I UBRAflf
HUMAN PHYSIOLOGY.
Printed by A. SPOTTISWOODF, New-Street-Square.
HUMAN
PHYSIOLOGY,
BY
JOHN ELLIOTSON, M.D. CANTAB. F.R.S.
PRESIDENT OF THE ROYAL MEDICAL AND CHIRURGICAL
AND OF THE PHRENOLOGICAL SOCIETIES ;
PROFESSOR OF THE PRINCIPLES AND PRACTICE OF MEDICINE AND
OF CLINICAL MEDICINE, AND DEAN OF THE FACULTY, IN THE UNIVERSITY J
SENIOR PHYSICIAN OF THE NORTH LONDON HOSPITAL;
FELLOW OF THE ROYAL COLLEGE OF PHYSICIANS;
FORMERLY PHYSICIAN TO ST. THOMAs's HOSPITAL, AND
PRESIDENT OF THE ROYAL MEDICAL SOCIETY OF EDINBURGH,
ETC. ETC. ETC.
WITH WHICH IS INCORPORATED, MUCH OF THE ELEMENTARY PART OF THE
INSTITUTIONES PHYSIOLOGIC^
OF
J. F. BLUMENBACH, M.D. F.R.S.
PROFESSOR IN THE UNIVERSITY OF GOTTINGEN.
ILLUSTRATED WITH NUMEROUS WOOD-CUTS.
(ZEUitioiu
UNIVERSITY OF LONDON-
LONDON: LONGMAN, REES, ORME, BROWN, GREEN, & LONGMAN,
PATERNOSTER-ROW. 1835.
tavtf
TO
THE STUDENTS
OF THE
UNIVERSITY OF LONDON,
THIS WORK
IS
AFFECTIONATELY INSCRIBED.
JV1347773
..-•
PREFACE.
IN 1815, I translated the third edition of Professor Blu- menbach's " Institutions Physiologic^," anonymously, with the addition of twenty pages of notes ; the whole amounting to two hundred and sixty pages.
In 1817, I published a second edition, with my name, and the addition of a hundred and fifty pages of notes ; the whole amounting to four hundred and twenty-six pages.
In 1820, I published a third edition, with two hundred pages of notes, in smaller type than the text; so that, although the whole amounted to four hundred and sixty-five pages, the matter of my notes very nearly equalled that of the text.
In 1824, I published a fourth edition, from a new edition which had appeared of the original work in 1821. The notes, still in smaller type, filled three hundred and fifty pages, and the whole amounted to five hundred and eighty-one ; so that the matter of my notes greatly exceeded that of the text.
Finding that, in the present edition (which, through my engagements, has been delayed long after the preceding was out of print), my own matter would very much exceed that
Vlll PREFACE.
of Blumenbach, and that much of the original would require emendation on account of recent discoveries or might be better omitted, and that the disjointed nature of the work would be a source of greater inconvenience to the reader than ever, I resolved to remodel the whole, omitting many parts of the original, and blending my notes with as much of it as I could retain : and as the portions of the original retained are of so much smaller amount than my own labours, and of a very elementary character, and the proportions of Blumenbach's share and my own thus completely reversed, I feel satisfied that, in now giving my own name to the work, I shall be justified in the eyes of even the celebrated and venerable Blumenbach, who, though eighty-three years of age, still delivers his lectures at eight o'clock every morning. The passages with inverted commas and no farther intimation are from Blumenbach. I have illustrated many pages with wood- cuts, from Dr. Jules Cloquet's collection, for the sake of the general reader ; since works of this description are now read as much out of the profession as by medical men.
The correction of any errors, and the communication of any facts, either publicly or privately, will always be esteemed by me a valuable favour.
37. Conduit Street, Feb. 14. 1835.
HUMAN PHYSIOLOGY.
I. GENERAL PHYSIOLOGY.
CHAPTER I.
GENERAL VIEW OF THE DEJECTS OF NATURE, AND OF MAN AS DISTINGUISHED FROM THE REST.
NUMEROUS authors have remarked that a gradation exists among all the objects of the universe, from the Almighty Creator, through archangels and angels, men, brutes, vegetables, and inanimate matter, down to nothing.
" Vast chain of being which from God began,
Natures ethereal, human, angel, man, *;-i, 'si jilj
Beast, bird, fish, insect, what no eye can see, No glass can reach, from infinite to thee, From thee to nothing." a
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
3 Pope, Essay on Man, Epistle 1. B
2 GRADATION OF OBJECTS.
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." b
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 magnitude, nor can he boast of more perfection than the gnat or the thistle in their kinds*
Substances 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, and various powers of affecting animated systems.
INANIMATE SUBSTANCES may be gaseous, liquid, or solid. If solid, the inanimate body has no properties which are not analogous to these, or even dependent upon them. It is for the most part
b Dr. Johnson, Review of a Free Enquiry into the Nature and Origin of Evil.
INANIMATE SUBSTANCES, VEGETABLES, AND ANIMALS. 3
homogeneous in its composition, and disposed to be flat and angular, increases by external accretion, has an indeterminate volume, and contains within itself no causes of decay. The rest of the bodies in nature are animated, and are vegetables and animals.
VEGETABLES, in addition to the properties of inanimate matter, possess those of LIFE, viz. sensibility (without consciousness or perception) — I would say excitability, for sensibility without the power of sensation is nonsense, — and contractility; or I would rather express both by the term excitability.6 Their structure is beautifully organised, their volume is determinate, and their sur- faces disposed to be curved ; they grow by interstitial deposition, changing substances to their own nature, and are destined in their very nature for a limited existence, — a period of increase and decay. They contain fluids, some of which they receive, others they produce, and others they discharge.
ANIMALS, in addition to the properties and characteristics of vegetables, enjoy MIND, the indispensable attributes of which are the powers of consciousness and perception, and of volition : the two former, — which are in truth but one, termed consciousness when it takes cognisance of internal impressions, and perception when of external, — without the latter, would be, like vegetable or organic sensibility without contractility, were this possible, useless; and the latter could not exist without the^formerd, any more than vegetable or organic contraction could occur without excitability: nor can the existence of mind be conceived without the faculties of consciousness, perception, and volition, any more than the existence of matter without extension and impenetra- bility. 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
:..,} US : ••*?••>•.- .:.;1, ;.• OJW:)! M ;* CMlJ WU.' i cr-i>!ui •>'}• . v:;! C'i' .eviJI-'f i ' !.;Oti'*.->j '-" .•
c By their possession of the former, stimuli act upon them, and by the latter, they upon stimuli : by the sensibility and contractility of the vessels, substances are taken in by the roots, circulated through the system, and converted into the various parts of the vegetable. Yet this does not imply perception, consciousness, or will. The excitability of the absorbents and secretories of our own system car- ries on absorption and secretion without our consciousness or volition.
d " Sense" says Hamlet to his mother, " sure you have, Else could you not have motion" Act iii. Sc. 4.
B 2
4 BRUTES.
which is not thus gifted certainly deserves not the name of animal.6
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 and perception, and volition, with the appetite for food, or are even nourished by imbibition, and multiply by shoots, fixed like vegetables to the spot which they inhabit. The five senses, sexual appetite, instincts, memory, judgmentf, and loco-
* I cannot conceive an animal without consciousness, perception, and volition ; nor can I conceive these in an animal without a brain, any more than the secre- tion of bile without a liver, or something analogous. I contend not for the name, but for the thing. Zoologists indeed affirm that many internal worms and all the class of zoophytes have no nervous system. But comparative anatomy is yet imperfect, the examination of minute parts is extremely difficult, and new organs are daily discovered. Blumenbach, after remarking that, except those animals •which inhabit corals and the proper zoophytes, most genera of the other orders of the Linnaean class of vermes are found to possess a distinct nervous system, adds: " although former anatomists have expressly declared in several instances that no such parts existed." (Comparative Anatomy, ch. cxvi. F.) Besides, some beings have been denominated animals without any very satisfactory reason.
Where the nervous system of an animal cannot be readily detected, its presence inay be inferred from motions evidently voluntary, such as retraction upon the approach of footsteps, — proving the existence of an organ of hearing, a brain, and nerves : motion in a part directly stimulated, as the contraction of an hydatid upon being punctured, is no proof of an animal nature, for this is common to vegetables, for instance, the leaves of the diontea muscipula, which contract forc- ibly on a slight irritation. It may likewise be inferred from the presence of a stomach, because, where there is a stomach, the food is taken in, not by absorbing vessels constantly plunged in it, but by a more or less complicated and generally solitary opening regulated by volition. John Hunter contended that the stomach was the grand characteristic of the animal kingdom.
f I see daily instances of something deserving some such name as judgment or reason in brutes. To the incredulous I offer the following anecdote in the words of Dr. Darwin. " A wasp on a gravel walk had caught a fly nearly as large as itself. Kneeling on the ground, I observed him separate the tail and the head from the body part to which the wings were attached. He then took the body part in his paws and rose about two feet from the ground with it; but a gentle breeze wafting the wings of the fly turned him round in the air and he settled again with his prey upon the gravel. I then distinctly observed him cut off with his mouth first one of the wings and then the other, after which he flew away with it unmolested with the wind." Zoonomia: Instinct. — The works of the two Hubers, Sur les Abeilles and Sur les Mceun des Fourmis indigenes, furnish
MAN. 5
motive power, with the necessary organs, are variously super- added, and endless varieties of organisation constructed, so that air and water, the surface and the crust of the earth, are all re- plenished with animals completely calculated for their respective habitations. *
Many 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 that brutes have not, and his body being, like the bodies of all animals, constituted in harmony
an abundance of most interesting instances of reason in those insects. See also Mr. Smellie's paper in the Transact, of Royal Society of Edinburgh, vol. i. p. 39. sqq.
e An error has been committed not only in representing the gradation regular, but in supposing every species of animal to constitute a distinct step in the grad- ation. «« The whole chasm in nature," says Addison (Spectator, No. 519.), " from a plant to a man, is filled up with divers kinds of creatures, rising one above another, by such a gentle and easy ascent, that the little transitions and deviations from one s'pecies to another are almost insensible." " All quite down from us," says Locke (Essay on the Human Understanding, b. iii. c. 6.), " the descent is by easy steps, and a continued series of things, that in each remove differ very little one from the other. There are fishes that have wings, and are not strangers to the airy region ; and there are some birds, that are inhabitants of the water ; whose blood is cold as fishes, and their flesh so like in taste that the scrupulous are allowed them on fish days. There are animals so near of kin both to birds and beasts, that they are in the middle between both : amphibious animals link the terrestrial and aquatic together, seals live at land and at sea, and porpoises have the warm blood and entrails of a hog ; not to mention what is confidently reported of mermaids or sea men." " In respect of our intellectual and moral principles," remarks Mr. Dugald Stewart (Outlines of Moral Philoso- phy, par. 109.), " our nature does not admit of comparison with that of any other inhabitant of this globe : the difference between our constitution and theirs being a difference, not in degree, but in kind. Perhaps this is the single instance in which that regular gradation, which we, every where else, observe in the universe, fails entirely."
Now the various kinds of animals do certainly run into each other ; — there are no great peculiarities of construction in single organs between which and the ordinary structure of the same organs in other animals an intermediate structure connecting the two are not continually brought to light by naturalists. No two are so different but that discoveries are continually made of a third intermediate. But connection is not gradation. Many kinds, and the intermediate ones by which they are united, are all on a level in point of excellence and combination of properties, so that a single step in the gradation may comprehend a great number of kinds : — the whole vegetable kingdom forms but one step.
B 3
6 MAN.
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 !"h
The orang utans 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 propaga- tion of alarm ; to seem now and then to laugh and weep 5, to walk a little occasionally erect, to defend themselves with sticks and stones, to copulate face to face, to carry their young either in their arms or on their backs, and to be very lascivious in regard to our species ; — the orang utans at first sight afford, if any of the genus can afford, a little probability to the opinion of a close con- nection between apes and the human race. Uncivilised 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.k These we shall review under two divisions, the
h Hamlet, Act ii. Sc. 2.
1 Le Cat (Trait^ de V Existence du Fluide des Nerfs, p. 35.) asserts that he had seen the jocko or chimpanzee (simia troglodytes) both laugh and cry. The reader will remember the lines in Milton's Paradise Lost (B. ix.), —
" Smiles from reason flow, To brute denied. "
The orang utans exhibited a few years ago at Exeter 'Change, — the one a satyrus and the other a chimpanzee, — are said by their keepers to have sometimes laughed when much pleased, but never to have wept. Steller states the fact of Mreeping in regard to the phoca ursina; Pallas, in regard to the camel ; and Hum- boldt, in regard to a small American monkey. Mr. Lawrence, Lectures, p. 236. * In La Fontaine's charming fable of Le Singe et U Dauphin, the former
MENTAL CHARACTERISTICS OF MAN. 7
first embracing the mental, and the second the corporeal, charac- teristics of mankind.
In judging of the mental faculties of mankind1, 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 utan, but, if instruction is afforded to both, the former will gradually develope the powers of our nature in their noble superiority, while the latter will still remain an orang utan. The excellence of man's mind demonstrates itself chiefly
during a shipwreck, near Athens, resolves to profit by his resemblance to man, for whom the dolphin was anciently said to have a great regard. (See Pliny, Hist. Nat. ix. 8, 9.) In the hurry,
Un dauphin le prit pour un homme, Et sur son dos le fit asseoir Si gravement, qu'on cut cru voir Le chanteur que tant on renomme.
Just before landing him, the dolphin asked whether he often saw the Piraeus, to which he unfortunately replied,
Tous les jours : il est mon ami : C'est une vieille connaissance.
One glance was sufficient to discover the difference between a man and a monkey.
Le dauphin rit, tourne la tete ;
Et, le magot considere,
II s'apper9oit qu'il n'a tire"
Du fond des eaux rien qu'une bete ;
II 1'y replonge, et va trouver
Quelque homme a fin de le sauver.
" The difference between the volume of the brain of the orang utan and man is as 5 to 1 : their convolutions differ considerably in number and structure ; the anterior lobes especially are narrowed into a cone, flattened above, hollowed out below, &c. and the difference is much more striking in other apes." Gall, 1. c. t. vi. p. 298.
1 In the external senses of at least smelling, hearing, and seeing, man is sur- passed by brutes. Whether they have any sense not possessed by us I cannot pretend to say.
'
8 MENTAL CHARACTERISTICS OF MAN.
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 estab- lishments. 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, me- chanical contrivance, the sense for music and language, 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 decided reflecting faculties of comparing and reasoning into causes.
The corporeal characteristics of mankind are not less striking and noble.m 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 seem'd lords of all." n
The erect posture is natural and peculiar to man.o All nations walk erect, and, among those individuals who have been disco-
m Consult Blumenbach, De Generis Humani Varietate Nativa. Sect. i. De Hominis a cseteris Animalibus differentia.
n Paradise Lost, book iv. 288.
* There is little necessity in the present day to attempt the refutation of the ridiculous opinion that man is destined to walk on all-fours. But I do so for the purpose of displaying many peculiarities of our structure.
It is almost incredible that a thinking man could have entertained it for a moment, any more than the idea of our naturally having tails. Yet this is the fact ; and, in exquisite ridicule of such philosophers, Butler makes Hudibras, after proving to his mistress by his beard that he is no gelding, fruitlessly urge his erect posture in proof that he is not a horse.
" Next it appears I am no horse, That I can argue and discourse, Have but two legs, and ne'er a tail. — Quoth she, That nothing will avail ; For some philosophers of late here Write, men have four legs by nature, And that 'tis custom makes them go, Erroneously upon but two.
CORPOREAL CHARACTERISTICS OF MAN. 9
vered in a wild and solitary state, there is no well authenticated instance of one whose progression was on all-fours. If we at- tempt this mode of progression, we move either on the knee* 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 \ 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, shows 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 in every direction towards objects; the fore-arm extends itself out- wards, 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
As 'twas in Germany made good B' a boy that lost himself in a wood, And growing to a man was wont With wolves upon all- four to hunt."
Hudibras, part ii. canto i.
10 CORPOREAL CHARACTERISTICS OF MAN.
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 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. P 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 shallow 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, conversely,
P As the head is connected with the trunk farther back in brutes than in us, the small length of lever between the occipital foramen and the back of the head, and the length of the head below the foramen, require all this power ; but even in us much more upholding power than we have at the back of the neck would be required for all-four progression, as the head would no longer rest upon the spine.
CORPOREAL CHARACTERISTICS OF MAN. 11
were their situation so changed, the provision for the sitting pos- ture would be comparatively useless.
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 ignorance have asserted that monkeys are destined for the upright posture. The monkey tribe, it is true, maintain the erect posture less awkwardly than other brutes with four extremities, but they cannot 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, ani- mals. 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 (slmia paniscus) have not this organ. The whole length of the orang utan, 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 particular, and as rats and mice too surpass the dog, the horse, and the elephant, in the comparative bulk of their brains, this opinion also gave way, in its turn, to that of Sommerring, — 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 (grant- ing that they originate from it) is not an accurate measure of the faculties, because the seal has in proportion to its nerves a larger
12 CORPOREAL CHARACTERISTICS OF MAN.
brain than the house-dog, and the porpoise than the orang utan.q
- 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 the 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, however, 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 proportion 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 per- pendicular, 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 utan 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 mouth; it shows merely the projection of the forehead, while the cranium and brain may vary greatly in the size of other parts ; three- fourths of quadrupeds, whose crania differ extremely in other re- spects, have the same facial angle ; great amplitude of the frontal sinuses, as in the owl and hog, without any increase of brain, may increase 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 margin
i See Gall, 1. c, t. ii. p. 281. sqq.
CORPOREAL CHARACTERISTICS OF MAN. IS
elevated ; in most quadrupeds it is situated at the extremity of the cranium obliquely, with its posterior parts turned upwards, and is in some completely vertical. On this difference of situation, Daubenton founded his occipital angle. r 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. Blumen- bach remarks that its variations are included between 80° and 90° in most quadrupeds which differ very essentially in other points.
The want of the ossa intermaxillaria has been thought peculiar to mankind. Quadrupeds, and nearly all the ape tribe, have two bones between the superior maxillary, containing the denies in- cisores when these are present, and termed ossa intermaxillaria, incisoria, or labialia. But these do not exist universally in them. 8 Man only has a prominent chin : his lower jaw is the shortest, compared with the cranium, and its condyles differ in form, direc- tion, and articulation, from those of any brute : 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 back- 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 utan 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 ; the curve of the vagina corresponding with the curve of the sacrum formerly mentioned, preventing woman from being, as brute females are, retromingent ; the peculiar structure
r Memoires de f Academie des Sciences de Paris. 1764.
s In a chimpanzee that died at Exeter Change a few years ago, the statement of Tyson and Daubenton was verified, — that this black ape has no intermaxillary bone. The red-haired variety (Simia Satyrus) has it, and is said to be destitute of nails on the hind thumbs and of ligamentum teres at the head of the os femoris, both which structures this chimpanzee possessed. The Satyrus is therefore not so near the human subject as the Troglodytes. In a simia satyrus, however, lately dissected at the Zoological Gardens, the hind thumbs possessed nails. Proceed- ings, $c. Nov. 23. 1830.
14 DEFINITION OF PHYSIOLOGY.
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 mem- brane; are likewise structural peculiarities of the human race. The situation of the heart lying not upon the sternum, as in quad- rupeds, 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 l ; he is the slowest in 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. For " a species comprehends all the individuals which descend from each other, as from a com- mon parent, and those which resemble them as much as they do each other" ;" and no brute bears such a resemblance to man.
The knowledge of all the objects and laws of nature might be supposed to be signified by the term physiology, derived as it is from <fv<Ti^ nature, and Xo-yo?, a discourse. But the term is restricted to vegetables and animals, and indeed solely to their functions. The knowledge of their structure is designated ANATOMY ; the knowledge of their functions PHYSIOLOGY.
Both anatomy and physiology are divided into vegetable and animal; and the latter again into brute, or comparative, and human. The subject of the present work is HUMAN PHYSIOLOGY: but the functions of brutes and vegetables will frequently be mentioned.
* Blumenbach accounts for this, and I think justly, by the two-fold operation, of our intellect (I.e. § 18. p. 54.), and of the more accommodating nature of our frame (1. c. § 17.).
u Cuvier, Discows Preliminaire aux Recherches sur les Ossemens Fossiles des Quadrupedes.
15
CHAP. II.
GENERAL VIEW OF THE CONSTITUENTS OF THE HUMAN BODY.
THE ultimate PRINCIPLES of animal bodies, forming the distinct compounds, whether gases, fluids, or solids, are: — Hydrogen, Carbon, Oxygen, Azote,
Chlorin, iodin, fluorin? Sulphur, Phosphorus, Potassium, Sodium, Calcium,
Magnesium, silicium? Manganese ? Iron,
Copper ?a
The proximate PRINCIPLES, or distinct chemical compounds of animal bodies, are : — Albumen, Fibrin,
Colouring matter of blood, Curd,
Fatty matter, (olein! I stearin,
Gelatine, obtained from various tex- tures by boiling,
Matters found in the bile, — cho- lesterin, erythrogin, asparagin, picromel ?
Mucus, and probably some other products of glands at present but little understood,
Subject to great variety in different animals, &c.
8 The ultimate principles of vegetables may be considered the same as those of animals.
16 ULTIMATE AND PROXIMATE ANIMAL PRINCIPLES.
Urea,
Cystic oxide, xanthic oxide,
Uric acid,
Erythric acid?
Purpuric acid,
Oxalic acid,
Acetic acid,
Lactic acid,
Butyric acid,
Formic acid,
Benzoic acid,
Sulpbo-cyanic acid,
Sugar of milk,
Sugar of diabetic urine,5
b Vegetable proximate principles are very numerous : considered the chief: —
Not subject to variety ; uniform in all in- stances.
the following may be
- '
Sugar, Starch, Lignin,
Gum, mucus, jelly,
Extractive, colouring matters, bitter prin_ v. All subject to endless variety as t.jp]es | occurring in different plants.
Gluten
Oils, fixed and volatile, Resins,
The following are constant in their character, or are peculiar to certain vegetables.
Various acids — Oxalic, citric, tartaric, malic, moroxylic, gallic, laccic, kinic,
boletic, prussic, meconic, benzoic, &c. Various alkaline bodies — Quinina, cinchonina, morphina. strychnina, brucina,
delphina, picrotoxina, atropia, veratrina, hyoscyamina, &c. Indigo, Tan, Suber, Caoutchouc, Wax, Asparagine, ulmine, inuline, fungine, polychroite, haematine, nicotine, pol-
lenine, emetine, sarcocol, olivile, medulline, lupuline, cathartine,
piperine, daphnine, salicine, populine, digitaline, santonine, cafeine,
hordeine, elatine, &c, &c.
ULTIMATE AND PROXIMATE SOLIDS. 17
The ultimate SOLIDS, which these principles are said to compose, are, the cellular fibre, the muscular fibre, and the nervous fibre. c
The proximate SOLIDS, said to be composed of these primary, or rather ultimate, or elementary solids or tissues, and forming the different organs, have been variously specified.*1
Dr. Carmichael Smyth, in an admirable paper upon inflammation, considered that disease according to the structures which it affects, — the skin, cellular membrane, serous membranes, mucous mem- branes, and muscular fibres.6 Dr. Pinel, some years afterwards, adopted this arrangement f; and Bichat at length suggested that all diseases might be considered in this manner, and he distributed the proximate solids into twenty-one kinds : —
1. Cellular, 12. Fibro-cartilaginous,
C2. Nervous, of animal life, 13. Muscular, of animal life,
3. Nervous, of organic life, 14. Muscular, of organic life,
4. Arterial, 15. Mucous,
5. Venous, 16. Serous,
6. Exhalant, 17. Synovial,
7. Absorbent, with its glands, 18. Glandular,
8. Osseous, 19. Derrnoid,
9. Medullary, 20. Epidermoid,
10. Cartilaginous, 21. Pilous.8
11. Fibrous (tendino-fibrous),
c See Appendix, by Dr. Copeland, to his translation of Richerand's Nbuveaux Eldmens de Physiologic, p. 553. sqq. Many writers have asserted the globular composition of various parts of the animal and vegetable frame. Lately, the cel- lular, muscular, and nervous structures were described as consisting of globules, and some novel views presented, by Dr. M. Edwards. (Archives Generates de Medecine, t. 3. Paris, 1823.) But the whole results have been denied by Dr. Hodgkin and Mr. Lister, who repeated the examination with a much superior microscope. Phttos. Magazine, August, 1827.
Another author professes to have made still more minute discoveries than Dr. Edwards. Dutrochet, Recherches, Anatomiques et Physiologiques, sur la Structure Interne des Animaux et Vegetaux.
d " The ancients divided the body into similar or homogenous parts, — those consisting of particles similar to one another, as the bones, cartilages, muscles, tendons, &c.; and dissimilar, — those composed of the similar, as the head, trunk, limbs," &c.
e Medical Communications, by a Society for the Promotion of Medical Knowledge, vol. ii. 1790. Read to the Society, Jan. 1788.
f Nosographie Phttosophiquc, 1797. e Anatomic Gentrale, t. i. p. Uxx.
C
18 ULTIMATE AND PROXIMATE FLUIDS.
This arrangement, Dr. Rudolph! remarks, is physiological rather than anatomical, and he distributes them into eight classes only: —
Cellular, Tendinous,
Horny, Vascular,
Cartilaginous, Muscular, and
Osseous, Nervous.h
The ultimate and proximate FLUIDS of the body, generated by its functions, whether for its own use, or for elimination from it, may perhaps be viewed as,
Aqueous, Oleaginous,
Mucous, Bilious,
Albuminous, Urinous,
Fibrinous, Seminal.
The first fluid is that derived from external matter, — the chyle; then that into which this is formed, and which is dis- tributed through the system, — the blood ; then the various fluids produced from this.
To show the preponderance of the fluid over the solid matter of the body, Blumenbach states that he possesses the entire, but perfectly dry, mummy of a Guanche, or aboriginal inhabitant of Teneriffe, presented to him by Sir Joseph Bankes, which, with all its muscles and viscera, weighs but seven pounds and a half. *
h Grundriss der Physiologic, 68.
* Instit. Physiol. sect. 1. edit. 4. Getting*, 1821.
19
CHAP. III.
GENERAL VIEW OF THE ORGANS, FUNCTIONS, AND POWERS OF THE HUMAN BODY.
THE proximate solids are made up into various organs ; and the operation of an organ is termed its function.
While a part is performing its functions, and even while it only remains in a condition fit for the performance of its functions, changes of its constituent particles go on ; indeed, many func- tions are in a great measure but chemical changes. The separ- ation of one portion of matter must occasion the addition of another to be necessary. Hence organs are framed for receiving matter from without, and for changing it variously, so as to fit it to become a portion of the fluids of the body; for distributing it through the body, and rendering it a part of the body ; and for the separation and elimination of those particles which in the course of the chemical changes must quit the system. We thus observe organs of reception, assimilation, circulation, nutrition, secretion, and excretion. As individuals last but a limited time, the species is preserved by the generation of new beings from individuals. Organs of generation are therefore framed ; but this function is merely circulation, secretion, excretion, and nutrition.
We perceive external objects and circumstances; are conscious of much within ourselves ; we think, desire, and exert volition. The organs of these functions are termed the nervous system. It exists in mass, and is also ramified throughout the frame. Im- pressions upon the extremities of its ramifications, as well as upon these in their course, are conveyed along them to the mass, where they are perceived; and the mandates of the will are conveyed from the mass along the ramifications to fleshy organs of motion, termed muscles; and the influence of emotion is also conveyed from the mass along the ramifications to every part.
c 2
20 GENERAL VIEW OF THE FUNCTIONS.
The ancients arranged all these functions in four classes : — The vital, or those constantly necessary to life, comprising respir- ation and the action of the heart : the natural, or those by which the body is nourished: the animal, or those which principally distinguish animals from vegetables, viz. sense, consciousness, desires, thought, volition : and the genital.
The functions are now generally arranged in two classes : the animal, constituting one peculiar to animals ; and the vital and natural, 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, except the animal passion, are 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 a and Xavier Bichat b~; 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, is conscious, desires, reflects, 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 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 correspon- dent, 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, spinal marrow, nose, tongue, &c.
a 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.
b Recherches Physiologiques surla Vie et la Mort. 1805.
GENERAL VIEW OF THE FUNCTIONS. 21
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 continually differ in size, figure, and situation: the two lungs are very dis- similar. °
Hence Bichat infers, that in the animal functions a harmony of action in each organ, or in each half of the organ, is indispensable to perfection, when both organs or sides act together ; and that if such harmony do not occur, it is better for one organ or one half to act alone. This certainly appears true of the eye, and ear, and even of the brain. 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 duplicity 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 func- tions 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
c As the nerves of one perpendicular half of the body are connected with one half of the brain or spinal marrow, it is not surprising that we often see a loss of motion or of sense, or the reverse, viz. spasms or convulsions, or even an ex- cess of sensibility, in one perpendicular half of the body. But we have examples of ague affecting only one perpendicular half of the body (Ephemer. Nat. Curios. and Memoires de Montpellier, 1 827) : of persons who sweated on one perpendicu- lar half only, (Ephemer. Nat. Curios. Dr. Abercrombie on Diseases of the Brain and Nerves (the line on the face was distinctly marked), p. 284. Dr. Andral, Clinique, vol. i. p. 477.) : and of a child that became pale and emaciated in one perpendicular half, while the other remained plump and healthy. (Dr. Falconer, Memoirs of London Med. Soc. vol. ix. ) Still, as we have paralysis and convulsions also in a horizontal half, so instances are on record of ague affecting a horizontal half (Journal de Medecine, t. xxiv. p. 60. January, 1766); and of one horizontal half sweating (Andral, #>.) : and as we have also examples of paralysis and convulsions affecting a limb only, so ague is said sometimes to have seized but a single limb. (Dr. Macculloch, on Marsh Fever and Malaria.)
c 3
22 GENERAL VIEW OF THE FUNCTIONS.
see that the actions of the heart, lungs, &c., have 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, — the more frequently an object is applied to our organs of sense, the less intense is the sensation produced by it ; and the more frequently we perform an act of volition, the more readily is it performed. Yet I think the force of habit equally great over the organic functions. The operation of food and of all de- scriptions of ingesta is most remarkably modified by habit; through it poisons become comparatively innocuous, 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. d
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 functions, 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 voluntary muscles, the organs of sense, and even in the brain, circulation, 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-
d Bordeu, Buffbn, Cabanis, and the anatomist Reil, placed the passions in the thoracic and abdominal viscera, &c. ; the two first in the diaphragm particularly. Gall has shown the absurdity of these authors in his Fonct. du Cerveau, t. ii. p. 93. sqq. We might as well consider the cheeks the seat of the feeling of shame, because in shame we blush. Hippocrates opposed such absurdities in his day. " The heart and praecordia," says he, " feel acutely,* but have not the least intelligence : the brain is the cause of all these things." De Morbo Sacro.
GENERAL VIEW OF THE FUNCTIONS. 23
tility, and organic sensibility and contractility, besides the common extensibility of matter, which he terms extensibilite de tissu, and common contractility upon the removal of distension, — contrac- tilite par defaut tf extension, which, indeed, is greater during life than afterwards.6 Animal sensibility is accompanied by a perception
e The following is Bichat's table of the properties of the living body : —
Classes. Genera. Species. Varieties.
1
1 C Animal Sensibility -I 2
1 J [ Organic Vital 1 1
2 r Animal 1
Contractility J _ C Sensible Such as the motion of the
2 f Extensibility l_ Insensible Such as the motion of the Structural •{ 2 capillaries.
\^ L Contractility
Although these are the general properties of the living frame, and sensibility, or more properly excitability, is at the bottom of all the other vital or organic properties except the active power of contraction, yet each part has also some peculiarity, altogether inexplicable, — not in the least, I think, to be accounted for on Bichat's supposition of each part possessing a certain degree of organic sen- sibility in relation to its fluids. What causes the vessels of muscle to produce muscle ; of bone, bone ; of membrane, membrane ; what causes the secreting vessels of the liver to form bile, and of the testes semen, we know not. The causes of these circumstances are called by Blumenbach, after Bordeu, vitce proprice ; but it must be carefully remembered, that this expression simply denotes an unknown cause of a fact, and affords no explanation.
Feeling (I use the word for want of another to embrace consciousness and perception) is in the same manner at the bottom of all the mental properties except the active power of willing, but it alone will not explain them. All matter is probably the same ; but its modifications likewise are so various, that at present we are compelled to speak of distinct kinds of matter.
The operation of agents on the system is analogous. As far as they all affect the living solid, they may be all called stimuli ; but they differ in something more than degree of stimulus. Each affects particular parts more than others ; each affects in a peculiar way ; some directly depress life, and many occasion opposite results in different parts ; some produce specific diseases, in which the composi- tion of the fluids may be altered ; and here occasionally the specific disease pro- duced is contagious.
When organic sensibility is heightened in one part, it sinks in another, and vice versa ; unless the change of it should be such as to extend generally, and even then it is still frequently found in the opposite state in some particular part . v. c. we notice coldness and paleness of the feet, and heat and fulness of the head,
c 4
24 GENERAL VIEW OF THE FUNCTIONS.
in the mind, as in seeing, hearing, tasting, smelling, feeling: animal contractility is excited by the volition of the mind con- veyed to the voluntary muscles by means of the nerves. Organic sensibility is attended by no perception, and is followed by con-
together ; blisters relieve internal inflammation, and irritate the more difficultly in proportion to the violence of the internal disease. The same phaenomena are observable in animal sensibility and in the mind at large : —
" Tut, man ! one fire puts out another's burning,
One pain is lessen'd by another's anguish ; Turn giddy, and be holp by backward turning ;
One desperate grief cures with another's languish ; Take thou some new infection to thy eye, And the rank poison of the old will die."
SHAKSPEARE. Romeo and Juliet, act i. sc. ii.
The effect of vicissitudes of temperature, and a large number of other patho- logical phaenomena, are principally explicable on the derangement of the balance of excitability, and for the most part, consequently, of circulation.
Notwithstanding it is a general law that the effects of an agent diminish the more frequently it is applied, and vice versa, as shown on the one hand, in the large quantities of spirituous liquors which persons at length bear, and on the other by the violent inflammation excited by the application of warmth to parts exposed to intense cold ; yet, if a stimulus is applied so energetically as to leave the sensibility heightened, especially if to the point of inflammation, its subsequent power is greatly increased. Immense potations of spirituous liquors may gradually be borne, but if the increase is too great, the sensibility of the stomach may become such that a single glass will prove violently irritating.
The general law, to which the effects of agents, in proportion to their previous application, is referable, appears to be this ; — that an agent acts according to the difference between its strength and the strength of the former application. Thus, if the right hand be immersed in water of 30°, and the left in water of 50°, and both are removed to water of 70°, the effect of the water at 70° upon the right hand will be greater than upon the left, on account of the difference between 30° and 70° being greater than between 50° and 70°; and this explains the glow of the cold bath, as, during immersion, there is less stimulus, and, on emerg- ing, the temperature of the atmosphere, and the re-admitted blood into the super- ficial vessels, though stimuli absolutely of the same strength as before immersion, are, comparatively, more powerful than what the system experienced during immersion.
The specific action of one agent frequently prevents or destroys that of another : v. c. small-pox and measles very rarely occur together ; the former disease is frequently prevented for ever by the cow-pock ; bark cures the effect of marsh
GENERAL VIEW OF THE FUNCTIONS. 25
traction totally independent of the will : — the heart is said to feel (physiology has no proper term for the idea, but excitability would answer the purpose) the stimulus of the blood, and, without our influence, forthwith contracts ; the lacteals to feel the stimulus of the chyle without our knowledge, and they then propel it
miasmata. It in some cases destroys its own power in future, as is exemplified in those diseases which occur usually but once during life.
These observations on rare and frequent agency may relate to agency in general or by particular agents. A very high or low excitement may influence the effects of all subsequent stimuli ; but the rare or frequent application of a particular agent in less intensity may influence its own effects only, as is exemplified in the acquired capability of smoking or taking snuff, while other vapours or powders affect no less than usual.
While moderate excitement is necessary to maintain action and excitability, and excitement by one stimulus, within due limits, augments the effects of an- other, violent excitement wears out the power, and, very violent, may suddenly destroy life altogether : according to the verses,
Nutritur ventis, ventis extinguitur ignis, Lenis alit flammas, grandior aura necat.
Dr. John Brown, seizing the undeniable general facts respecting the effect of rare or frequent application upon the power of stimuli, and naming all agents stimuli, founded a system of pathology and practice at once absurd and destruc- tive. (Elementa Medicince.} Exhaustion, from excess of stimulus, he termed direct debility ; torpor, from deficiency of stimulus, indirect debility ; and how- ever inflammatory a disease, if it arose from a stimulus, it was to be treated by violent stimuli, to prevent the excitability from falling too low.
In the first place, he abused the word stimulus, by confounding it with the word agent, forgetting what has been just advanced respecting the peculiar pro- perties of every agent, — that some depress, and thus, though agents, are not stimuli ; and some affect different parts differently ; and some have a specific power upon certain parts and certain diseases, and against other agents.
In the second place, he forgot what has been just said respecting the necessity of a certain degree of excitement to maintain excitability ; the effect of one sti- mulus, within due limits, of increasing the effect of others ; and the fact of a stimulus producing so much excitement, that morbid sensibility occurs, far less stimulus than was at first applied causing ten times the effect, and this being reducible only by lessening all stimuli, — the temperature, the quantity of blood, &c., and stimulating distant parts. He forgot, also, the effect of sympathy and specific action.
His error was in keeping in view some general laws, which all know and acknowledge, to the exclusion of others of at least equal importance.
26 GENERAL VIEW OF THE FUNCTIONS.
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 heart, yet every organ of the organic functions may have its organic sensibility heightened into animal sensibility, as inflamma- tion, 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 commu- nications.
The animal functions have not only a shorter existence than the organic, from their necessity of alternate repose g, but they flourish for a shorter duration, — they do not commence till birth, they decline, and, in the natural course of events, terminate, earlier, v. c. the organs of sense and the mental faculties fail be- fore the action of the heart and capillaries. But the decay of the animal functions must, in truth, be only the consequence of the decay of the organic, because there are fundamentally in every part organic functions, — circulation, nutrition, &c.; and the per- fect performance of these in the organs of the animal functions is indispensable to the perfect performance of the animal functions. Hence the impairment of these organic functions, even to a small extent, must derange or diminish the animal functions, and the decline of the latter is really owing to the decline of the former, although these still remain vigorous enough to appear unimpaired.
f There is no proof of feeling. There can be no feeling. We see them act in consequence of the stimulus, and say they feel. The expression is only admissible figuratively, but as all figurative terms in physiology are continually accepted literally, and establish the most absurd notions, especially among the vulgar, it had much better be explained by a mere expression of the fact, by the word excitement.
8 It is said that the heart has the same repose as the brain, the auricles and ventricles acting in succession, and a pause occurring before their action is renewed. The function, however, of the heart as a whole organ, constantly goes on ; while that of the brain, at least if it is only an organ of the mind, entirely intemits in sound sleep.
LIFE. 27
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 pro- perties, — 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 maintains a correspondence with the whole machine, influenced by and in- fluencing the most distant parts.
The ORGANIC FUNCTIONS depend on LIFE, in the proper accept- ation 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 pre- serve 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 separation11; to produce peculiar matters for its own purposes ; 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) independently of mere impulse, attraction, or repulsion : or if not organised (as the fluid which becomes the embryo, the blood,) the power of matter produced by an organised body endowed with the properties above mentioned, to resist the ordinary chemical influences, and even directly form (as the embryotic fluid) an organised system so endowed, or directly become, (as the fibrin, when it is secreted from the blood or blood is effused, becoming vascular, and its new vessels inosculat-
h So striking is this, that Stahl and his followers referred their notion of life to this antiseptic property, and while he said, " Life is formally nothing more than the preservation of the body in mixture, corruptible, indeed, but without the occurrence of corruption," Junker said, " What we call life is the opposite of putridity."
Chemical affinities are not destroyed by life, but only so brought to play that decomposition is not their result. Without the operation of chemical affinities the composition of the body could not exist, nor many of its functions, as respir- ation, secretion, &c., take place. The physical properties of matter are equally indispensable. Cohesion, gravity, hardness, softness, and fluidity are essential, in different parts ; elasticity performs an important part in many functions, as in respiration and the rise of the epiglottis ; the laws of light and sound are indis- pensable to the functions of the eye and ear.
28 LIFE.
ing with those of adjoining parts,) the organised substance of an already formed system so endowed.
That fluids as well as solids are susceptible of life, 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 conceive the circumstance as a West Indian to conceive that water may by cold become solid. It is impossible to deny that the male or female genital fluid, or both, either alone or when united, are alive, because from their union, or from one when influenced by the other, a living being is produced which partakes of the vital qualities of each parent. Accordingly Blumenbach, in his Commentatio de vi vitali sanguini deneganda, grants both male and female genital fluids to be alive1, notwithstanding that he fancies his victory over the defenders of the blood's life so complete, that, like that of the unfortunate Carthaginian Dido, he says, " in ventos vita recessit." It is as easy to conceive the blood to be alive as the genital fluids. k
Many facts adduced as arguments of its life are certainly expli-
1 In universum sane post omnia quae super hoc argumento sive meditando sive experiundo hactenus elicere licuit, nulli humorum nostri corporis genuina vis vitalis tribuenda videtur, si unice a genitali utriusque sexus latice discesseris, utpote cui jam ante quam uterino cavo exceptus et intime mixtus in foetus forma- tionem abit, vitales inhaerere vires formativas, praeter alia paterni vultus in nepotes propagata similitude, aliaque id genus phaenomena baud infitianda demonstrare videntur." Comment. Soc. Reg. Societ. Gotting. vol. ix. p. 12.
k The doctrine of the life of the blood was maintained by Critias and his sect among the ancients (Aristotle, De anima, cap. 2.), Harvey (Exercit. L. De Generationis ordine, &c.), Glisson (De ventriculo et inteslinis), and Albinus. (Blu- menbach's Commentat. 1. c. ) I am surprised that Moses should have been adduced by Harvey as authority for this opinion. When he says (Leviticus, ch. xvii. 11. 14. ), " For the life of the flesh is in the blood," — " For it is the life of all flesh," — he can only mean, that, when it is withdrawn, life ceases, — that it is necessary to the life of animals. He also says, (v. 14.) " the blood of it is FOR the life thereof." The construction which would make Moses assert that the blood is alive, involves the absurd assertion that the blood only is alive. Indeed, before the time of Moses, the expression was used to Noah. In Genesis (ix. 4.) we read, " Flesh with the life thereof, which is the blood thereof, shall you not eat." The whole of the matter appears to be, that the Jews, like other neighbouring nations, were in the habit of tearing limbs and cutting flesh from living animals, and eating these portions raw. Saul's army after a battle did this. (\ Samuel, xiv. 32, 33.) To prevent this horrid cruelty, they were forbidden to eat flesh before the animal had been drained of its blood, and thus deprived of life ; and what is, in our own version of the Bible, rendered, « flesh with the life thereof, which is the blood
LIFE. 2.9
cable without such a supposition. Its freedom from putrefaction while circulating may be owing to the constant renovation of its particles ; for the thinness of hybernating animals at the end of their torpid season shows it has received accessions even in tnem, and this from the absorption of fat. Its inability to coagulate after death from arsenic, opium, and some other narcotics, and from lightning and electricity (though Sir C. Scudamore found it to coagulate as usual in the latter case), from hard running, anger, or a blow on the stomach, all three of which deprive the muscles of their usual stiffness, may depend upon chemical changes. The admixture of opium with the blood has been said to prevent its coagulation, and this by destroying its life. But Sir C. Scudamore found that the admixture of prussic acid and belladonna, both strong poisons, has no such effect, and that many mere salts, as common salt, weaken or prevent its coagulation, and these are not likely to kill it, but to act chemically. Its accelerated coagulation by means of heat, when frozen by cold, and some other circum- stances, and the reverse, were believed to depend upon an affection of its vitality, but are, perhaps, referable to some chemical effect. Its earlier putridity when drawn from young than from old per- sons may arise from its inferior qualities. Parts die if deprived of a supply of blood ; yet, though necessary as a material and agent to maintain the life of parts, it is not, therefore, necessarily itself alive. But the circumstance of its freezing more readily, like eggs, frogs, snails, &c., when once previously frozen (which change may be supposed to have exhausted its powers !), is, if really the case, an argument in favour of its life, as these are certainly endowed with life. The organisation of extravasated blood m, and the inosculation of new vessels with those of surround- ing parts, shows n that the solidified lymph is now endowed with
thereof," is said to be rendered by the best interpreters, " flesh or members torn from living animals having the blood in them." See Bruce, Travels to discover the Source of the Nile, vol. iii. p. 297.
I Corrie, on the Vitality of the Blood, p. 45.
m J. Hunter, Treatise on the Blood, $c. p. i. ch. 1.
II Dr. John Thomson believes, that, when blood has been effused between divided surfaces, its coagulum is absorbed, and secreted lymph only coagulates and be- comes vascular. Lectures on Inflammation, p. 214. Yet at page 216. he does not deny the occurrence.
30 LIFE.
life ; and one may more easily believe it to have been alive in the mass of blood, than that it should have acquired vitality after its effusion. Indeed Sir Everard Home declares that a coagulum of blood becomes vascular out of the body, and may be injected0; but if the vessels are formed by the mere extrication of carbonic acid gas, as he contends, their mere formation is no proof of life.
John Hunter believes that the chyle is alive, and some that vivification commences in the stomach ; and Albinus grants life even to the excrement. But the excretions must be regarded as dead matter, useless and foreign to the system, and they all run with the greatest rapidity 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 filth and disease.
The essential nature of life is an impenetrable mystery, and no more a subject for philosophical enquiry than the essential nature of attraction or of heat. To attempt explaining the phenomena 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, whether 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 followers have given, might not be useful even to physical enquirers." p We see matter in a certain state possessed of a certain 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 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 addi-
0 Phil. Trans, vol. cviii. p. 188. sq.
p Elements of the Philosophy of the Human Mind, vol. i. p. 8.
LIFE. SI
tional 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 John Hunter's works for such an hypothesis Q, and Mr. Lawrence has had no better success1", so that I apprehend his meaning has been misunderstood by those who constitute him its patron. 8 Granting for a moment that life depends upon a peculiar, fine fluid, we have still to ac- count for mind, because life is not mind, — a cabbage is as much gifted with life as the wisest man. Yet those whose faith makes life a subtle fluid strangely imagine that the doctrine of a soul is thereby advanced. The life of a brute requires a subtle fluid as much as the life of a man, and of a cabbage as much as the life of a brute.
We have reason to believe that life never originates, but began at the creation, and is communicated to assimilated matter, and propagated from parent to offspring. It is the property of or- ganised systems, producing various effects by various kinds of organisation, but is not quite peculiar to organised matter, because capable of being possessed by matter in a fluid state.1
* Annah of Medicine and Surgery > 1817, p. 373. In the Treatise on the Blood, (p. 89. sq.) John Hunter says, " Life is a property (not a subtle fluid) we do not understand." This property he conceives to reside in a certain matter similar to the materials of the brain ; diffused through the body and even con- tained in the blood. " The brain," he adds, " is a mass of this matter, not diffused through any thing, for the purpose of that thing, but constituting an organ in itself." This materia vitas is, therefore, not subtle, but pretty solid, and no other than medullary matter ; and Vauquelin says he has discovered a fatty matter in the blood, and which M. Chevreuil thinks he proves to be the same as the substance of the brain and nerves. But the subtle-fl uidists would not tolerate gross fatty matter, and J. Hunter calls life a property.
T Lectures on the Physiology, Zoology, and Natural History of Man, p. 84. 8 J. Abernethy, Lectures delivered before the Royal College of Surgeons. 1814.
* As the fluids which form the embryo must be endowed with life, organisation cannot be the cause of life ; but in truth, organisation is the effect of life, although when produced it becomes an instrument of life. The erroneousness of the French doctrine, that " life is the result of organisation," was refuted in the Annah of Medicine and Surgery. (1816, Sept. pp. 346. 386.) The error appears to have arisen in some measure from the want of definition, — the word life being used sometimes properly for the power, sometimes improperly for the result. Even if the result of life, — the functions of a part, should be called its life, life could not be said to be the result of organisation, but of a power to which organis- ation is an instrument. The Greeks had distinct appellations for the cause and the result ; the former they termed tyvxh ; the latter, £(rij.
32 MIND.
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, or by some nervous organ, whatever name we may choose to give it, endowed with life. I speak of terrestrial or animal mind ; with angelic and divine na- ture 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, (Divinez particula aura *, Ex ipso Deo decerptus, Ex universa mente delibatus x,) appears to me absolute nonsense. Brutes are as really endowed with mind, — with a consciousness of personality, with feelings, desires, and will, — as man. * Every child is conscious that it thinks with its head, and common lan- guage designates this part as the seat of mind. z Observation shows that superiority of mind in the animal creation is exactly commensurate with superiority of brain * ; that activity of mind
u Horace.
x Cicero, De Senectute et Queest. Tuscul.
J See Gall, 1. c. t. 1. p. 56. sqq. Aristotle no sooner asserts that a share of divinity is bestowed on man " only of all animals," than he is obliged to retract, and say, " or most of all animals," — fy }i6.\i(rra iravruv. Depart, animal. 1. ii. c. 10.
z A stupid person is honoured with the expressions numb-set*//, thick-foarf, addle-pafed, shallow-pated, badly furnished in the upper story; a clever person with strong-headed, long-headed, having plenty of brains ; a madman is said to be wrong in the head, touched in the noddle, &c. A person whose memory or power of attention is impaired, says he has no head, &c. When a catarrh chiefly affects the head, we complain of stupidity, because " we have such a cold in the head," &c. A man is always said to have an idea in his head.
a " The same progression which exists in the gradual perfection of animal organisation, as far as regards vegetable life only, is observed in the gradual perfection of the nervous system, and of animal life which depends upon it. Comparative anatomy has followed the gradual perfection of animals, from the most simple absorbent vessels to the most complicated apparatus of mastication, deglutition, and digestion, — to the most perfect circulation. With every fresh viscus, every fresh apparatus for sensation, is discovered a fresh function, and this function is more complicated in proportion as the organisation of the viscus or apparatus of sensation is more perfect. The stomach, kidneys, lungs, heart, eyes, ears, are the more complicated as their functions become so.
" The same gradation may be demonstrated in the structure of the brains of the different species. I have demonstrated in the preceding chapter, that the exist- ence of each moral quality and intellectual faculty, depends solely upon the
MIND. 35
and of brain are coequal ; and that, as long as the brain is en- dowed with life, and remains uninjured, it, like all other organs, can perform its functions, and mind continues; but, as in all
presence of certain determinate cerebral parts, and not upon the whole mass of brain. It follows, that the number of the faculties is in direct proportion to the integrant parts of the brain. In insects, fish, and amphibia, the nervous mass contained in the cerebral reservoir, is still divided into several distinct masses. The greater part of these are not integrant parts of the brain, properly so called ; they are ganglia, from which arise the nerves of smell, hearing, sight, &c. The two hemispheres, properly so called, are placed behind the 'two ganglia of the olfactory nerves, and are the more complicated as the industrial instincts are more numerous; the cerebellum in these animals generally forms a hollow pouch, sometimes placed horizontally, sometimes folded together.
" In birds, the two hemispheres are already more considerable, although distinct convolutions cannot be discerned. The cerebellum still consists merely of its middle or fundamental part; but already appears composed of many rings placed side by side.
" In the small mammalia, the shrew-mouse, mouse, rat, squirrel, weasel, &c. convolutions are not yet discoverable. But as they are already distinctly found in other larger rodentia, the beaver, kangaroo, &c., we may suppose that they equally exist in them.
" In the larger mammalia, the cat, polecat, marten, fox, dog, ape, the convolutions are more distinct and numerous, but their form varies according to the species.
" In the dolphin, elephant, and man, they are more numerous and deep than in the beaver, kangaroo, cat, &c., and their form and direction vary completely ac- cording to the species.
" In all the mammalia, the cerebellum possesses, besides the middle or funda- mental part, two lateral parts, which are more or less complicated, according to the species ; and as the soi-disant pons varolii, or the soi-disant cerebral ganglia, i. e. the transverse layers of nervous bands, are only the commissure or junction of the lateral parts of the cerebellum, they are found in all the mammalia, and in none of the ovipara.
" The number of the integral parts, or of the convolutions of the brain, varies equally in the different species of mammalia; in some, the anterior lobes of the hemispheres are larger or more elevated ; in others, again, the inferior parts of the anterior lobes are nearly wanting. The middle lobes, and the other convolutions, present similar varieties.
" In this way, the integrant parts of the brain augment in number and develope- ment, as we pass from a less perfec to a more perfect animal, till we arrive at the brain of man, who, in the anterior-superior, and in the superior region of the frontal bone, possesses several parts of which other animals are deprived, and by- means of which he is endowed with the most eminent qualities and faculties, with reason, and the feeling of religion and the existence of God." Gall,
34 MIND.
other organs, when its life ceases, its power to perform its function ceases, and the mind ceases : when disease or mechanical injury affects it, the mind is affected, — inflammation of the stomach causes vomiting, of the brain delirium, a blow upon the loins suppres- sion or alteration of the urine, a blow upon the head stuns; if ori- ginally constituted defective, the mind is defective c ; if fully de-
1. c. t. ii. p. 364. sqq. " Some pretend to discover a striking resemblance between the brain of an orang-utan and that of man. But, in the first place, the difference of their volume is as five to one ; their convolutions differ considerably in number and structure ; the anterior lobes, especially, are contracted into a cone, flattened above, hollow below, &c. ; and the difference is still more remarkable in other simiae." t. vi. p. 298.
c See Gall, 1. c. t. i. p. 196. sqq., and t. ii. p. 322. sqq. " Willis has described the brain of a young man imbecile from birth; its volume is scarcely ith part of that of an ordinary human brain. M. Bonn, professor at Amsterdam, has two little crania of idiots, and the brain of an imbecile who attained his twenty-fifth year, and was so stupid, that he was shown for money as an African savage," &c. " I have observed heads equally small in many living idiots from birth. All these crania and heads are 13 or 14 inches in circum- ference, and 11 or 12 inches from the root of the nose to the foramen occi- pitale." — "With from 14 to 17 inches in circumference; and about 10 or 12 from the root of the nose to the foramen occipitale, we have more or less stupidity, a more or less complete incapacity to fix the attention upon one object; uncertain
and transitory feelings and passions; confusion of ideas," &c " Heads of 18 or
18^ inches in circumference are still small, although they permit a regular exer- cise of the faculties ; they possess but a sad mediocrity of talent, a spirit of servile imitation, &c. ; an extreme deficiency of seizing the relation between cause and effect ; a want of self-government, and often few desires. Still some qualities or faculties may be considerable, because particular organs may be greatly developed, forming a striking contrast with the mediocrity of the rest. But as we approach larger brains, we see intellectual faculties of greater magnitude, till we arrive at heads 21 or 22 inches in circumference, — the dimensions at which men obtain the height of intelligence." Gall means French inches, which are about ^g longer than the English.
" The dimensions of the brain," says Dr. Magendie, " are proportioned to those of the head. In this respect there is a great difference in individuals. The volume of the brain is generally in direct proportion to the capacity of the mind."—" It is rarely found that a man distinguished by his mental faculties has not a large head." — Precis de Physiologic, t. i. p. 184.
Dr. Marshall, an anatomical lecturer in London from two-and-forty to six- and-twenty years ago, taught that the brain was the organ of mind, its original defective conformation a source of idiocy, its disease the cause of insanity ; and gave many dissections of maniacs, and an excellent sketch of the varieties of the disease. Morbid Anatomy of the Brain, $c. collected from the papers of the late Andrew Marshall, M,D., by S. Sawrey, London, 1815.
MIND. 35
veloped, and properly acted on, the mind is vigorous : accordingly, as it varies with age, in quality and bulk, is the mind also varied, — the mind of the child is weak and very excitable, of the adult vigorous and firm, and of the old man weak and dull, exactly like the body d ; and the character of the mind of an individual agrees
d If of children it is said,
" Inter se quas pro levibus noxiis iras gerunt?
Quapropter? quia enim qui eos gubernat animus, infirmum gerunt."
Terence, Hecyra.
The old man, — " Res omnes timide gelideque ministrat,
Dilator, spe longus, iners — " Horace, Ars Poetica.
Or, in the plainer language of Shakspeare, " Old men have grey beards, their faces are wrinkled, their eyes purging thick amber and plum-tree gum, and they have a plentiful lack of wit, together with most weak hams."
Hamlet, act 2. sc. 2.
Mr. Dugald Stewart allows that " In the case of old men, it is generally found that a decline of the faculties keeps pace with the decay of bodily health and vigour. The few exceptions that occur to the universality of this fact, only prove that there are some diseases fatal to life, which do not injure those parts of the body with which the intellectual operations are more immediately connected." — Outlines of Moral Philosophy, p. 233.
" Praeterea gigni pariter cum corpore, et una Crescere sentimus, pariterque senescere, mentem." Lucretius, lib. i.
" In new-born children, it is difficult to discern, without maceration in spirits of wine, any traces of fibres in the great collections of grey, reddish substances, or the great cerebral ganglia, which supply, reinforce, and perfect, or which, ac- cording to the opinion of others, give activity to, the hemispheres. The nervous fibres are more visible in the middle and posterior lobes than in the anterior. The fibrous structure of the white substance of the cerebellum also becomes apparent gradually, and in proportion to its developement. All the nervous fibres are at this period still so involved in the more or less reddish and gelatinous substance, and in blood-vessels, that all the brain looks like a nervous pulp or jelly.
" The only functions of the infant, at this age, are very imperfect, and are those of the five senses, of voluntary motion, hunger, the sensation of being comfortable or uncomfortable, and the want of sleep.
" After some months, the parts of the brain situated near the anterior-superior region of the forehead, grow more rapidly than the other parts. The forehead, from being flat, becomes prominent, and the child begins to fix its attention upon external objects, to compare, and form abstract ideas, — to generalise.
<* The whole brain is developed in succession, until, at the age of from twenty to forty, it has attained its full growth relatively to each individual. The cerebel- lum, likewise, which is smaller than the cerebrum in proportion as the subject is
D 2
36 MIND.
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 ex- ceeds the male in excitability as much as her body6; the qualities of the mind are also hereditary f, which they could not be, unless they were, like our other qualities, corporeal conditions ; and the mind is often disordered upon the disappearance of a bodily com- plaint, just as other organs, besides the brain, are affected under similar circumstances, — 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-
younger, is developed and perfectly formed towards the age of from eighteen to twenty. The youth, the young man, and the young girl, take an interest in each other ; and the talents and inclinations are exercised and perfected till they obtain maturity. From thirty or forty years of age, the cerebrum and cerebellum remain nearly stationary till the fiftieth or seventieth year, according to individual constitution. The same is the case with the moral and intellectual powers. Certain parts of the brain, however, especially those in the anterior- inferior region of the forehead, have at this time already begun to diminish ; the memory is less faithful, and the imagination less ardent, and hint to us the approach of old age, and the decline of our faculties.
" At length all the cerebral mass gradually loses its nervous turgescence ; it diminishes, wastes, shrinks (' the convolutions lie farther from each other ; ' t. i. p. 192.) ; the consistence of its two substances undergoes alteration. The moral and intellectual powers sink in proportion ; the inclinations, the talents disappear, the affairs of the world assume a gloomy aspect, the past only is considered good ; and, at the age of decrepitude, there remains only imbecility, the weakness of a second childhood." Gall, 1. c. t. ii. p. 156. sqq. ; also t. iii. p. 28. sqq. Dr. Magendie allows that " the brain is almost liquid in the foetus, firmer in infancy, and still more so in manhood " (Precis de Physiologic) ; that above the age of seventy, the weight of the brain is on the average yyth less than in the prime of life ; and that the convolutions are then often distant half an inch from each other, and their surface very distant from the cranium, as Cotugno had observed. Journ. de Physiol. t. vii. p. 5. 87.
e " Mulieres sunt, ferme tit pueri, levi sententia." — Terence, Hecyra.
f " Parentibus liberi similes sunt non vultum modo et corporis formam, sed animi indolem, Bt virtutes, et vitia. — Claudia gens din Romas floruit impigra, ferox, superba : eadem illachrymabilem Tiberium, tristissimum tyrannum pro- duxit : tandem in immanem Caligulam et Claudium, et Agrippinam, ipsumque demum Neronem, post sexcentos annos desitura." — Gregory, Conspectus Medi- cinee Theoretics. So true is the verse
" Et patrum in natos abeunt, cum semine, mores."
MIND. 37
nate with each other, just like affections of other organs; the laws of the mind are precisely those of the functions of all other organs, — a certain degree of excitement strengthens it; too much exhausts it ; physical agents affect it, and some specifi- cally, as is the case with other functions, for example, narcotics. The argument of Bishop Butler, that the soul is immortal and independent of matter, because in fatal diseases the mind often remains vigorous to the last g, is perfectly groundless ; for any function will remain vigorous to the last, if the organ which per- forms 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 upon 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 by those who bring them forward. An exact parallel to each may be found in the affections of every other organ, and each admits of so easy an explanation, that it may be always truly said, '« Ex- ceptio probat regulam. "h
s The Analugy of Religion, natural and revealed) to the Constitution and Course of Nature. By Joseph Buller, LL.D. Lord Bishop of Durham, p. 33.
h I will not insult the understanding of my readers by showing that we have no authentic instance of the real absence of brain in the cranium of a being possessed of a mind. The records of medicine no less teem with wonders than those of theology. The miracles of the Fathers and of the Romish Church may be matched by cases not only of mind without brain, or some similar organ, but of human impregnation without males, or by males without testes, and of human foetuses nourished without communication with the mother.
In most cases where the mind is said to have been vigorous when the state of the body at large, or of the brain alone, rendered the perfect performance of the cerebral functions improbable in the eyes of the relaters, I believe the mental power has been greatly over-rated, — that, because the individual merely talked collectedly, he was imagined sufficient for the exertions of his best health.
The part of the brain affected by disease may have been one whose function is not intellectual, but merely relating to the feelings, or may have related to intellectual faculties whose state was not noticed by the narrators. In truth, the narrators give us no satisfactory account of the feelings and intellectual powers of the patients, nor of the exact portions of the brain affected ; nor could they, being unacquainted with phrenology ; and they also forget that the cerebral organs are all double. (See Gall, 1. c. t. ii. 188. sqq., 246. sqq. ; and a paper by Dr. Andrew
D 3
38 MIND.
I have placed the preceding arguments alone, but to them may be subjoined another equally demonstrative as any, — that the stength of the various intellectual powers and inclinations accords with the size of the various parts of the brain ; that exactly as the various parts of the brain are successively developed is the character developed, and as they shrink with age does the cha- racter again change.
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 his revelation; for the word and the works of the Almighty cannot
Combe, on the effects of injuries of the brain upon the manifestation of the mind, in the Transactions of the Phrenological Society, Edinb. 1824.)
If after insanity no trace of disease is sometimes discoverable in the brain, let us remember that the same is sometimes the case after epilepsy and various un- doubted diseases of the brain, and sometimes with respect to the stomach after chronic dyspepsia. Diseases may be functional only. Nay, when our senses are not nice enough to discover structural affection of the brain in insanity, &c. we have generally strong presumptive evidence of its affection, in the thickening or excessive secretions of its membranes, — points more easily ascertained than equal changes in the delicate texture of the brain.
Those who thus attempt to prove the substantial distinctness of the mind and brain, forget that their facts, or rather arguments, are equally strong against what they all admit, — the necessary connection of the mind and brain in this life ; and are therefore grounded on what, if true, were violations of the course of nature.
There is a passage in Hippocrates, de Morbo Sacro, well worth quoting : — " Men ought to know, that from the brain only proceed pleasure and joy, and laughter and sport, as well as griefs, anxieties, sorrows, and weeping. By it we are wise especially, and understand, and see, and hear, and appreciate what is base and honourable, good and bad, pleasant and unpleasant, distinguishing them partly by habit, partly by their utility. By it we distinguish what is pleasurable, and what disagreeable, according to circumstances ; and, by it, the same things do not please us under all circumstances. By it we are insane and delirious ; expe- rience terrors and fears, partly by night, partly by day; and sleeplessness, and ill- timed errors, and groundless cares; do not recognise those who are with us; lose our habits, and forget our experience. And all this we suffer from the brain if it is not healthy, &c. : wherefore I say, that the brain is the messenger and inter- preter of intelligence and wisdom. But the praecordia have obtained the name of Qpevet among the Greeks, by custom, not from fact and nature ; and I know not what property they have of knowing and understanding, except that in sudden and great joy or sorrow they leap," &c.
MIND. 39
contradict each other. Bacon accordingly, in a very memor- able part of his writings, directs the physical enquirer to be unin- fluenced by religious opinions1, as the more independently truth is pursued the sooner will it be gained, and the sooner will the real meaning of a divine statement of natural things, and the conformity of this to physical fact, be established.
The assertion, however, that the mind is a power of the living brain, is not an assertion that is material ; for a power or property of matter cannot be matter.
Neither is it an assertion that this power cannot be a something immortal, subtle, immaterial, diffused through and connected 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, medullary matter though it be. Seeing that the brain thinks, and feels, and wills, as clearly as that the liver has the power of producing bile, and does produce it, and a salt the power of assuming a certain form, and does crystallise, he leaves others at liberty to fancy an hypothesis of its power being a subtle, immaterial, immortal substance, exactly as they fancy life to be a subtle fluid, or, perhaps, though very extraordinarily, the same subtle fluid (if subtlety is immateriality and immortality) k, elucidating the subject
1 Si quis animum diligentius advertat, non minus periculi naturali philosophise ex istiusmodi fallaci in iniquo foedere, quam ex apertis inimicitiis imminere. Tali enim foedere et societate accepta, in philosophia tantum comprehend!, aucta autem, vel audita, vel in melius mutata, etiam severius et pertinacius excludi. Denique versus incrementa et novas veluti eras et regiones philosophise, omnia ex parte religionis, pravarum suspicionum et impotentis fastidii plena esse. Alios siquidem simplicius subvereri, ne forte altior in naturam inquisitio ultra datum, et concessum sobrietatis terminum penetret, &c. &c. Quare satis constabat in hujusmodi opinionibus multum infirmitatis, quin et invidiae et fermenti non parum subesse," &c. — Cogitata et Visa, vol. ix. p. 167. 8vo edition. In the same para- graph he remarks, with regret, that no writers are more popular than those who pompously set forth the union of divinity and philosophy, i. e. faith and sense, as if it were not illegitimate. t( Haud alias opiniones et disputationes magis secundis ventis ferri reperies, quam eorum, qui, theologiae et philosophise conjugium, veluti legitimum, multa pompa et solemnitate celebrant, et grata rerum varietate animos hominum permulcentes, interim divina et humana inauspicato permiscent."
k The hypothesis of a subtle mobile fluid is downright materialism — the doc- trine of Lucretius.
. " Quoniam est animi natura re"perta MobUis egregie, perquam constare necesse est Corporibus parvis et Icevibus atque rotundis." Lib. iii. 204. D 4
40 MIND.
no more than in the case of life, and equally increasing the number of its difficulties l ; as though we were not created beings,
Bacon complained (1. c.) that the first attempts to explain thunder and tem- pests were accused of impiety by religious persons, who thought that religion demanded these phenomena to be referred to the immediate operation of the Deity. The lovers of subtle fluids and spirits, conversely and as strangely, think religion served by interposing a subtle fluid between common matter and the Deity. Van Helmont was remarkably fortunate, for, after severe meditation, he fell into an intellectual vision, and saw his own soul : " Magna mox quies me invasit, et incidi in somnium intellectuale satisque memorabile." It was very small, and had no organs of generation : " Vidi enim animam meam satis exiguam, specie humana, sexus tamen discrimine liberam." — Ortus Medicince, Coufessio auctoris, p. 13. He gave the soul, however, a close and dirty dwelling, for he placed it, not in the pineal gland, but in the stomach.
1 Locke (Second Reply to the Bishop of Worcester, p. 477. 8vo edition) in disparaging philosophical reasons for the immortality of the soul, says,
" Dr. Cudworth affirms that there was never any of the ancients before Chris- tianity that held the soul's future permanency after death (f. e. from its inherent immortality), who did not likewise assert its pre-existence." If we necessarily shall exist to all eternity, we then must have existed from all eternity ; yet we are not aware of having been alive before our brains. Sterne's fine ridicule of the absurdities introduced by this hypothesis of a soul, and that independent of the brain, into the Romish church, is well known. A great French man-midwife acquaints us that he baptised a little abortion of the magnitude of a skinned mouse ; and on another occasion, when a woman was miscarrying in her fourth month, and the child's posteriors presented, that he sprinkled water upon them and baptized them, in case the little thing should turn out alive. (De la Motte, Traite complet des Accouchemens, p. 243. 246.) Dr. Foder£ in his noted Me- decine Legale, 1813, (vol. ii. p. 62.) gravely suggests that baptism may always be administered by a squirt, after the membranes are pierced, — " Quant au bap- teme, il me semble qu'il sera toujours facile de 1'administrer, apres avoir perc6 les membranes, par le moyen d'un seringue a injection." A good idea of what follows in its train may be collected from Dante's tiresome account of the intro- duction of the soul into the body, beginning, " Sangue perfetto che mai non si beve," &c. — Purgatorio, canto xxv. It is one parent of necromancy, of the belief in ghosts, and of all the popish " trumpery " respecting purgatory and the worship of dead people called saints, of the opinions held by many respecting our oc- cupations between death and doomsday, as if a future state began before; and old writers sicken one with their notions about the period at which the soul enters the body, when it first existed, how it was engaged before it united with the bod)', and how it employs itself after its separation till the day of judgment, &c. " Hierom, Austin, and other fathers of the church, hold that the soul is immortal, created of nothing, and so infused into the child or embryo in his mother's womb six months after the conception ; some say at three days, some six weeks, others otherwise." — Burton's Anatomy of Melancholy > p. 1. s. 1. m. 2 subs. 9. Where
MIND. 41
or not altogether ignorant what matter is, or of what it is capable and incapable ; as though matter exhibited nothing but extension, impenetrability, attraction, and inertness ; and as though an Almighty could not, if it seemed good to him, have endowed it, as he most evidently has, with the superaddition of life, and even of feeling and will.™
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. n Our
the depot of souls is ; how they learn when a youth has impregnated an ovarian vesicle, and how they fly to and get into it ; how it happens that the qualities of the soul correspond with the brain, and are as hereditary as those of the body ; whether this depends upon souls varying, and, if so, how a soul finds a body just corresponding to itself; or upon the soul being obliged to conform to the cha- racter of the brain, and thus suffering by the brain's defects, we are not satisfac- torily informed.
m « All the difficulties that are raised against the thinking of matter, from our ignorance or narrow conceptions, stand not at all in the way of the power of GOD, if he pleases to ordain it so." The faculties of brutes prove, " either that God can and doth give to some parcels of matter a power of perception and thinking, or that all animals have immaterial and consequently immortal souls as well as men ; and to say that fleas and mites, &c. have immortal souls as well as men, will possibly be looked on as going a great way to serve an hypothesis."— -Locke, Second Reply to the Bishop of Worcester, p. 466. 8vo edit.
" Si quelqu'un de'montreroit jamais que 1'ame est mate'rielle," says the pious and benevolent Bonnet, " loin de s'en alarmer, il faudroit admirer la puissance qui auroit donn6 a la matiere la capacite" de penser."
" In the ordinary derivation of plants and animals," says Paley, " from one another, a particle, in many cases minuter than all assignable, all conceivable dimensions ; an aura, an effluvium, an infinitesimal ; determines the organis- ation of a future body : does no less than fix, whether that which is about to be produced shall be a vegetable, a merely sentient, or a RATIONAL being; an oak, a frog, or a philosopher ; makes all these differences; gives to the future body its qualities, and nature, and species. And this particle, from which springs, and by which is determined, a whole future nature, itself proceeds from, and owes its con- stitution to, a prior body," &c. — Natural Theology, conclusion, p. 591.
n Miscellaneous Tracts, $c. by Richard Watson, D. D. F. R. S. Lord Bishop of LlandafF. Sermon iii. p.- 399. sq.
42 MIND.
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 improveableness of our characters, —
« ... this pleasing hope, this fond desire,
This longing after immortality,
this secret dread and inward horror
Of falling into nought," P
have been thought to completely harmonise with a life hereafter, but certainly fall so short of proof as to have left the wisest of antiquity, — Solomon, Socrates, Cicero, &c. — in uncertainty q, when they saw how death reduces us to our pristine elements. The hope of immortality inspired by such reflections, 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 reason for our not totally perishing as our senses would lead us to suppose. But, because we refuse to listen to a mere hypothesis respecting spirit, we are not necessa- rily 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. r — The scripture so pronounces,
e Heathens have, very consistently with this reason for immortality, given it to the fancied souls of brutes : Ulysses is made by Homer to behold the shade of Orion —
&f)pas 6{Ji.u fl\evvra, /car' acrQodeX'bi' Xet/tava
Tovs avrbs KarfirfQvw Iv oloir6\ouriv optffffi. Odyss. A. 571.
Dr. Thomas Brown believed, " that the metaphysical ARGUMENT which proves the immortality of man, extends with equal force to the other orders of earthly existence." Memoir of Thomas Brown, M.D., by the Rev. David Welsh. 1828, p. xxii.
And " Bonnet promised brutes immortality."
P Addison, Cato. See a full enumeration in Mr. Dugald Stewart's Outlines, &C. p. 235. sq.
9 Bishop Watson, 1. c. Sermon vi. p. 504. sq.
* " Nor can we be obliged, where we have the clear and evident sentence of reason, to quit it for the contrary opinion, under a pretence that it is a matter of faith, which can have no authority against the plain dictates of reason. But
MIND. 43
— not that we are naturally immortal, but that " in Adam (by nature) all die8, — have our being utterly extinguished4, 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 Christ, but, consequently, by a miracle, not by our nature")— we shall all again be made alive. St. Paul declares the resurrec-
there are many things wherein we have very imperfect notions, or none at all ; and other things, of whose past, present, or future existence, by the actual use of our faculties, we can have no knowledge : these, as being beyond the discovery of our natural faculties, and above reason, are, when revealed, the proper matter of faith. Thus, that part of the angels rebelled against God, and thereby lost their first happy state, and that the dead shall rise and live again : these and the like, being beyond the discovery of reason, are purely matters of faith, with which reason has nothing directly to do. " — Locke, Essay on Human Under- standing, iv. ch. 18.
Reason's province is only to examine the proofs of the authenticity of a reve- lation, and faith should thus be founded on reason. But how few of the human race ever think, or are even capable, of carefully examining them ! And of those who do examine them, how few do not commence the examination with their minds unconsciously half made up ! And yet the greater number look down with a self-complacent and uncharitable feeling upon even good men, whose opinions differ in any respect from their own ; forgetting that good conduct is the only test of goodness, — that grapes cannot come from thorns, nor figs from thistles.
The question of the authenticity of Scripture is altogether foreign to this work.
s Bishop Watson, Apology for the Bible, Letter x. near the end.
* Idem, Miscellan. Tracts, 1. c. — Dr. Law, Bishop of Carlisle, in his Theory of Religion, &c., which went through seven editions, asserts that the sentence of death passed upon Adam and Eve meant nothing less than a total destruction of existence ; and that the idea of its implying a continuation of consciousness and real existence in some other place than earth, is not sanctioned by Scripture, but is the philosophy of after-ages. — p. 345. He adds, that Bishop Tillotson, though a patron of this notion, confesses it is not found in the Bible : and, after a critical and elaborate examination of the words used in Scripture to denote soul and spirit, and their various applications, he sums up the enquiry thus : — " But neither do these words, nor any other, so far as I can find, ever stand for a purely immaterial principle in man, or a substance, whatever some imagine they mean by that word, wholly separable from, and independent of, the body."
Bishop Sherlock employs strong expressions : — " Scholars may reason on the nature of the soul, and the condition of it when separated from the body: but the common hopes of nature receive no support from such enquiries. We die and moul- der to dust ; and in that state, what we are, or where we are, nature cannot say." Discourse ii. p. 85. and vol. iv. p. 79.
M Bishop Watson, Apology, 1. c.
44 MIND.
tion to be " a mystery .•" it must, in truth, be a miracle; and there- fore the enquiry, " how can these things be," altogether fruitless. The miracle of Christ's resurrection, to which the Scriptures refer us as the foundation of the hope of a future state, would not have been necessary to convince us of a necessary truth, discoverable by sense and reason. That the promises of the New Testament 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 powerful 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 grounded on the truth of Christianity. "*
x Anecdotes of the Life of Richard Watson, D.D. F.R.S. late Lord Bishop of Llandaff. — Vol. i. p. 107. See also a very decisive passage, beginning — " As a Deist, I have little expectation ; as a Christian I have no doubt, of a future state," in his Apology for the Bible, Letter x. near the end.
Bishop Jeremy Taylor, in his Doctrine of Original Sin, p. 24., assures us that the words — " Since by man came death, by man came also the resurrection from the dead," and, " as in Adam all die, even so in Christ shall all be made alive," directly affirm that a resurrection, or being made alive again, is granted, assured, and executed by and in Christ alone ; and evidently suppose that the dead are not made alive till the resurrection, and that, had not a resurrection been provided, we should never, after death, have been made alive.
Locke argues, " that all the great ends of religion and morality are secured barely by the immortality of the soul, without a necessary supposition that it is immaterial." — First Reply, p. 34.
Mr. Dugald Stewart concedes that " the proper use of the doctrine of the immateriality of the soul is not to demonstrate that the soul is physically and necessarily immortal." 1. c. p. 227.
Dr. Rush, of America, remarks upon this subject, " that the writers in favour of the immortality of the soul have done that truth great injury by connecting it necessarily with its immateriality. The immortality of the soul depends upon the will of the Deity, and not upon the supposed properties of spirit. Matter is in its own nature as immortal as spirit. It is resolvable by heat and moisture into a variety of forms ; but it requires the same almighty hand to annihilate it, that it did to create it. I know of no arguments to prove the immortality of the soul but such as we derive from the Christian revelation." — Medical Inquiries and Observations, vol. ii. p. 15.
" I rather think," says Dr. Priestley, " that the whole of man is of some uni- form composition, and that the property of perception, as well as the other powers that are termed mental, is the result (whether necessary or not) of such an organised structure as the brain. Consequently, that the whole man becomes extinct at death, and that we have no hope of surviving the grave, but what is derived from the scheme of revelation." — First Introductory Essay to his Edition of Hartley, p. xxiii. sq.
MIND. 45
While those are wrong who think there can be any thing like an argument against a future life in another order of things, if de- clared by a revelation, it is strange that others should think it necessary to attempt rendering the pronunciations of scripture more probable, and that by an hypothesis which is at best but the remains of unenlightened times y, and should require any as-
y The more uninformed the age, the greater the disposition to explain every thing. The savage personifies the winds and the heavenly bodies ; the ancients fancied all matter endowed with a spirit — spiritus intus alit. Philo and Origen maintain that the stars are so many souls, incorruptible and immortal. In the older writings of the moderns, even in those of the father of experiment and observation — Lord Bacon, the properties of matter are referred to spirits : — " from them and their motions principally proceed rarefaction, colliquation, con- coction, maturation, putrefaction, vivification, and most of the effects of nature;" " for tangible parts in bodies are stupid things, and the spirits do, in effect, all." (Natural History, cent. i. 98.) — In fact, some authors believe in three souls — the vegetable, sensible, and natural — for vegetables, brutes, and man ; those which have the second having also the first, and those who have the third having all three. Paracelsus believed in four. These old writers, in providing a spirit for every thing, were more consistent than the moderns, who require it for only life and mind ; because a subtle fluid or spirit is quite as necessary to explain the <( arrangement of saline particles into the regular form, of a beautiful crystal. All these notions still exist among the vulgar ; and the last remaining among the better informed, though it too is rapidly dying away, relates to mind. Those who upbraid others for refusing their assent to this hypothesis, may recollect that Anaxagoras and many more were accused of atheism and impiety, because they denied that the heavenly bodies were animated and intelligent. Even in the last reign but one, the Newtonian doctrines were thought irreligious by the Hutchin- sonian sect, to which Bishop Home, the amiable writer on the Psalms, and Mr. Jones, the learned and ingenious writer in defence of the Trinity, belonged : and the Jesuits, in their edition of Newton, 1742, carefully disclaim all belief in his demonstration of the earth's motion, as this is decreed false by the Pope.
Materialist is as good a word as any other for branding those from whom we differ; but materialism in its true acceptation signifies the doctrine of no first ' cause, or that all has been produced ex fortuita atomorum collisione. The whole tenor of scripture implies that we are bodies endowed with certain properties ; and those passages from which our having a distinct immaterial substance is inferred, may be easily explained by the figurative style of the Bible, by the necessary adoption of the language of the times, and by the influence of the national opinions and prejudices of the writers on their modes of expression. With- out due allowance, we might deem it impious to deny that " the round world cannot be moved;" that the sun " pursues its course" round the earth; ( Galileo was imprisoned for doing so, and yet, said the sage to himself while in prison, " the earth does move" — epur si muove .•) that Naaman's leprosy (a condition of body) was a real substance, because we read that it left him and
46 MIND.
surance besides that of the gospel, which, they read, " has
"clave unto Gehazi;" that Adam "surely" (more properly "utterly," "to- tally," or " entirely") died on the very day he tasted the forbidden fruit; that the winds possessed sense, because Christ said, " Peace, be still ;" that the earth is square, because we twice read of its four corners (/set. xi. Rev. vii. ) ; and that Saul's melancholy, and the cases of insanity and epilepsy related in the New Testament, were possessions by demons, which are pronounced by St. Paul to be " nothing in the world." (See the Rev. Hugh Farmer's original and admirable works, especially his Essays on the Demoniacs of the New Testament, and on Christ's Temptation.) Without due allowance, what absurdities might not be inferred from Christ's use of the word heart ? But the most enlightened divines allow us at present to follow Bacon's advice, and to read the Bible, not as a work of philosophical instruction, but of the revelation of religious matters beyond our knowledge, v. c. to learn from Genesis only how the world was created by God, and to study geology without reference to Moses. " The expressions of Moses are evidently accommodated to the first and familiar notions derived from the sensible appearances of the earth and heavens ; and the absurdity of supposing that the literal interpretation of terms in Scripture ought to interfere with the advancement of philosophical enquiry, would have been as generally forgotten as renounced, if the oppressors of Galileo had not found a place in history." A Treatise on the Records of the Creation, &c., by J. B. Sumner, M. A., Prebendary of Durham, &c. now Bishop of Chester, 3d edit. 1825, vol. i. p. 327. We may, therefore, learn the miracle of the resurrection from the gospels, and enjoy our own opinions respecting matter and spirit, body and soul, which, as relating to our nature, are objects of physical enquiry, and therefore not of revelation, any more than astronomy or geology. The writer of the celebrated Apology for the Bible says, " when I went to the University, I was of opinion, as most schoolboys are, that the soul was a substance distinct from the body, and that when a man died, he, in classical phrase, breathed out his soul, animam expiravit ; that it then went I knew not whither, as it had come into the body, from I knew not where nor when, and had dwelt in the body during life, but in what part of the body it had dwelt I knew not." — " This notion of the soul was, without doubt, the offspring of prejudice and ignorance." — " Believing as I do in the truth of the Christian religion, which teaches that men are accountable for their actions, I trouble not myself with dark disquisitions concerning necessity and liberty, matter and spirit ; hoping as I do for eternal life through Jesus Christ, I am not disturbed at my inability clearly to convince myself that the soul is or is not a substance distinct from the body." — Anecdotes of the Life of Bishop Watson, p. 14. sqq.
" Well indeed is it for us," says a liberal writer in the Quarterly Review, on the subject of geology, " that the cause of revelation does not depend upon questions such as these ; for it is remarkable that in every instance the controversy has ended in a gradual surrender of those very points which were at one time represented as involving the vital interests of religion. Truth, it is certain, can- not be opposed to truth. How inconsiderate a risk, then, do those advocates run, who declare that the whole cause is at issue in a single dispute, and that the sub-
MIND. 47
brought life and immortality to light. z They should reflect that the belief of an immaterial substance removes no imagined dif- ficulty, as it is the peculiar doctrine of scripture, in distinction to that of most heathen philosophers and people a, that the resurrec- tion will be positively of body, — that in our flesh we shall see God b, and that therefore our minds, according to the scripture doctrine, must appear as much a property of body hereafter as at present.0
Only this — the Christian — account of a future state is reason-
stance of our faith hangs upon a thread — upon the literal interpretation of some word or phrase, against which fresh arguments are springing up from day to day ! " 1823, April, p. 163.
The Theory of Religion, by the learned, able, and enlightened Bishop Law, already quoted, deserves to be read by every one, as proving that by the words soul and spirit, no immaterial, immortal principle in man is meant, but merely person, the superior and inferior mental faculties, living creature, &c. ; by death, a total cessation of existence ; by the life hereafter, a second bodily existence. It is to this admirable divine that Paley dedicates his Principles of Moral and Political Philosophy, and says — " Your Lordship's researches have never lost sight of one purpose, namely, to recover the simplicity of the Gospel from beneath that load of unauthorised additions, which the ignorance of some, and the learning of others ; the superstition of weak, and the craft of designing men, have (unhappily for its interest) heaped upon it. And this purpose, I am convinced, was dictated by the purest motive ; by a firm, and, I think, a just opinion, " that whatever ren- ders religion more rational, renders it more credible : that he who, by a diligent and faithful examination of the original records, dismisses from the system one article which contradicts the apprehension, the experience, or the reasoning of mankind, does more towards recommending the belief, and, with the belief, the influence of Christianity, to the understandings and consciences of serious en- quirers, and through them to universal reception and authority, than can be effect- ed by a thousand contenders for creeds and ordinances of human establishment."
For an account of all the hypotheses that have been taught upon life and mind, see An Enquiry into the Opinions, ancient and modern, concerning Life and Or- ganisation. By John Barclay, M.D., Edinb. 1822.
z 2 Timothy, i. 10.
a " Errant exsangues sine corpore et ossibus umbrae." — Ovid. Metam. iv.
b Job.
c It is the doctrine of the Church of England, that all men shall rise with their bodies* Enoch and Elijah are represented to have been translated bodily. Nay, our church has so little of this horror of matter, that it declares that Christ, " the very and eternal God" (Article ii.), ascended into heaven, and there sits, with " his body, vfithjlesh, bones, and all things appertaining to the perfection of man's nature. ' ' Article iv.
48 MIND.
able. The heathen doctrine was grounded on the supposed in- herent immortality of a supposed substance distinct from the body. The Christian doctrine teaches the resurrection of what we obvi- ously are — bodies, and that through a miracle of the Almighty. d
d Respecting a difficulty which may present itself to the conceptions of some Christians, but which the miraculousness of a future existence, I think, should re- move, I may quote Paley's sermon on the state after death. He concludes,
" That it is a question by which we need not be at all disturbed, whether the bodies with which we shall arise be new bodies, or the same bodies under a new form:
" For 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 un- doubtedly very great, hinder us from being the same, to ourselves and in ourselves, and to all intents and purposes whatsoever." — Sermons on several Subjects, by the late Rev. W. Paley, D.D. serm. 2. p. 96. These are a small system of divinity, and, having been bequeathed by him to his parishioners, probably contain his mature convictions.
4-9
II. SPECIAL PHYSIOLOGY.
CHAP. I.
HUNGER, THIRST, AND FOOD.
THE solid and fluid substances, taken into the mouth to repair the losses of the system, are termed food and drink; or both are comprised under the word food.
The desire for the former is called hunger or appetite, and for the latter, thirst.
" 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 abundance, — of the saliva and gastric juice, but to an acrimony which they acquire when food is not taken in proper time."
If hunger arise from merely a sense of vacuity in the stomach, why should it be increased by the application of cold to the sur- face, and instantly by 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, cannot be greater than the friction of the stomach against its contents immediately after a meal, when the organ is in great action, but at which time hunger does not exist.
Nor can the presence of the gastric juice explain the matter: because, as every one knows, no sensation arises in any other organ, which is not excrementory, from the peculiar stimulus of its natural fluid, and I presume that this is the stimulus intended, for the mechanical stimulus, from the bulk of tfye gastric juice, occurs equally from the presence of food, which does not excite hunger ; because, if the hungry stomach is evacuated by vomiting, as in sea-sickness, the appetite, when the sickness has ceased, is even greater than before ; and because hunger often ceases after a time, though the gastric juice still remains in the stomach, and is probably more abundant than ever.
E
50 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 sto- mach with a genera) 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 the substances with which they have distended their stomachs. Again, persons unable to obtain food in sufficient quantity lessen their hunger by swallowing any innutritious and indigestible matter. The circumstance giving rise to this opinion is the continuance of hunger although food be taken in abundance, in cases of scirrhous pylorus and enlarged me- senteric glands. Here, it is urged, the hunger continues, because the body receives no nourishment. But, in scirrhus of the pylorus, vomiting generally 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 expli- cable : but I do not know that a continued hunger commonly occurs in cases of scirrhous pylorus. In diseases of the mesen- teric glands there is, in fact, no obstruction to the course of the chyle. They are found permeable, according to Dr. Boekker, a German anatomist, and the continued hunger appears rather a part of the diseased state of the chylopoietic viscera. Besides, many cases of imperfect nutrition, from various causes, occur, without any increase of appetite : — and where there is an in- crease of appetite, the process of digestion seems to proceed with unusual rapidity, so that the stomach becomes empty sooner than in health. — In continued abstinence, although the system is daily more in want, hunger usually ceases after a few days, whether from the stomach falling into a state of relaxation, becoming dis- tended with wind, or from other circumstances.
If hunger arose from fatigue of the stomach, it should be greatest immediately after the laborious act of digestion, and gra- dually decrease ; but it on the contrary increases.
Were irritation the cause, hunger should be greatest when the stomach is filled with food.
HUNGER. 51
On the whole, hunger may perhaps be regarded as a sensation connected with the contracted state of the stomach.
It occurs when the stomach, being empty, must be contracted, and is increased instantaneously by a draught of cold liquid, which cannot but contract the stomach, and corrugate its inner coat : acids, bitters, and astringents have the same effect, and from their nature they may be supposed to act in the same way. Cold air applied to the surface increases it, and, in all probability, by a similar operation ; for the impression of cold upon the skin excites an attempt at evacuation in the urinary bladder, and, when all other means fail to induce the intestines to expel their contents or the uterus to contract after delivery, the affusion of cold water so frequently succeeds, that the omission of the practice in obsti- nate cases is highly censurable. It is diminished by heat and every thing which relaxes. Again, it ceases immediately that the stomach is filled and thus the organ dilated and all corru- gation 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. Distension of the stomach is universally acknowledged to be incompatible with hunger; whence the proverb, — " a full belly loathes the honey-comb."
The Otomacs during the periodical inundation of the rivers of South America, when the depth of the waters almost entirely pre- vents fishing, appease their hunger for two or three months by distending their stomach with prodigious quantities, a pound a day and upwards, of a fine unctuous, strong-smelling, yellowish-grey clay, slightly baked, and destitute of all organic substance, oily or farinaceous.* The savages of New Caledonia, in the Pacific Ocean, in times of scarcity, do the same by eating a friable lapis ollaris, consisting of equal parts of magnesia and silex, with a little oxide of copper. The wolves, rein-deer, and kids of Siberia, when pressed by hunger in winter, also devour clay or friable steatites. The Kamtschatkans sometimes appease their hunger by distending their stomach with sawdust, for want of something better.
Being, in this view, a sensation connected with a local state of the stomach, it will be affected not only by whatever affects this state, but by whatever affects also the sensibility to this state, and
a Humboldt, Tableaux de la Nature, t. i. They become so fond of it, that they take a little, even when well provided with sustenance, and are compelled to tie their children's hands to prevent them from geophagising.
E 2
52 THIRST.
therefore be subject to the common laws of sensation. Hence uncivilised tribes enable themselves to traverse large tracts with- out food by swallowing pills containing tobacco or opium. The pain of all excessive muscular contraction is lessened by pressure; whence the uneasiness of hunger is lessened by a belt fixed tightly over the stomach; and some Northern Asiatic tribes really place a band there, and lace it behind with cords drawn more tightly, according to the degree of the uneasiness. Thus, too, the state of the stomach remaining the same, hunger may diminish from the occurrence of other feelings 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 to pursuits of either intellect or passion, to delightful or painful sensation, all other feelings cease to be felt, although really violent; and frequently, from being unattended to, do not recur. Passions, however, and the narcotic pills of savages, may affect hunger, not only by increasing or di- minishing the sensibility to the state of the stomach, but by in- creasing or diminishing this state — the cause of the sensation.
As hunger appears to depend upon the local condition of the stomach, so does thirst more evidently upon that of the mouth and fauces. Every consideration renders it probable that thirst is the sensation of the deficiency 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 quantity or of great viscidity, or by carrying off the fluid when secreted, pro- duces thirst ; and vice versa. To be dry means to be thirsty, be- cause 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 re- peated in regard to it as was observed respecting hunger. Rage or terror dry up the mouth and throat, and cause violent thirst. Thirst is only momentarily assuaged by wetting the mouth and throat, because they presently grow dry again. Fluids must be swallowed to be effectual, that they may be absorbed and the part thus preserved moist by constant secretion.
" The necessity of obeying those stimuli is greater or less, ac- cording to age, constitution, and especially according to habit, and nothing can therefore be affirmed positively respecting its ur- gency ; but a healthy adult, in whom all the calls of nature are
STARVATION. 53
felt in their usual force b, cannot abstain from food a whole day without great prostration of strength, nor scarcely beyond eight days without danger to life."
Hippocrates says that most of those who abstain from food for seven days, die within that period ; and, if they do not, and are even prevailed upon to eat and drink, that still they perish.0 Sir William Hamilton, however, saw a girl, sixteen years of age, appa- rently not in bad health, who 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, had died on the fourth day, as the young are never so able to endure absti- nence.d A moderate supply of water lengthens life astonishingly. 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.6 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. f If the water is not swal- lowed, but imbibed by the surface or lungs, it may also prolong life. Fodere mentions some workmen who were extricated alive at the end of fourteen days from a cold damp cavern in which they had been buried under a ruin, f
In abstinence equally great imbecility of mind takes place as of body : extreme emaciation and oedema of the legs present a frightful spectacle ; urine may still be secreted, but the alvine discharge is greatly diminished, or suppressed altogether; the pain
b " Consult, among innumerable writers on long fasting, James Barthol. Bec- carius, Commentar. Instituti Bononiens. t. ii. p. 1.; and Flor. J. Voltelen, Me- morab. Apositice Septennis Hist. Lug. Bat. 1777, 8vo."
c De Carnibus.
d Phil. Trans, vol. Ixxiii. p. 191. sq.
e Medical Communications, vol. ii.
f Osservaz. intorno agli anim. viventi.
E Fodere, Medecine Legate, t. ii. p. 285. A hog, weighing about 160 Ibs., was buried in its sty, under thirty feet of the chalk of Dover Cliff, for 160 days. When dug out it weighed but 40 Ibs., and was extremely emaciated, clean, and white. There was neither food nor water in the sty when the chalk fell. It had nibbled the wood of the sty, and eaten some loose chalk, which from the appearance of the excrement had passed more than once through the body. (Linncean Transact. vol. xi. See London Med. Journ. vol. xxxv. 1816.) Pigs will not only eat coals, but keep in good condition upon them alone. Coals, however, are a vege- table substance. — Cuningham's Two Years in New South Wales, vol. i. p. 301.
E 3
54? STARVATION.
of hunger ceases in a few days11, probably from relaxation of the stomach through debility. But when hunger has ceased, though no food has been taken, weakness and sinking at the pit of the stomach are still felt.
Life may be supported for a certain time by nutriment intro- duced into the intestines. I lately attended a lady who, through obstruction of the oesophagus, attended by suppuration, did not swallow a particle of solid or fluid for six weeks, at the end of which she died. Three injections of milk, eggs, and wine, were employed daily. She passed a feculent soft evacuation in every twenty-four hours, and never felt the sensation of hunger.
A poor diet, even of vegetable matter, sometimes gives rise to symptoms of scurvy * ; and famine is soon attended by epidemic fever.
The torment of thirst increases until drink is procured or mois- ture applied to the surface or inhaled : inflammation of the mouth and throat, and intense fever, at length erisue.k
If abstinence is not forced upon the system, but is absolutely a part of disease, it may, like suspension of respiration in morbid states of insensibility !, and like immense doses of powerful medi-
h Among many other accounts of starvation, some of these facts may be seen in Captain Franklin's Narrative of a Journey to the Polar Sea, p. 465. sq. 427. London, 1823 j where the dreadful force of hunger is too truly illustrated. Our countrymen devoured their old shoes, and any scraps of leather they possessed, (pp. 418. 429. 438. 479.). The putrid spinal marrow left in bones, picked clean by wolves and birds of prey, was esteemed a prize, though its acrimony excoriated the lips ; the bones were also eaten up after being burnt (p. 426.) ; great part of a putrid deer was devoured on the spot (p. 421.) ; and to destroy, skin, and cut up a cow, was the work of a few minutes, after which the contents of the stomach and the raw intestines were at once devoured and thought excellent, (p. 407.) In the siege of Jerusalem and other ancient cities, we read of women driven by hunger to devour their offspring ; and Captain Franklin was assured, near the Saskatchawan, that men and women were then living, who had destroyed and fed upon the bodies of their own families, to prevent starvation in very severe seasons, (p. 51.)
1 See Sir George Baker's account of two women, in the Transact, of the College of Physicians, vol. ii.
k A horrid description of raging thirst will be found in the account of the black-hole of Calcutta. See Annual Register, 1758.
1 An example of the impunity with which a long exclusion of air may be borne, when the system is in a morbid nervous state, may appear to advantage by the side of similar illustrations of the deprivation of food. " The story of Ann Green," says the Rev. Mr. Derham, " executed at Oxford, Dec. 14. 1650, is still well
STARVATION. 55
cines in various diseased states, be borne with wonderful indiffer- ence ; and this occurs chiefly among females. But the most extraordinary case that I recollect, stated upon unquestionable authority, is that of a young Scotchwoman, who laboured under an anomalous nervous affection, and, excepting that on two occa- sions she swallowed some water, received no nourishment what- ever for eight years. She passed urine enough twice a week to wet a shilling, and for three years had no intestinal evacuation.10
remembered among the seniors there : she was hang'd by the Neck near half an Hour, some of her Friends thumping her on the Breast, others hanging with all their Weight upon her Legs, sometimes lifting her up and then pulling her down again with a sudden Jirk, thereby the sooner to dispatch her out of her Pain, as the printed Account of her informs us. After she was in her Coffin, being ob- serv'd to breathe, a lusty Fellow stampt with all his Force on her Breast and Stomach, to put her out of Pain. But, by the Assistance of Dr. Peity, Dr. Willis, Dr. Bathurst, and Dr. Clark, she was again brought to Life. I myself saw her many Years after, between which Time and the Date of her Execution she had, as I am inform'd, borne several Children." (Physico- Theology, \>. 1 56.} Her nervous insensibility appears from another writer, who states, that '•' she neither remembered how the fetters were knocked off, how she went out of prison, when she was turned off the ladder, whether any psalm was sung or not, nor was she sensible of any pain that she could remember. What is most remarkable is, that she came to herself as if she had awakened out of a sleep, not recovering the use of her speech by slow degrees, but in a manner altogether, beginning to speak just where she left off on the gallows." (Plott's History of Oxford.)
m Phil. Trans, vol. Ixvii. In a remarkable instance of imperfect abstinence during fifty years, the woman voided a little feculent matter like a piece of roll- tobacco, or a globule of sheep's dung, but once a year, and that always in March, for sixteen years. (Edinb. Med. and Phys. Essays, vol. vi.) It would be inter- esting to examine the changes induced in the air by the lungs and skin of such patients.
Pouteau mentions the case of one of his patients, a young lady thirteen years of age, who was affected with convulsions and insensibility at a certain period, generally every day, sometimes not quite so often, and great irritability of stomach, lived eighteen months, and grew more than two inches and a half, on syrup of capillaire and cold water. Here, the abstinence was not part of the disease, but the extraordinary state of the system enabled it to bear the abstinence. (Euvrea Posthumes, t. i. p. 27.
Still, many cases of abstinence have been impostures and exaggerations ; and I cannot illustrate this better than by quoting the case of Eue Fleigen, the Dutch prototype of our own Anne Moore of Tutbury. She contrived to deceive the world for fourteen years (from 1597 to 1611), pretending that she took no nourishment all that time, She had no nervous derangement to render food
E 4
56 VORACITY.
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 Drs. Percy and Laurent, in some measure from their own observation n, will form a good contrast to the Scotch girl. When a lad, he once swal- lowed 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 : he was no sooner relieved, however, 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 devouring 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 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 hopital ambulant at
unnecessary ; yet the minister and magistrates of Meurs made trial of her for thirteen successive days without detecting her imposture. Over her picture in the Dutch original are these lines : —
Muerae hsec quam cernis decies ter sexq ; peregit Annos, bis septem prorsus non vescitur annis Nee potat, sic sola sedet, sic pallida vitam Ducit, et exigui se oblectat floribus horti.
Thus rendered in the English translation —
This maide, of Meurs 36 yeares spent 14 of which she tooke no nourishment Thus pale, and wan she sits sad and alone A garden 's all shee loves to looke upon.
An Apologie or Declaration of the Power and Providence of
God. By George Hakewill. 1630. fol.
Respecting Anne Moore, see Dr. Henderson's Examination, &c. * Dictionnaire des Sciences Medicates, art. Homophage; where the dissection of another polyphagus is given, whose stomach was found to have been made neither more nor less than a collection of marine stores. See also Percy's Memoire sur If Polyphage, in the Journal de Medecine, Brumaire, An xii.
VORACITY. 57
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 swallow 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 contrived 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, and was readmitted into the hospital to be cured of his hunger. Being no longer a novelty, he excited less in- terest, and felt it necessary to have recourse to sheepfolds, poultry-yards, private kitchens, slaughter-houses, and by-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 Ver- sailles, wasted, no longer voracious, and labouring under a puru- lent diarrhoea ; and he soon died, aged twenty-six. The body immediately became a mass of putridity. During his life he was always offensive, hot, and in a sweat, especially at intervals. His breath rolled off like steam, and his dejections were constantly very 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
58 VORACITY.
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 excessively large cavity, and the intestines running, without a single convolution, but with merely a gentle sigmoid flexure, to the anus. A large pylorus, or a very depending position of it, have been found in other cases. We thus learn the common causes of constitutional vora- ciousness, and obtain an additional reason for referring hunger to the want of distention of the stomach : — a great quantity of food is required to Jill 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 suffice where the stomach is very large, as the extraordinary quantity of food can- not be demanded for nourishment, — when food enough for support is taken, hunger should cease. But hunger continues till the sto- mach is filled, and the prodigious collection in the case of Tarare was disposed of by abundant stools, sweating, and copious pul- monary 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 cor- poration 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 had swallowed nineteen large clasp-knives at different times, having found in a drunken fit that he could get one down his throat for a wager0 : yet in him the appetite and capacity of stomach were not augmented. Knife and stone eaters are seen in all countries.
Some great eaters are prodigies of strength; as Milo, who killed
0 Several pieces of the knives are preserved in the Museum of Guy's Hospital, and an account of the case may be found in the Med. Ckir. Trans, vol. xii.
There is a collection of cases of extraordinary swallowing from Galen, Vesalius, Pare, &c.,in Shenkius, Observationes Medicce, lib. iii.
A polyphagus at the Jardin des Plantes, who once ate a lion which had died there of some disease, and at last died himself of eating 8lbs. of new bread, most originally conceived, being all for the belly, that animals might be classed accord- ing to their excrement, and actually made a collection of such stores, upon which he would descant most eloquently. Diet, des Sc. Med., Cas. Rares, p. 199.
VORACITY. 59
an ox with a blow of his fist, and 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 sucking-pig, and sixty pounds of plums, stones and all, and could carry four men a whole league upon his shoulders.
Voracity is of course sometimes, like depraved appetite, as in chlorosis and pregnancy, but temporary, and referable 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 exacerbations 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,
" cibus omnis in illo,
Causa cibi est, seraperque locus fit inanis edendo,"
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, and was too soon empty again.
To show how some animals differ from us in the demand for food, I may mention that the ant-lion will exist without the smallest supply of food, apparently uninjured, for six months ; though, when he can get it, he will daily devour an insect of his own size. A spider has lived without food under a sealed glass for ten months, and at the end of that time appeared as vigorous as ever. Reptiles have often lived upwards of a century enclosed in trees or stones.
On the other hand, herbivorous larvee, as caterpillars, (for in- sects are carnivorous, herbivorous, and omnivorous, like their superiors,) will eat twice their weight of food daily. r
P Ovid's account of Erisichthon is verified in many histories of voracity : —
" Ipse suos artus lacero divellere morsu
Ccepit; et infelix minuendo corpus alebat." Metam. lib. viii,
<i Transactions of the Royal College of Physicians, London, vol. v.
See also Phil. Trans. Papers read 1745; and Abridgment, vol. iii. p. 111.
r Kirby and Spence, Entomology, p. 398. sq.
60 FOOD.
" Although thirst is a violent desire, drink appears not very necessary to life and health ; for many warm-blooded animals — mice, quails, parrots, &c. — do not drink at all ; and some indivi- duals of the human species have lived in perfect health and strength without tasting liquids."5
Sauvages mentions a member of the Academy of Toulouse who never thirsted, and passed whole months of the hottest summer without drinking ; and a woman who passed 40 days without liquids or thirst. l
" It has been disputed whether our food, by which we satisfy these stimuli, is derived more advantageously, and the more con- sistently with nature, from the animal or from the vegetable kingdom. u
" Some contend that man is herbivorous, from the shape of his teeth Y, the length of his intestines y, the difference between the structure of the small and large intestines, and from the cells of the colon, &c. Rousseau ingeniously urges the circumstance that woman is naturally uniparous and provided with two breasts.2 To these arguments it may be added, that some men have rumi- nated,— a power peculiar to herbivorous animals*, and that tame
s " See G. Baker, Med. Transact, published by the Coll. of Physicians in London, vol. ii. p. 265. sq."
1 " Nosol. Method, t. i. p. 770.
See also Eph. Nat. Cur. c. v. and vi. p. 30."
u " J. W. Neergaard, Vergleichende Anatomic und Physiologic der Verdauungs- werkzeuge der Saiigethiere und Vogel. Berlin, 1806, p. 244."
* " Gassendi, Letter to J. Bapt. v. Helmont. Opera. Florence, 1727, fol. t. vi. p. 17. Al. Monro, senr. Essay on Comparative Anatomy, p. 17."
y « J. Wallis, Phil. Trans. No. 269."
z " Sur rOrigine de flnegalite parmi les Hommes, p. 196. sq."
a A striking instance of this occurred at Bristol. A man twenty years of age had, as long as he could remember, chewed his food a second time, after swallow- ing it. The process began in a quarter of an hour if he had taken liquid at his meal — later if he had not : and, after a full meal, lasted about an hour and a half. What had passed down first, always came up first. Before the second chewing, his food appeared to 1'e heavy in the lowest part of his throat : after it, " the food passed clean away." If he ate a variety, " that which passed down first came up first." He found the taste of the food on its return to be chewed rather plea- sant'er than at first. " If this faculty left him it signified sickness, and he was never well till it returned." His father had sometimes ruminated slightly. (Phil. Trans, Abridgment, vol. iii. p. 110. sq.)
RUMINATION. 61
vegetable feeders are easily accustomed to animal food ; where- as carnivorous animals, excepting the dog, can very seldom be brought to feed on vegetables.
" The arguments of those who, with Helvetius b, regard man as carnivorous, are derived from the conformation of his stomach, the shortness of his ca3cum, &c.
" More careful observation, however, proves that man is not destined for either kind of food alone, but for both. His teeth, particularly the molaresc, and the peculiar structure of his intes- tines just alluded to, hold a middle rank between the same parts in the ferae and in herbivorous animals." 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 scissors, and being adapted for lacerating. In the herbivorous, the surface of the molares is horizontal or oblique, adapted for grinding. As the food of herbivorous animals re- quires more preparation before it becomes the substance of the animal, their stomach is adapted to retain it for a length of time. The oesophagus opens nearer the right extremity of the stomach, and the 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 among insects, are generally shorter, and have fewer valvulse conniventes, and in some instances no caecum.
Blumenbach has seen four examples of this kind : in two the process was compulsory, in two it was optional. These subjects also were males, and had a real gratification in ruminating. Comparative Anatomy, translated by Messrs. Lawrence and Coulson, 2d edit. p. 88. A case of human rumination, in a man, has lately been seen at the London Hospital. London Medical Gazette, June 23, 1832.
b " De VHomme, t. ii. p. 17."
c " The opinion of Broussonet is singular. He thinks the human molares closely resemble the teeth of herbivorous animals, and at the same time regards the incisores and canini as allied to those of the carnivorous tribes : and, after comparing the number of the molares with that of the other teeth, concludes that the quantity of vegetable food intended for man is to the quantity of animal food as 20 to 12.
" But on this calculation it follows, that infants, who have four molares only in each jaw, are destined to consume a larger portion of animal food than adults, since the proportion of the molares to the other teeth is in them as 8 to 12."
E 7— F
62 FOOD. _
" The mode in which the condyles of the lower jaw are articu- lated with the temporal bones, demonstrates his destination for both kinds of food in the most striking manner." 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 pre- vented, as motion upwards and downwards 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. Its nature in man is explained at the beginning of the next chapter.
" 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.
" Man is by far the most omnivorous of all animals, capable not only of feasting on luxurious combinations 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 present live on vegetables only, as the tubera of solanum (potatoes), chestnuts, dates, &c. The first families of mankind most probably subsisted for a long period merely on fruits, roots, corn, and pulse.d
" The nomadic Moors have scarcely any other food than gum senega':
d " Consult Heyne, Opuscula Academ. vol. i. p. 366. sq." e « Adamson, Mem. de FAcad. des Sc. de Pans, 1778, p. 16." 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 above a thousand persons subsisted for two months. (Hasselquist, Voyages and Travels in the Levant, p. 298.) Yet Dr. Magendie says he finds that dogs perish if fed only with gum or sugar, olive oil, butter, and similar articles, regarded as nutritious, which contain no azote. (Annales de Chimie et de Physique, voh iii. p. 66. 1816.) But although such substances be alone unable 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 render it probable 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
FOOD. 63
" The inhabitants of Kamischatka and many other shores scarcely any other than fish.
" The shepherds in the province of Caraccas in South America,, on the banks of the Orinoko f, and even the Morelachs s in Eu- rope, live almost entirely on flesh.
" Some barbarous nations devour raw animals. This cannot be denied to have formerly been the case with the Samojedes h, the Esquimaux1, and some tribes of South America.k
" Other nations are no less remarkable in their drink.
" The inhabitants of many intertropical islands, especially in the Pacific Ocean, can procure no sweet water, and instead of it drink the juice of cocoa-nuts.
" Others take only sea-water; and innumerable similar facts clearly prove man to be omnivorous."
It appears that matter, as in the case of water, which has never belonged to an animated system, is calculated to afford nourish-
made a pigeon live on flesh, and an eagle on bread. (Experiences sur la Diges- tion, c. Ixxiv. c. Ixxv.) If fresh- water mollusca are put at once into sea water, or sea-water mollusca into fresh water, they perish ; but if the change is gradually made, they live very well. ( AnncJ.es de Chimie et de Physique, vol. ii. p. 32. 181 6. ) A spider has fed upon sulphate of zinc. (Thomson's Anncds of Philosophy, vol. xii. p. 454.) We have seen that the Otomacs eat little else some months of the year than large quantities of earth, and that some brutes devour earth. I may here add that not only the Otomacs are so fond of it, as, when well supplied with food, to take a little, but that many nations of the torrid zone have a propensity to geophagism. The negroes of Guinea, the Javanese, the New Caledonians, and many South American tribes, eat clay as a luxury ; and the Guajeroes, on the west of Rio da la Hache, carry a little box of lime as sailors do a tobacco-box. German workmen at the mountain of Kiffhonser spread clay instead of butter on their bread, and call it stein butter, and find it very satisfying and easy of diges- tion. The Otomacs do not suffer by the practice, but in some tribes the people grow sick and thin by indulging too freely in this luxury. Africans who geo- phagised with impunity at home on a yellow clay, severely suffer from it in the West Indies. (See also Dr. John Hunter, Diseases of the Army in Jamaica, p. 248. sqq.) The red clay eaten in Java destroys the appetite and wastes the body.
f " Fil. Salv. Gily, Saggio diStoria Americana, vol. iv. p. 120." E " Gius. Ant. Pujati, Reflessioni sul Vita Pitagorico. Feltri, 1751, 4to." h *' De Klingstaedt, Mem. sur les Samojedes et les Lappons. 1762, 8vo." 4 " Curtis, Phil. Trans, vol.lxiv. p. ii. p. 381. 383."
* " J. Winter, in Hakluyt's Principal Navigations of the English Nation, vol. iii. p. 751."
64 FOOD.
ment 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 live chiefly on such, and will indisputably live for a time with facility on them alone, and some even if merely suspended in the air1 (carbonic acid is, indeed, the great nourishment of all vegetables), but even- tually will not thrive and perfect their seed, unless animal or vegetable remains exist in the soil ; whence the necessity of this kind of manure, which must have likewise been so changed by putrefaction that its carbon has formed a compound resembling the extractive principle and thus capable of solution in water.™ It has been contended that some animals, as fish, and that some vegetables, readily subsist, growing equally with others, and per- fecting their seed or ova, on simple water ; but the experiments in support of this assertion are not at all decisive.0 None of these statements are affected by the derivation of gaseous sub- stances from the surrounding air or water, by animals or vege- tables.
The articles of diet generally employed by every nation and class of society are much determined by the facility with which they are procured. Generally, too, animal food is preferred in cold climates, and vegetable in warm : a mixture, however, of the two is usually preferred to either exclusively, and appears better suited to our necessities. Animal food is chiefly muscle and fat, milk and eggs ; vegetable food, chiefly seeds and roots, fruits and leaves, with more or less of the stalks. These articles, which are rendered more or less masticable or digestible by heat, are previously subjected to high temperatures in various ways ; and as many saline and aromatic substances are taken, not so much for their nutritive qualities and their undoubted assistance when the stomach is weak or chiefly vegetables are eaten, as for their sapid qualities, and since the admixture of these, and the combination
1 Two fig plants ( Ficus austraUs and Ficus elastica) have continued to send out shoots and leaves, the former for eight, the latter for fourteen, years, sus- pended in the hot houses of the Botanical Garden of Edinburgh. — Elements of Chemistry, by Dr. Turner, Professor of Chemistry in the University of London, 1833. p. 862. sq.
171 Mould consists principally of carbon, combined with a little oxygen and hydrogen, and, if it be animal, with also a little azote, together with the usual saline ingredients of organised substances.
n Full information on this subject will be found in Dr. Thomson's System of Chemistry, book iv. ch. 3. sect 2.
FOOD. 65
of various nutritive substances together, often highly increase the exquisiteness of taste and flavour, the culinary art is cultivated not only for health, but also for luxury.
The chief proximate principles of animal food are fibrin, albumen, gelatine, oil, and sugar ; of vegetable, gluten, fecula, mucilage, oil, and sugar. My not less excellent than distinguished friend, Dr. Prout, in the paper which was honoured with the Cop- ley medal of the Royal Society °, reduces all the articles of nourishment among the higher animals to three classes: the sac- charine, oily, and albuminous. The first comprehends sugars, starches, gums, acetic acid, and some other analogous principles; the second, oils and fats, alcohol, &c. ; the third, fibrin, gelatine, albumen, and caseum or the curd of milk, with vegetable gluten, so abundant in wheat. He has favoured me with the following remarks, which are chiefly an abstract from a work on digestion, commenced by him in 1823, but not yet published.
" Observing that milk, the only article actually furnished and intended by nature as food, was essentially composed of three ingredients, viz. saccharine, oily, and curdy or albuminous matter, I was by degrees led to the conclusion that all the alimentary matters employed by man and the more perfect ani- mals might, in fact, be reduced to the same three general heads ; hence I determined to submit them to a rigorous examination in the first place, and ascertain, if possible, their general relations and analogies. An account of the first of these classes, viz. the saccharine matters, has been published in the Philosophical Transactions, and the others are in progress. The characteristic property of saccharine bodies is, that they are composed simply of carbon united to oxygen and hydrogen in the proportions in which they form water; the proportions of carbon varying in different instances from about 30 to 50 per cent. The other two families consist of compound bases (of which carbon constitutes the chief element) likewise mixed with and modified by water, and the pro- portion of carbon in oily bodies, which stand at the extreme of the scale in this respect, varies from about 60 to 80 per cent.; hence, considering carbon as indicating the degree of nutrition, which, in some respects, may be fairly done, the oils may be regarded in general as the most nutritious class of bodies; and the general conclusion from the whole is, that substances naturally containing
0 Phil. Trans. 1827. F 3
66 FOOD.
less than 30 or more than 80 per cent, of carbon are not well, if at all, adapted for aliment.
" It remains to be proved whether animals can live on one of these families exclusively ; but at present experiments are de- cidedly against this assumption, and the most probable view is, that a mixture of two at least, if not of all three, of the classes of nutri- ment, is necessary. Thus, as has been stated, milk is a compound of this description, and almost all the gramineous and herbaceous matters employed as food by animals contain at least two of the three — the saccharine and glutinous or albuminous. The same is true of animal aliments, which consist, at least, of the albumin- ous and oleaginous : in short, it is, perhaps, impossible to name a substance employed by the more perfect animals as food, which does not essentially constitute a natural compound of, at least, tuoy if not of all three, of the above three great classes of aliment* ary matters.
" But it is in the artificial food of man that we see this great principle of mixture most strongly exemplified. He, dissatisfied with the productions spontaneously furnished by nature, culls from every source, and, by the power of his reason, or, rather, his in- stinct, forms, in every possible manner, and under every disguise, the same great alimentary compound. This, after all his cooking arid art, how much soever he may be inclined to disbelieve it, is the sole object of his labour, and the more nearly his results approach to this, the more nearly they approach perfection. Thus, from the earliest times, instinct has taught him to add oil or butter to farinaceous substances, such as bread, which are naturally defective in this principle. The same instinct has taught him to fatten animals, with the view of procuring the oleaginous in con- junction with the albuminous principle, which compound he finally consumes, for the most part in conjunction with saccharine prin- ciples in the form of bread or vegetables. Even in the utmost refinements of his luxury and in his choicest delicacies, the same great principle is attended to, and his sugar and flour, his eggs and butter, in all their various forms and combinations, are nothing more nor less than disguised imitations of the great alimentary prototype, milk, as presented to him by nature." P It may be
f Consult also Dr. Prout's admirable Bridgewater Treatise, just published, in which will be found this and much other highly original and valuable matter.
FOOD. €7
worth reflecting, that children are particularly fond of saccharine substances, and dislike the oleaginous, at least fat.
More or less of common salt exists in the food of all animals. It is equally desired by the greater number, and many traverse im- mense tracts and encounter great difficulties to obtain it. Dr. Prout, I may mention, considers it, or the muriatic acid or chlo- rine which it affords, of the highest importance in the animal economy. How far a certain supply of other substances, as earths, metals, phosphorus, &c. from without is necessary, is not accurately known. Water is indispensable to vegetables and most animals.
Dr. Prout considers it as a general rule, subject, indeed, to many exceptions, that the food of organised beings is substances lower than themselves in the scale of organisation. Vegetables live chiefly on water and gases ; and the animal or vegetable matters which also are their food, certainly must be in a state of entire decomposition. Some animals eat organised matter partly decomposed. The greater part live on animal or vegetable matter unchanged ; and the animal matter is usually obtained from animals inferior in bulk or intelligence, — from animals with inferior powers of resistance. Man eats both animal and vegetable matter undecomposed, of infinite variety, all derived necessarily from beings inferior to himself. q
*i M. Rastail, in a work published last year, at once profound, bold, and original, and containing the substance of various memoirs printed during the previous six years, entertains views very similar to those of Dr. Prout, though much more imperfect. He states, that proximate principles must be combined to become nutritious — that neither sugar nor gluten alone affords support, but that when combined they are alimentary. He offers the same objections to Dr. Magendie's conclusions respecting gum and other unazotised substances, which I have offered for many years. — Nouveau Systeme de Chimie Orgardqtie, fondSsurdes Methodes Nouvelles d' Observation. Par F. V. Rastail. Paris, 1833.
F 4
68
CHAP. II.
MASTICATION AND DEGLUTITION.
THE food taken into the mouth, if solid, is reduced to a pulp by trituration and mixture with the fluids, and then passed into the stomach. The first process is termed mastication or chewing ; the second, deglutition or swallowing.
" The lower jaw is the chief organ of mastication, and is sup- plied, as well as the upper, with three orders of teeth.
" With incisores, generally a scalpriform, for the purpose of biting off small pieces, and not placed in the lower jaw, as in other mammalia, more or less horizontally, 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 beyond the rest, nor are placed alone, but lie closely and in regular order with the others. ,:<;i>
«' With molares of various sizes, adapted for grinding, and dif-
a " I say generally : for, without alluding to particular examples of their obtuseness, I may remark that I have found the crown of the incisors thick and obtuse in the skulls of most mummies. And since the more remarkable for this variety have resembled, in their general figure and appearance, the singular and never-to-be-mistaken physiognomy of the ancient Egyptians, observable in the idols, sarcophagi, and statues of ancient Egypt, it is probable that this peculiar form of the teeth, whether owing to diet or whatever else, was peculiar to the ancient Egyptians, and may be regarded as a national mark, or even as a cha- racteristic by which true ancient mummies may be distinguished from those of late formation."
" I have written at large on this subject in the Philos. Trans. 1794. P. II. p. 184."
MASTICATION AND DEGLUTITION.
69
fering conspicuously from those of other mammalia, by possessing gibbous apices excessively obtuse.
The four central teeth in both jaws are the incisores : the outer one on each side in both is the canine : the five outermost on each side in both are the molares.
a, belly of the digastric arising at the root of the mastoid process of the tempo- ral bone : b, belly arising below the sym- physis of the lower jaw: c, tendon in which each ends : d, os hyoides, into which the tendon is inserted. If the os hyoides is fixed, the inner belly can lower the jaw : if the jaw is fixed, the os hy- oides can be raised, e, genio-hyoideus : f, mylo-hyoideus.
" 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, has easy motion in every direction." In other words, the condyles of the lower jaw are prevented from descending very deeply into the glenoid cavity ; and are con- fined to vertical movements, by a cartilage which is hollow on each surface, and moveable, and permits the condyle to move from the glenoid cavity to a tubercle which stands before this, and thus to acquire still greater mobility.
a, outer part of the lower jaw : by its condyle, pulled down from the glenoid cavity to show the joints : c, inter- articular fibro-cartilage form- ing two menisci : rf, upper synovial membrane : e, lower synovial membrane : f, zygo- ma, : g, mastoid process : k, sty- loid process. The three other figures are a superior, an in- ferior, and a lateral, view of the interarticular cartilage. • £,
The digaster, assisted somewhat by the genio-hyoidei and
70
MASTICATION AND DEGLUTITION.
mylq-hyoidei 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 ex- ternal pterygoid. - " The latter can also draw it forwards.
" Substances are retained, directed, and brought under the action of the teeth, by the buccinator, and by the tongue, which is very flexible and changeable in form.
a, temporal muscle, inserted by a tendon into the coronoid process of the lower jaw : 6, masseter arising from the zygoma, and inserted into the angle of the lower jaw : c, buccinator, or great muscle of the cheek, the action of which is to lessen the cavity of the mouth, and draw the angle of the lips backwards. The mere inspection of the other muscles shows their action, d, the parotid gland : e, its duct : /, a portion of the sub-maxillary gland uniting with the parotid.
a, external pterygoid, arising from the pterygoid process and zygomato-temporal sur- face of the sphenoid bone, and the tuberosity of the os palati, and inserted into the front of the neck of the condyle of the lower jaw, and interarticular cartilage. b, internal pterygoid, arising from the pterygoid fossa of the sphe- noid bone, and from the pterygoid processes of the palate bone, and inserted within the angle of the lower jaw.
MASTICATION AND DEGLUTITION. 71'
"During mastication, there occurs a flow of saliva b, which is a frothy fluid," consisting, according to Berzelius, of Water - .x+b: i.'>tf h;
A peculiar animal matter i&jpHj ;/;
MUCUS - - !{><»IC 'fO^iji B.^.-'i; ;,!>;
«i . ; . • Alkaline muriates - vrt *,'_• ? ^ . *y *t *«•;
Lactate of soda and animal matter >J«M
Pure soda . '' -y* r:;.' .r*r: ' - - h'V« fiQisfc;
1000.0C
What Berzelius calls mucus, Dr. Thomas Thomson and Dr. Bos- tock regard as albumen. This mucus is insoluble in water, and, when incinerated, but not before, yields a large .portion of phos- phate of lime.d
According to an examination by Tiedemann and Gmelin, saliva, mixed with more or less mucus, consists of —
A peculiar matter termed salivary; osmazome; mucus; — all essential to its composition :
Sometimes a little albumen :
A little fatty matter, united with phosphorus :
Potass, united with acetic, phosphoric, sulphuric, hydro-chloric, and sulpho-cyanic acid ; — all soluble salts :
A large quantity of phosphate, and a smaller of carbonate, of lime ; a minute quantity of magnesia ; - — all three insoluble.
The solid contents amount to about -fa per cent. The alkaline properties of saliva were before ascribed to a free alkali, and that alkali was supposed to be soda. In the dog the alkali is soda, very little potass being discoverable.6
*M. Rastail remarks, that whatever other" persons examine the saliva will have still other results, as different substances are mixed in it at different times, and names are given to the mixture the elements of which are not determined. He discovers that the
b " J. Earth. Siebold, Historia Systematis Salivalis. Jen. 1797. 4to." c J. Berzelius, Medico- Chirurgical Transactions, vol. iii. p. 242. d The tartar of the teeth arises from its gradual decomposition upon them, and consists, according to Berzelius, of
Earthy phosphates - ' - 79.0
Undecomposed mucus - - 12.5
Peculiar salivary matter - \-, - 1-0 Animal matter soluble in muriatic acid - 7.5
«' • 100.0
* Die Verdauung nach Versuchcn, &c. By Fred. Tiedemann and Leopold Gmelin, Professors in the University of Heidelberg.
72 MASTICATION AND DEGLUTITION.
mucous membranes are constantly shedding and renewing, like the epidermis, from their ceils successively shrivelling ; and that saliva taken before breakfast, and examined with the microscope, presents such membranous particles, which are the animal matter mentioned by chemists, and soluble only in hydrochloric (muriatic) acid. He adds, that, besides muriate of soda, it contains muriate of ammonia; and as to the lactates, he proves that lactic acid is only a combination of albumen and acetic acid. The quantity of ammonia, salts, and membranous particles varies, and is much greater before breakfast. He considers the saliva to be an albu- minous solution, mixed with membranous fragments and salts, which affect its solubility in water/
" The saliva flows from three orders of conglomerate glands, placed laterally and interiorly with respect to the lower jaw.
" The parotids^ are the largest, -and pour forth the saliva behind the middle molares of the upper jaw, through the Stenonian ducts :h
" The submaxillary *, through the Whartonian : k
" The sublingual l, — the smallest, through the numerous Ri- vinian. m
a, parotid gland : b, parotid duct : c, submaxillary gland : d, submax- illary duct : e, sublingual gland.
f 1. c., p. 454. sq.
8 '* See De Courcelles, Icones Musculorum Capttis, tab. i. g. h."
h " Stenonis, Observationes Anqtomic(£, p. 20."
1 " De Courcelles, 1. c. tab. n. 1. 1."
* " Wharton, Adenographia, p. 12O."
1 " De Courcelles, tab. v. g. g. g."
ln " Rivinus, De Dyspepsia. Lips. 1 678. 4to.
Aug. Fr. Walther, De Lingua Humana, ib. 1724. 4to."
MASTICATION AND DEGLUTITION.
73
" The excretion of saliva, amounting, according to the arbi- trary statement of Nuck «, to a pound in twelve hours, is aug- mented by stimuli and by mechanical pressure, or, if the term 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 ima- gination, as when the mouth waters during the desire for food.
" The mucus of the labial and buccal glands °, and of the
Inner part of lips. a a, labial glands : 6, buc- cal glands : c c, parotid ducts : d d, their orifices.
tongue, as well as the moisture which transudes from the soft parts of the mouth, is mixed with the saliva.
" 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 assi- milation.
" The mechanism p of deglutition, although very compli- cated, 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 curious and rather violent effort by the infundibulum of the pharynx, which is enlarged and in some measure drawn for- ward to receive it. The three constrictores <i muscles of the pharynx drive it into the oesophagus. These motions are all per-
0 " Nuck, Sialographia, p. 29. sq."
0 " De Courcelles, 1. c. tab. iv. e. e. e."
p " Fr. Bern. Albinus, De Deglutitione. LB. 1740. 4to.
P. J. Sandifort, Deglutitionis Mechanismus. Lugd. Batav. 1805. 4to."
1 " Eustachius, tab. XLII. fig. 4. 6.
Santorini, Tab. Posthum. vi. fig. 1. . B. S. Albinus, Tab. Muscular, xii. fig. 23, 24."
MASTICATION" AND DEGLUTITION,
formed in very rapid succession, and require but a short space of time.
*' Nature has provided various contrivances for opening and securing this passage.1"
« The important motion of the tongue is regulated by the os hyoides.
" The smallest particle of food is prevented from entering the nostrils or Eustachian tubes, by means of the soft palate8, which, as well as the uvula suspended from its arch, and whose use is not clearly understood, is extended by muscles of its own, and Closes those openings. l
" The tongue protects the glottis, for the larynx at the mo- ment 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." The glottis,
POSTERIOR VIEW.
LATERAL VIEW.
Posterior and lateral views of the throat, a, the tongue : b, palato-staphyline1 muscles, forming the uvula : c, epiglottis : d, larynx : e, pharynx : /, beginning of oesophagus : g, constrictor superior of pharynx turned back : h, constrictor medhis : i, constrictor inferior : j, posterior opening of nostrils : k, opening of Eustachian tube : I, genio-glossus muscle : ra, buccinator : n, orbicularis labi- orum : o, cavity of the nostrils.
r «' J. C. Rosenmuller, Icones Chirurgico-Anatomicce. Fasc. •!. Vinar. 1805.
foi."
* " Littre, MSm. de VAcad. des Sc. de Paris, 1718. tab. xv." 1 " Santorini, Tab. Posthum. iv— vi, fig. 2. •— and vn.
B. S. Albinus, Tab. Muscular, xii, fig. 11. 27, 28. V A. -' .'
MASTICATION AND DEGLUTITION./, 75
however, when sound, may be sufficiently closed by the transverse and oblique arytaenoid muscles, independently of the epiglottis. Dr. Magendie says that he saw two persons perfectly destitute of epiglottis, who always swallowed without difficulty." Targioni also met with one, and in that case neither deglutition nor speech was impaired. *
" Deglutition is facilitated by the abundance of mucus which lubricates these parts, and which is afforded not only by the tongue, but by the numerous sinuses y of the tonsils and muci- parous cryptae of the pharynx.
" The oesophagus, through which the food must pass pre^ viously to entering the stomach, is a fleshy canal, narrow and very strong, mobile, dilatable, very sensible, and consisting of coats resembling, except in thickness, the coats of the other parts of the alimentary canal.2
" The external coat is muscular, and possesses longitudinal and transverse fibres.
" The middle is tendinous, lax, and more and more cellular towards each of its surfaces, by which means it is connected with the two other coats.
" The interior is lined, like all the alimentary tube, with an epithelium analogous to cuticle, and is lubricated by a very smooth mucus.
" This canal receives the approaching draught or bolus of food, contracts upon it, propels it downwards, and, in the case of the bolus, stuffs it down, as it were, till it passes the diaphragm and enters the stomach."
Professor Halle observed in a woman, the interior of whose stomach was exposed by disease, that the arrival of a bolus of food in the stomach was followed by an eversion of the mucous membrane of the resophagus into it, as we notice in the case of the rectum when a horse has finished discharging its faeces.a
u Magendie, Precis Element. x Morgagni, xxviii. 13.
y " B. S. Albinas, Anotat. Acad. .1. m. tab. in. fig. 1; n." z " See Math. Van. Geuns, Verhandelingen van de Maatschappye te Haarlem^ t. xi. p. 9. sq.
" Jan. Bleuland, Observ. de Structura (Esophagi. LB. 1785. 4to." a Magendie, Precis Ettmentaire.
76
MASTICATION AND DEGLUTITION.
a, soft palate: b, anterior pillars of soft palate: c, poste- rior pillars of soft palate. The space between them is call- ed the fauces, d, uvula : e, upper part of trachea : f, reso- phagus, the upper part having been cut away to shorten the drawing: g, cardia: ht pylorus, the space between g and h be- ing the cavity of the stomach : i i, duode- num : k, hepatic duct: ly gall bladder: m, cystic duct : n, ductus communis choledo- chus, formed of the two : o, the opening of the choledochus into the duodenum : p, pancreatic duct; qt its opening into the duodenum, which here is distinct from that of the choledo- chus: r, jejunum : s, ilium : t, termin- ation of ilium in cae- cum : u, superior fold of valve of co- lon ; v, inferior of ditto : w, caecum : x, vermiform process : y y, colon: 2, rec- tum : 1, part of leva- tores ani : 2, anus.
77
CHAP. III.
DIGESTION.
" THE stomach is the organ of digestion. It exists, what cannot be affirmed of any other viscus, in, perhaps, all animals without exception ; and, if the importance of parts may be estimated in this way, evidently holds the first rank among our organs.
" The human stomach a resembles a very large leathern bottle, is capable, in the adult, of containing three pints and upwards of water, and has two openings.
" The superior, called cardia, at which the oesophagus, folded and opening obliquely, expands into the stomach, is placed to- wards the left side of its fundus.
" The inferior, at which the right and narrow part of the sto- mach terminates, is called pylorus, and descends somewhat into the cavity of the duodenum.
" 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 greater curvature in- clining downwards, while the pylorus, being directed upwards, forms, by doubling, an angle with the duodenum. b
" When full, the larger curvature is rolled forwards0, so that the pylorus lies more in a line with the duodenum, while the cardia, on the contrary, is folded, as it were, into an angle and closed.
" 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
a " Eustachius, tab. x. fig. 1,2, 3.
Ruysch, Thes. Anat. ii. tab. v. fig. 1.
Santorini, Tab. Posth. xi."
b " Vesalius, De c. h. Fabrica. L. v. fig. 14, 15." c «« Id. 1. c. fig. 2."
G
78
DIGESTION.
the seat of the extraordinary irritability of the stomach. It con- sists of strata of muscular fibres d, commonly divided into three orders, one longitudinal and two circular (straight and oblique), but running in so many directions that no exact account can be given of their course.
" The third is the chief membrane. It is usually termed nerv- ous, but improperly, as it consists of condensed cellular membrane, 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 ali- mentary canal), improperly called villous, is extremely soft, and in a manner spongy, porous, and folded into innumerable rugae0, so that its surface is more extensive than that of the other coats; it exhibits very small cellsf, somewhat similar to those larger cells which are so beautiful in the reticulum of ruminants.
" Its internal surface is covered with mucus, probably secreted in the muciparous crypts which are very distinct about the pylorus.
" The stomach is amply furnished with nerves ? from each nervous system, whence its great sensibility, 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 referable the influence of all passions upon the stomach, and of the healthy condition of the stomach upon the tranquillity of the mind. h
" The abundance and utility of the blood-vessels of the sto- mach are no less striking. Its arteries, ramifying infinitely upon the cellular membrane and glands, secrete the gastric juice, which would appear to stream continually from the inner surface of the stomach.1
" In its general composition this fluid is analogous to the saliva
" Besides Haller, consult Berlin, Mem. de VAcad. des Sc. de Paris, 1761." " Ruysch, Thes. Anat. ii. tab. v. fig. 2, 3, 4*." " See G. Fordyce, On the Digestion of Food, p. 12. 59. 191." " Walter, Tab. Nervor.. Thorac. et Abd<,m. tab. iv."
" J. H. Rahn, Mirum inter Caput et Viscera Abdominis Commercium. Get- ting. 1771. 4to.
Dit. Vegens, De Sympathia inter Ventriculum et Caput. LB. 1784. 4to. Wrisberg, Commentat. Societ. Sdentiar. Gotting. t. xvi." 1 " Ever. Home, Phil. Trans. 1817. p. 347. tab. xviii. xix."
DIGESTION. 79
equally antiseptic, very resolvent k, and capable of again dis- solving the milk which it has coagulated.1
" Digestion is performed principally by it. The food, when properly chewed and subacted by the saliva, is dissolved"1 by the gastric fluid, and converted into the pultaceous chyme ; so that most kinds of ingesta lose their specific qualities, are defended from the usual chemical changes to which they are liable, such as putridity, rancidity, &c., and acquire fresh properties prepara- tory to chylification.n
" This important function is probably assisted by various ac- cessory circumstances. Among them, some particularly mention the peristaltic motion, which, being constant and undulatory, agi- tates and subdues the pultaceous mass of food.0 The existence
k " Ed. Stevens, De Alimentorum Concoctione. Edinb. 1777. 8vo.
Laz. Spallanzani, Dissertazioni di Fisica Animate e Vegetable. Modena. 1780. 8vo. vol. i."
1 " Consult Veratti, Comment. Instituti JBononiens. torn, vi."
Seven grains of the inner coat of a calf's stomach were found by Dr. Young of Edinburgh to enable water poured upon it to coagulate 6857 times its weight of milk. Thomson's System of Chemistry, vol. iv. p. 596. ed. 6., and Fordyce On Digestion, p. 58.
m " Even the stomach itself, when deprived of vitality, has been found acted upon, and, as it were, digested, by it. See John Hunter, On the Digestion of the Stomach after Death. Phil. Trans, vol. Ixii." This occurs particularly in the splenic portion, and a complete opening is sometimes made, with pulpy ragged edges, and the neighbouring organs with which the gastric juice comes in con- tact may be also corroded. It happens chiefly to persons and brutes who have been cut off in good health soon after taking food, and is observed also in vegetable feeders and fish. Some have ignorantly doubted this, and confounded it with softening from disease. Dr. Camerer of Stuttgard, in 1818, proved the accuracy of J. Hunter's opinion, by observing this softening to occur with- out putrefaction in brutes killed in good health, and putrefaction of the body to occur without softening of the stomach ; and by ascertaining that the fluid, taken from a stomach which it had softened, produced the same change in another dead stomach to which it was transferred, but none upon another during life, though it immediately softened this stomach when the animal was killed, or both pneumogastric and trisplanchnic nerves were divided. This divi- sion alone produced no such effect. See Andral, Precis d' Anatomic Pathologique, t. ii. p. 86. sqq. A good paper, by Dr. Carswell, Professor of Morbid Anatomy in the London University, will be found in the Journal Hebdomadaire, Nos. 87. and 91., and the Edin. Med. and Surg. Journ , 1830.
" " Consult Ign. Doellinger, Grundriss der Naturkhre des menschlichen Orgn- nismus, p. 88."
0 " Consult Wepfer, Cicutee Aquatica; Historia el Noxee, in innumerable places."
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of a true peristaltic motion in the stomach during health, is, however, not quite certain ; indeed, the undulatory agitation of the stomach that occurs, appears 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.
" 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 neighbouring viscera and blood-vessels, which tem- perature was at one time supposed to be of such importance, that the word coction was synonymous with digestion."
It was once imagined that fermentation, and once that tritur- ation, 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 ferment- ation appear when digestion is perfect; and food, either defended from trituration by being swallowed in metallic spheres perforated to admit the gastric juice P, or immersed in gastric juice out of the bodyq, is readily digested.
p The Abbe Spallanzani and Dr. Stevens made such experiments upon brutes : but the latter experimented upon a man also, who was in the habit of swallowing stones and rejecting them, and who of course found no difficulty in doing the same with metallic balls.
* Experiments of this kind were made by Spallanzani, who procured the gastric juice by causing hungry animals to vomit, or by introducing a sponge into the stomach. But still more marked results were lately obtained in the case of a lad who had a fistulous opening from the stomach, in consequence of a wound through which, by means of a hollow bougie and elastic bottle, gastric juice was procured at pleasure. A portion of beef was introduced into the stomach on a thread and withdrawn for comparison, at the same time that a similar portion was plunged into a phial of gastric juice, the temperature of which was kept steadily in a sand-bath at 100°, — the degree of the stomach's temperature, ascertained by the introduction of a thermometer. The portion in the phial became completely dissolved, though more slowly than that in the stomach ; probably from the latter being supplied with a succession of fresh gastric juice, and freely exposed to it by motion ; for the action of the fluid is only on the surface, and a portion of chicken placed in a phial of gastric juice, for a similar experiment, was more quickly acted upon if agitated. The gastric juice, when first obtained, was almost as clear as water, and its antiseptic power was shown by the solutions of beef and chicken remaining a whole autumnal month without foetor or sour taste. American Me- dical Recorder, January, 1826. Spallanzani and others found, that if gastric juice is applied to putrescent matter, it removes the fcetor and suspends putrefaction.
DIGESTION. 81
" To determine the time requisite for digestion is evidently im- possible, if we consider how it must vary according to the qua- lity 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 in be- tween three and six hours after our meals."
" The pylorus s is an annular fold, consisting, not like the other rugae of the stomach, of merely the villous, but also of fibres derived from the nervous and muscular, coats. All these, united, form a conoidal opening at the termination of the stomach, pro- jecting into the duodenum, as the uterus does into the vagina, and, in a manner, embraced by it."
The digestive process does not go on equally through the whole mass of food, but takes place chiefly where this is in con- tact with the stomach, and proceeds gradually from the surface 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.1
Dr. Prout considers the solution of the food to be a common che- mical process, and to depend principally upon the combination of water with the alimentary substance by means of the gastric juice. He has shown that this part of the functions of the stomach is quite distinct, and may exist or be absent independently of the assimi- lating process. Thus, in some forms of dyspepsia, the solvent powers of the stomach are almost entirely suspended, so that the patient, though he may be able to assimilate pulpy matters, is quite unable to digest any thing solid ; while in diabetes, the solvent power of
r " Consult J. Walaeus, De motu Chyli, p. 534. LB. 1651. 8vo."
s " H. Palm. Leveling, 'Dissert, sistens Pylorum, $c. Argent. 1764. 4to. Reprinted in Sandifort's Thes. vol. iii."
1 Dr. Prout, in The Annals of Medicine and Surgery, Lond. 1817., also in Thomson's Annals of Philosophy, 1819.
Dr. Wilson Philip, An Experimental Inquiry into the Laws of the Vital Func- tions, $c. 1826. p. 121. sqq. 3d edit. Dr. Philip published subsequently to Dr. Prout's first paper. . r«
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the stomach is often inordinately increased, and every article dissolved as soon as swallowed."
Dr. Prout points out that hydrogen and oxygen essentially exist in many animal and vegetable proximate principles in the proportions which form water ; in fact, that water essentially con- stitutes a part of them. This essential water is distinct from that which is accidental and makes the substance moist or fluid. If a large portion of water enters into their composition, the compound is weaker and more easily decomposed. Thus cane sugar consists of fifty-four parts of carbon with seventy -two of water: the weak sugar of honey consists of fifty-four parts of carbon with one hundred and eight of water. We cannot at pleasure lessen or augment the quantity of this essential water, and so alter the strength of the compound. The same holds in regard to the influence of water in all organised bodies. Thus strong, fixed, and solid oils have a very small constituent portion of water, and a large proportion of olefiant gas; while alcohol, the weakest form of the oily principle, perfectly soluble in water, contains more weight of water than half the weight of the olefiant gas.
Dr. Prout contends that the first stage of digestion is the solu- tion and reduction of the proximate principles of various sub- stances, by means of water and the muriatic acid of the stomach, to their weakest condition, — to that condition in which they are the most easily decomposed and brought into new combin- ations. The effect of good cookery is to facilitate this reduc- tion of the proximate principles in the stomach to the weaker form ; x for although we cannot by art make a weak compound strong (except, indeed, by lessening the water, incidentally moist- ening or dissolving it,) we are able in some measure to make a
u Bridgewater Treatise, by Dr. Prout,
* Continental cookery is superior to ours for weak stomachs, as far as it reduces substances to a pulp ; but in the use of so much pure oil and pure sugar it is injurious, Dr. Prout remarks, to weak stomachs. For nature does not furnish sugar, starch, £c. or oil pure, but in combination. The purer we employ them, and especially those which are crystallizable, the more refractory is our food. Pure sugar, pure alcohol, and pure oil, are much less easy to be digested by the healthy stomach than substances purely amylaceous, or than that peculiar condition or mixture of alcohol existing in natural wines; or than butter. In these forms, the assimilation of the saccharine and the oleaginous principles is comparatively easy. Prout, 1. c. p. 507. sq.
DIGESTION. 83
strong compound weak. The substance of young animals con- sists generally of weaker compounds than that of old, and is therefore tenderer and easier of digestion. Besides this reduction to a weaker state, the articles of food in general are more or less dissolved in the stomach.
After the solution of the food and the reduction of its proxi- mate principles to the weaker forms, the stomach possesses the power of conversion, or of changing the proximate principles of the food into others, so that a fluid, called chyle, of pretty uniform composition, is obtained from it. Thus, it would appear, that the various substances belonging to the classes of saccharine, albu- minous, and oleaginous, are all convertible into each other, some out of the body, some only within it. The albuminous and olea- ginous require little change; and although the saccharine must require more, we ought to remember that sugar spontaneously becomes alcohol out of the body, and that alcohol is merely an oleaginous substance of a weak kind, and therefore probably un- dergoes in the stomach a similar series of changes to those which, out of the body, convert it to alcohol. y
The cardiac portion of the stomach is the chief seat of di- gestion, and when a part of the food is tolerably digested it passes along the large curvature to the pyloric portion, where the pro- cess is completed. As the cardiac half is the great digesting portion, it is this half that is found sometimes to have been dis- solved by the gastric juice after death; 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 in 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 says he found that fluids which had been drunk were chiefly contained in the cardiac portion, and, like many others, for upwards of a cen- tury and a half2, that, if the body was examined early after death, the two portions of the stomach were frequently in fact divided by a muscular contractions Dr. Haighton observed the same
y Dr. Prout, 1. c. p. 498. sqq.
z See Dr. Monro (Tertius), Outli?ies of the Anatomy of the. Human Body in its sound and diseased State, vol. ii. p. 111. 1813. a Phil. Trans. 1808.
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hour-glass contraction in a living dog, and remarked the peristaltic motion to be much more vigorous in the pyloric half.b
Van Helmont asserted that the food becomes sour by digestion, but this was afterwards denied, and acidity said never to happen except in cases of disorder. Sir Gilbert Blane, many years ago, however, declared that he had " satisfied himself that there is such an acid (the gastric) by applying the usual tests to the inner surface of the stomach of animals. This property in rumin- ating animals," he added, " is confined to the digesting stomach."6 Dr. Prout has discovered that the acid generated is the muriatic, both free and in combination with alkalies. d Tiedemann and Gmelin soon afterwards found the same thing, though without knowing, they assure us, Dr. Prout's discovery. They assert the clear ropy fluid of the stomach, or gastric juice, without food, to be nearly, or entirely, destitute of acidity, while the presence of food, or of