefore bones are necessary for their attachment. In the mollusca, the
hardened parts arc called crusts or scales, and in these not so much power is
requisite. We do not find the muscles directly attached to the hardened parts.

11

to the Science of Comparative Anatomy.

but are connected through the medium of a kind of tendon. I he bones,
which are connected one with the other, are so united as to restrict their
motions to certain directions, and to further facilitate this we have condensed
fibrous cords attached to each of them.

It is from the connexion of these various parts, as well as from the different
forms resulting from them, that animals are capable of exercising the different
motions we find them so naturally perform. The muscular fibres of the heart,
intestines, bladder, &c., as I have before stated, are not under the influence of
the will. In these parts they are either circular, radiated, or straight, but have
no bony attachment ; even in the vertebrated tribe, strength is not here
required. Their motions are, in fact, passive, and it is only either from
paroxysms of rage, or from severe mental disease, that they become at all
subservient to the will ; volition then, as it were, bursting through its boun-
daries, extends its power over these forbidden regions — confusion, irritation,

and disease are the consequences.

With regard to the nervous system, we find it somewhat analogous to the
circulating, more or less developed in every organised being. Some animals
exist without a heart, and others without a brain, and we observe some enjoy-
ing the pleasures of life without either one or the other. All animals, I have
told you, possess a degree of sensation. Man, however, who is empowered
with the greatest nervous mass, is the only animal that is capable of associating
his "general ideas with certain images, so as to call to his mind the circum-
stances they are intended to represent. These images or signs that I am
speaking of, constitute what is termed a language ; their expression by articu-
lation is called speech ; when brought before the eye, they are denominated
ieroglyphics, or writing. By these signs we are enabled to collect an immense
body of materials, and thus strengthen the power of our reason and imagina-
tion ; they afford also a medium of communication, by which means the whole
species are enabled to partake of the experience of each. Thus, knowledge
may be raised in the course of time to an indefinite point of elevation, and
extended to an indefinite distance. Some animals, how'ever, though infinitely
below' mankind in their intellectual faculties, perform many extraordinary
perations ; in short, wre observe in the superior animals something which
imulates reason. We know that by experience they gain knowdedge, and
this knowledge appears regulated independently of the impulses of their ordi-
nary sensations. In their civilised state they know that they are under the
ontroul of man ; they observe his superiority, and are fearful of his rage. They
possess also a faculty very different from human intelligence, viz. instinct, a
acuity which guides them to the preservation of their own species, though
this faculty apparently is altogether foreign to their own desire. The workings
of this faculty can neither be considered the efforts of imitation, nor can we
consider it the principle of reason ; we frequently find the particular actions
produced by this power so extensive, so intricate, and so complicated, and in
wanimals, too, naturally the most stupid. Every species possesses instinct of
■different kinds, and each, with reference to its own species, conducts its labours
■ precisely in the same way : for example, if we take the working bees, we find

12

Mr. Rush's Introductory Lecture

that they have, since the commencement of the world, constructed their
splendid edifices in conformity with the strictest geometrical laws. The
solitary bees and wasps also construct equally beautiful nests, in which they
deposit their eggs ; in a certain time a worm is formed, which in all proba-
bility never beholds its parent, and certainly in that state it would be impos-
sible for it to construct a dwelling equal to that which contained it; but this
worm, the moment it has become metamorphosed into a bee, will immediately
construct an edifice, equally beautiful to that in which it was first deposited as
a worm.

Having now taken a rapid glance at the various and necessary parts of the
animal, I will next proceed and give you a brief sketch of the difference
between it and the vegetable kingdom. I have said that animals are never
destitute of sensation and motion, but we find that vegetables are deprived of
both, and indeed reduced to the mere capacity of vegetation. Some plants,
it is true, appear as if instinctively to withdraw from touch, yet this motion is
too unlike that of animals to afford any proof of volition. One of the most
striking characters which distinguish plants from animals is, that the roots of
the former act as a digestive apparatus, while the digestive apparatus of
animals act as the roots of the former. The organisation of the animal cavity
must of necessity correspond with the nature of the aliment the species subsist
upon ; but we find that plants have always the juices prepared for absorption,
and supplied from the soil and the surrounding element. The functions of
the animal must therefore be of necessity much more complicated than those
of plants. Another leading distinction between the animal and vegetable
kingdom is the circulation ; but I have already told you, that some of the more
simple animals are also deficient in this respect. The muscular and nervous
systems are also a third distinction. The chemical composition of the animal
body also differs from the vegetable. The elements belonging to the vegetable
kingdom, are oxygen, hydrogen, and carbon, while in the animal we have a
fourth, viz. azote. The peculiar composition of plants requires that the
hydrogen and carbon should be retained, and the superfluous oxygen exhaled :
there is also in general a very small portion of azote absorbed, but for the
support of animal life the inverse ratio takes place. The functions of respira-
tion is also another very distinctive difference between animal and vegetable
life. It would almost appear that these kingdoms live one upon the other, for
we find the vegetable composition, of wrhich hydrogen and carbon form the
principal parts, one of the principal sources of nutrition for the animal ; and
again, we find the decomposition of the animal, one of the principal supporters
of vegetable life. There are many interesting and striking facts that we may
trace, when we come to consider the difference between herbivorous and car-
nivorous animals, connected with the vegetable kingdom. These, however, I
will endeavour to point out to you, when we come to the consideration of tins
class of animals.

Having now, gentlemen, laid before you a portion of that general outline
which I propose to finish in the course of this season, I must beg your further
attention while I make a few observations on the great importance which ought

13

to the Science of Comparative Anatomy.

to be attached to the study of comparative anatomy ; for, by its agency, what
is often obscure and too faintly developed in man is rendered plain and con-
spicuous. By its light, as through a powerful optical machine, we are enabled
to view what is microscopic in the human frame on enlarged and more obvious
i dimensions. To describe the amount of pleasure and delight arising in a well
constituted mind from the pursuit of a knowledge so extended, diversified, and
magnificent, so blended with the mighty operations and economy of nature, so
beneficial in its results to mankind, would call for a force of language and
splendour of diction, which requires an advocate gifted with more power ol
eloquence than the humble individual before you can lay claim to ; but to the
lover of scientific research, and the admirer of those harmonious laws, which,

) extending their sway alike over the meanest and the mightiest, point to an
omnipotent and benevolent Creator, I would say, — here is a field where all
you love and admire may be seen and enjoyed, and which is boundless as the
gratification experienced in surveying it. In whatever light we examine this
science, it still presents a most interesting aspect to the observer. To the
mathematician, the symmetry and exact co-adaptation of the different parts ol
widely distinct races, the direction and dimension of the muscles, the moving
powers acting upon solid bony levers, furnish dm pie matter for his speculation ;
he finds the best principle for constructing that triumph of architectural art, the
dome, in the sublime model furnished by the human skull. He submits to
i! admeasurement and calculation the cylindrical bones of various animal bodies,
and finds in all a wonderful economy of substance and adaptation to their
i offices ; nothing superfluous has been admitted, nor anything wasted. Dura-
bility, usefulness, and a saving of the plastic material, distinguish the works of
our Almighty and benevolent mother, Nature ; and it is not declaring too
much, if we aver that, whatever mechanical contrivances the wit of man by
painful research during the long lapse of ages may have invented, their pro-
totype is to be found in one or other of living animated bodies, and requires
but the eye of active investigation into her plans and operations to become
' manifest.

To the geologist, anatomising as it were the depths of the earth, and meeting
in his inquiry the relics of long extinct creations buried within her capacious
bosom, our science affords a light by which he may read their probable dates
of actual existence, their forms while living, and the race to which they be-
! longed ; for, although but a few isolated remains of the perished being are
submitted to the inspection of the comparative anatomist, its whole fabric may
be delineated by him from these scanty materials as accurately as the flow of
a curve can be described from its equation at any given point. The chemist
and natural philosopher will also find in this science scope of indefinite extent
for the prosecution of their peculiar inquiries, tending at the same time to their
gratification, and the triumph arising from fresh discoveries, and to the lasting
information and benefit of mankind. No niggard hand has spread the table at
which they may feast ; their onward course may be prosecuted without fear of
being satiated, they will find new delights present themselves at every step,
and new excitement arising to stimulate the appetite to farther exertion as fast

14

Mr. Hush's Introductory Lecture

as the old ones lade ; in a word, comparative anatomy is the consideration and
analogy of forms simple in themselves, but so infinitely varied and combined
that their range appears to be inexhaustible.

Lastly, gentlemen, after having briefly examined the different component
parts of so extensive a subject, I must take leave to add a few words on its
vastness and exceeding importance to the general interests of scientific know-
ledge, and the benefit of the social community. In its pursuit, whichever way
our steps are directed, new objects are sure to present themselves, and furnish
food for man’s noblest faculty — reason ; from its sources, boundless as the con-
fines of our earth, the poet may gather images to enrich his song, and the philo-
sopher deduce laws and inferences which, when afterwards carried into effect,
may produce consequences as surprising as they are beneficial. There is scarcely
any other science to which the one under consideration may not afford some
degree of light. In the study of human anatomy and physiology, the illustra-
tions it extends to the searcher after truth are indispensable ; they stamp cer-
tainty on points which, without such aid, must have remained conjectural. To
the transformations, also, which have from time to time taken place in our ever
changing globe, comparative anatomy is a faithful guide ; for the geologist,
without the illumination it throws on his abstruse subject, would be a wanderer
in darkness, or a pursuer of shadows whose true forms could not be scanned by
any operation of his intellectual powers. The fossil remains of animals whose
races have been long since extinct, and buried in the strata on which they in
ages gone strode in a degree of might and stupendous magnitude of which
their skeletons alone can now tell, are exhumed by the geologist to throw light
upon his art ; but in this he requires the assistance of the comparative anato-
mist. It is the latter alone can put together the disjecta membra of the broken
up frame-work ; it is he alone can restore the lucidus ordo to the scattered
fabric. But his art is not confined solely to the contemplation of the bony
structure of animals ; he divests this rigid scaffolding of its soft envelope, and
inquires into its form, relations, and offices ; the connecting links, the ligaments,
are scrutinised, and the various powers and functions of the muscles, the moving
apparatus, estimated. Nothing in the animal economy escapes his observation,
and finally, he comjjares, and by the lamp of analogy arrives at certainty, where
before were doubt and imperfect speculation.

The fund of information, both instructive and agreeable, elicited by these
labours of the zootomist, is extensive and highly encouraging to the student m
his pursuit after similar knowlege. Nor is there one of you here present, and
resolved to persevere in a science so rich in materials for pleasure and profitable
attainments, who may not, by his individual exertions, furnish additional facts
and discoveries to those already known. I may here observe, that one of tbe
most surprising and pleasing departments of our science is that which considers
the changes which, during the lapse of ages, life has undergone on the surface
of the globe. The fossil remains of animals which existed antecedent to man
upon the earth, are being continually discovered, both in the old and new
worlds, and furnish proofs, strong as any documentary evidence, concerning the
changes which have through successive centuries taken place in the numerous

to the Science of Comparative Anatomy.

15

races inhabiting our globe ; and facts of the same kind are continually increas-
ing ; and this also is equally true of the vegetation which embellished the earth
at that time, with which of course the animals were in close connexion. Now,
new races of animals and vegetables have made their appearance, and super-
seded those whose ancient existence is only revealed to us by means of their
fossil remains. Thus, in the course of ages which preceded the appearance of
man upon earth, its surface has successively changed its aspect, its verdure,
and its inhabitants ; the seas have nourished other beings, and the air has been
peopled with other birds. I trust that although the field of comparative
anatomy has of late been trodden with much energy and perseverance by some
of our continental neighbours, of whose names I shall have frequent occasion
to make honourable mention in the course of these lectures, that there are yet
innumerable paths leading to useful discovery, in reservation for the exercise of
our national talent, and that, although our countrymen have come late to the
arena of emulative competition in this science, their onward course in its culti-
vation will, at no distant period, not only equal, but eclipse the fame of those
who have gone before them. Gentlemen, the pursuit of this science is, perhaps,
more captivating, after the first difficulties in its study are surmounted, than
that of any other. Many of its subjects are easily obtained, and at an incon-
siderable expense ; others may be observed in the different collections and
museums now fast increasing in this metropolis. Of course the possession of
the more rare specimens must, as in every other case, be the result of individual
enterprize. But the magnitude and extent of this arena of scientific explora-
tion, ought not to terrify or deter the young and aspiring traveller, who would
venture within its bounds. It is true that even if gifted with the highest talent
I he may never reach its utmost limits, for, as I have already said, they appear to
i be infinitely distant ; yet enough may be learned by moderate exertion and
assiduity, by the exertion of that powerful instrument in smoothing all difficul-
- ties— perseverance — to pave the way to a desirable and masterly knowledge of
its secrets. Let no one, therefore, be disheartened at surveying the extent of
this science and its collateral relations, for assuredly a desire to attain it, aided
f by application not closer than is usually bestowed upon the study of inferior
arts, will accomplish the end in view. I say with perseverance, for the mental
1 power, and that readiness of conception which, as it were, at once grasps, and
• intuitively, and rapidly reasons upon whatever subject is laid before it, appro-
j priating it without almost an effort, is not alike vouchsafed to all ; and w'here
' it is wanting, it is consolatory and encouraging to know that there exists
■ another impulse in the human mind, capable of producing results as great as
ever the most splendid natural abilities gave birth to — that property, gentlemen,
is perseverance.

By it the most stupendous results have been effected — by it the slow' in
i apprehension, but laborious in investigation, may, as with a master-key, open
the door to every science. But while impressing on your minds the beauties
of the science which now engages our attention, and inculcating the advantages
which its pursuit will confer, I must not forget that it is my province to do so
with the modesty and humility which becomes a teacher commencing his

16 Mr. Rush's Introductory Lecture , fyc.

arduous career. That such feelings are mine, I beg to assure all now before
me, and, further, to add, that it is my fervent desire, in the execution of the
task I have undertaken, to prove myself worthy of your confidence, and to dis-
charge my duties conscientiously, yet zealously. In doing so I feel convinced
that both my own and the interests of such as may be pleased to rely on me,
and become my pupils, will be best consulted and secured.

It remains now for me, gentlemen, to state briefly the plan which I propose
to follow in the fifteen succeeding lectures I shall have the honour to deliver
during the season, in this theatre. It is my intention then, to invert, in rny
general outlines, the routine ordinarily adopted in teaching the minutiae of the
science ; that is, instead of beginning with the lowest order of animal life, and
ending with the highest and most complex, to describe the latter first, and so
proceed downwards, until we reach that dimly defined and almost impercep-
tible boundary which separates animal from vegetable life. In pursuing this
course, I venture to assert that its parallel may be found in another science as
widely useful and extensive as our own — I allude to the calculation of numbers.

In these operations, in the one instance, we begin from the unit, and descend
in the scale to the smallest infinitesimal, as in decimals ; while in the other, a$ .<
in whole numbers, we commence at the bottom of the standard, and rising,
proceed to its utmost limits. Whichever scale we follow it may be effective m ji
itself, and by reversing their relative positions, perhaps a better understanding ;
of both may be attained. Thus far, then, I mean to innovate on the us™
routine of teaching our science. In my succeeding introductory lectures, I shall
proceed from man, the head of the visible creation, downwards to the verge ol
mere organic life ; but in the more difficult effort of pourtraying the minute
parts of this science, which shall be the business of the next session an oppo- •
site line will be drawn, and commencing with the inferior forms of creation* ►
your attention shall be gradually directed to its supreme limit. Finally, gentle-
men, I have to thank you for your attention this evening, and to entreat, it any
thing has been neglected or omitted in this my opening lecture, the
may meet with that indulgence and favour which erring human nature is too
often in need of, and which I am willing to believe you will kindly concede. B

BRADBURY AND EVANS, PRINTERS, WHITEFRIARS.