Manual of the physiology of man : or, A concise description of the phenomena of his organization

Front matter

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Preface

THE TRANSLATOR.

My first attempt of this kind was, to render into the English language the last labours of the immortal Bichat: I mean his "Pathological Anatomy." The favourable reception that work has received from enlightened physicians, has encouraged me again, to present myself before the medical public as a translator. I am farther led to this undertaking by a conviction, that neither the student of medicine, nor the young practitioner can better improve his leisure moments than by translating some useful work: These considerations have been the principal inducements to the accomplishment of the present translation.

This manner of becoming useful to our profession is certainly preferable to a rash and thoughtless attempt, at expressing our own crude ideas and undigested observations, by which we not only risk our reputation, but which might remain a monument of unprofitable absurdities, in spite of the most careful and polished diction.

Time only, and experience, enlightened and regu- 1*

VI PREFACE OF

lated by a just observation^ aided by a scrutinizing eye, which searches into the most hidden recesses of the mysteries of nature; and a mind endowed with a perspicuous and clear perception to record them, can alone presume, in our days, and especially in our profession, to produce an original work worthy of posterity.

But things are otherwise with respect to the translator: It is only necessary for him to possess a mastery of the two languages from and into which he translates, and at the same time to have a perfect knowledge of the subject on which he is employed.

These are the necessary qualifications; and when possessed, he may launch his bark into this "sea of troubles," though with little expectation of acquiring fame, for his tedious and irksome labours. But if, in the present attempt, I may only be useful to the students of medicine, by facilitating their arduous studies, I shall sincerely congratulate myself on the undertaking, while I indulge the hope, that it will be found by them, not entirely undeserving their approbation and careful perusal.

I have not aimed at elegance of diction, the nature of the work forbids it; and indeed, it could only be attained by a manifest sacrifice of the real meaning of the original text; but if I have not embellished my style with the flowers of rhetoric, I may unhesitatingly affirm, that I have never wilfully departed or deviated from the true meaning of my author.

THE TRANSLATOR. Vll

I may be permitted to make a single observation on the arrangement of the matter of the work itself.

M. Hutin has followed the best classification, and the clearest and simplest method of instructing in the science of Physiology. He first gives us a graphic anatomical sketch of the apparatus or organ, &c; and causes it to be immediately followed by the physiological function or mechanism of the apparatus or organ, &c. accompanied with a brief and condensed historical view, of the various opinions, facts or hypotheses, entertained or advanced, to explain the physiological functions of our organs.

In this manner, we not only possess the opinion of one author, or school, but the opinions of all countries, and men of eminence who have written on this subject; and the present work is believed, in this respect, to be the most correct summary of this science at the present time. And, in this opinion, I am confirmed by that of my friend Dr. Samuel Jackson.

PREFACE

OF THE AUTHOR.

In the circle of sciences, there is not one which does not inspire the greatest and most lively interest; but that which has man for its object — his organization — his phenomena, possesses for us something far more seducing: in effect, does there exist for a reflecting being a more powerful charm than that of being able to penetrate into himself, and there to discover the mechanism of his functions, the wonders and mystery of his life? Therefore, Physiology is, in this respect, a science which should be studied by all; — in its study, man is struck by a multitude of delightful revelations; the philosopher finds in it the foundation of a sound doctrine; every one knows how much Bossuet urged the necessity of uniting physiology to the moral sciences: finally the physician must here imbibe the first principles of his science; without it, he is exposed at every step to the danger of falling into the most disgusting and dangerous empyricism.

We have on this important subject numerous particular memoirs, and treatises ex-professo; and in mentioning only those which do honour to our age, we shall particularly name the excellent

X PREFACE OF THE AUTHOR.

works of Messrs. Richerand, Dumas, Chaussier, Magendie, Adelon, &c. In presenting to the medical student a clear, simple, and rapid abridgment of the doctrines of these great masters, far be from me the idle pretension of producing a perfect work: I only aspire to the merit of removing the difficulties which embarrass their first steps, and of facilitating and accelerating their studies, in order to pay to this body the tribute of usefulness which it imposes on each of its members. The plan which I have followed in this manual, is nearly the same as that which is adopted in the school of Paris. I give at first some general considerations which serve as a natural introduction to the study of man; then I examine in particular, and in the aggregate, the different parts which constitute the human organization; finally, I conclude by the history of the functions, or different phenomena that man presents during the course of his life.

In the particular study of each function, I recall very cursorily the general condition and structure of the organ which is its instrument; then I explain the function itself; finally, after having described its mechanism and ultimate object, I pass in review the principal theories, or hypotheses, which divide physiologists: when I differ in opinion with them, I do it less from confidence in my own judgment, than in the observation of the learned men who appear to me to approach nearest to truth, and to a knowledge of the secrets of human nature.

MANUAL

PHYSIOLOGY OF MAN.

General physiology is a natural science which treats of the phenomena belonging to organized bodies; but those bodies are innumerable, and besides they form two different kingdoms; physiology is then 1 at first divided into vegetable and animal, according as vegetables or animals are the subjects of our investigation; finally, if we study life in one single species of these two living kingdoms, then physiology receives the appellation of special. Such is in particular that of man, of which we are about to treat.

Introduction

General considerations of natural bodies.

The bodies or beings, the existence of which has been doubted by some metaphysicians, manifest their presence by a certain number of properties which produce in us an aggregation of definite sensations. The immense science which embraces them constitutes what is called natural philosophy.

In considering generally, and in a philosophical manner, the admirable variety of beings which compose the universe, we are struck with amazement on seeing that all can be reduced to a certain number of elements which, according to the present state of science, amount to fifty-six, four of which are imponderable; but these elements or material parts of bodies, mixed in different numbers, or in diverse proportions, are bound together, in their combinations, by two distinct forces; the one, the power of chemical attraction, the other, that of organic attraction, which gives to them two peculiar modes of existence, which will for a moment fix our attention.

All the bodies in nature are either inorganic or organic. Ever) 7- thing is different in these two classes of beings, not only in their material composition and power of aggregation, but also in the part they perform in the universe. The first glance < suffices to establish between them, h priori, a distinctive character, — it is life, properly so called; and is only found among the beings whose particular structure assumes the name of organization, whilst inorganic bodies enjoy only a passive existence depending upon chemical affinities and ph) T sical laws. Let us briefly examine what are the material differences which exist between these two modes of being.

1. Composition. The inorganic bodies are composed of homogeneous molecules,united by a universal power, attraction, the ordinary conditions of which are well understood, in such a manner that the chemist may at pleasure decompose and reproduce them. Some of these molecules are elementary or indecomposable, and have generally a determined geometrical form; others are the result of diverse combinations that these latter form between themselves, and are called integrant. United in different quantities, and in an order more or less irregular, these molecules constitute inorganic bodies, the volume and shape of which are very varrable.

Organized bodies, on the contrary, are composed of heterogeneous parts; some solid, constituting the organs, others fluid, which are contained in these latter. These different dissimilar parts are united by a particular power, — vital affinity, the laws of which are entirely unknown to us; so that we are unable to decompose and recompose a vegetable or an animal. We distinguish in these beings chemical and organic elements, the union of which produces bodies of a determined shape and volume.

2. Origin. Inorganic bodies are sometimes completely formed by the combination of different elements, at dthers, they are detached from a mass, or are deposited by water which holds them in solution.

On the contrary, organized bodies are always produced by Bodies similar to themselves; their reproduction occurs by a positive generation, nevertheless some moderns still admit, with the ancients, a spontaneous generation in the two organic kingdoms. (Lamarck. J

3. Growth. Inorganic bodies may at every moment considerably augment or diminish in volume; these phenomena, independent of themselves, always appertain to the general laws of matter.

Organic bodies, on the contrary, continually assimilate the nutritive particles of the bodies which surround them, and reject at the same time materials which previously formed them ; this growth, by Intussusception, constitutes nutrition properly so called.

4. End. Mineral substances can not necessarily have an end; exterior bodies are those which produce their destruction by greater affinities than those which have given them birth; the dissolution of their elements is never spontaneous.

Organized beings, on the contrary, have a determined end. Death, a name given to this end, happens with the entire cessation of the nutritive functions; the body then returns into the class of inorganic substances.

Mineralogy, chemistry, and natural philosophy, have for their object the investigation of inorganic bodies, whilst the knowledge of organization, and of the phenomena of organized bodies, belong to anatomy and general physiology; the numerous bodies which are the object of these two last sciences are divided into vegetable or inanimate beings, and animals or animated beings; the general characters that we have just pointed out in organized bodies, equally belong to both; but there exist between them some nicer distinctions, which justify us in the division of these beings into two distinct classes.

Difference between vegetables and animals.

1. Composition. We find in both classes an organization, but generally it is more simple in the vegetable than in the animal kingdom; with the former, solid particles predominate, whilst fluids prevail in the latter. In the former, one single organic element seems to exist, the cellular, whilst in the latter, three at least are distinguishable: the eel-, lular, the muscular, and nervous* tissues. Finally,

* Nevertheless, Haller, Linnaeus and M.Brachet, consider the central marrow or pith of vegetables as corresponding to the nervous system of animals; and in recent researches, M. Dutrochet not only asserts that he has found in several plants nervous ganglia, but even muscular fibres.

the chemical composition in general, is also different; oxygen, hydrogen and carbon, are the chemical elements of vegetables. In animals we remark, besides the above elements, a great quantity of azote.

2. Nutrition. Beings of both organized kingdoms draw materials from the bodies surrounding them which they elaborate and assimilate to themselves; but vegetables feed on inorganic substances; animals, on the contrary, feed almost exclusively on organic matter. The former absorb and elaborate their aliments throughout their exterior, whilst in the latter, the alimentary substances undergo in a particular organ, the digestive canal, a special change, digestion, which prepares it for assimilation. Indeed we may say that this digestion in vegetables occurs in the earth, which, according to Hippocrates, is the stomach of plants, quemadmodum terra arbor ibus it a animalibus ventriculus.

Finally, nature has given to animals only, the liberty of executing at pleasure their nutrition, whilst vegetables nourish themselves in a passive and insensible manner.

3. Sensibility. Some vegetables have the power of receiving impressions and of reacting; but none possess sensibility, properly so called, i. e. that faculty in virtue of which a being has consciousness of himself, of his existence, of pleasure and of pain. Consequently their life is necessarily spent without perception or volition.

Animals, on the contrary, which possess this faculty, are conscious of their existence, perceive and execute at will certain actions of their life, and experience sensations of pleasure and of pain.

4. Locomotion. This faculty, by which the body has the power in part, or altogether, of changing place at will, exclusively belongs to animals; whilst vegetables are fixed to the soil, germinate, grow, and die in the same spot: it is erroneously supposed by some, that certain bulbous plants have this faculty in common with animals. When they are observed for several years, it is evident that they have changed place; but let us reflect that it is no longer the same plant, it is a new bulb which grows alongside of the parent, which dies every year with the plant that it produces.

From these two faculties, proper to animals, arises a third, which is equally peculiar to them — language.

5. Generation. In animals, reproduction occurs by the voluntary union of two individuals of different sexes, whilst the greater number of vegetables are hermaphrodites, i. e. the same flower bears the two sexes; fecundation is mechanical, and is involuntarily performed. But there exists another mode of reproduction, which has the greatest analogy in the two species of organized beings; it is simple, and happens without the concurrence of two sexes. The Conferva?, the Polypi for example, cover themselves with gems or buds, in the same manner as many plants do, and which, in dropping off, give birth to new beings similar to the parents which have produced them.

In the comparative examination that we have just made between animals and vegetables, we must have remarked that these beings differ only in the degree of complication or of simplicity, and if we reflect that in order to establish differences, we have been obliged to compare the most elevated among them, it will be easy to foresee, that in descending the animal scale, nature will present a multitude of exceptions, which will always oppose a division to which she seems unwillingly to consent. In effect, there are animals in whom we have not been able to find the organs of sensibility and of motion, whilst, on the other hand, new researches seem to have fixed beyond doubt the existence of these instruments, and consequently of functions, in some plants.

Of Jlnimalsin general.

From the knowledge, which we have just acquired, we may define animals to be living organized beings, sensible, receiving consequently various sensations from the different bodies which surround them, and the greater number enjoying a free and independent existence.

Generally, animals have a symmetrical form, and may be divided into two lateral halves by a vertical line; they are provided with a nervous system expanded on the one part, throughout the whole body, and ending on the other by an enlargement; they have organs for special sensations to establish relations with the universe; they are covered with an exterior membrane, the skin, which being reflected internally, forms a cavity destined to receive the aliments. From this cavity commonly arise numerous vessels which absorb the alimentary juice and distribute it in all parts of the body; finally, most animals have respiratory organs in which this matter is exposed to the action of the air, secretory organs, where a part of this nutritive juice is eliminated from the mass; muscles to perform motions; finally, genital organs for the reproduction of the species.

2*

IS INTRODUCTION.

Such are the general characters of animal organization; but it undergoes such great modifications, from the simplest animals to those which occupy the highest grade in the scale, at the head of which stands man, that I believe it important to prepare ourselves for the study of the latter, by taking a general view of organization and the functions of the different classes of animated beings, so as to enable us to investigate naturefrom its simple to its compound form.

1. Nutrition. In the lowest animals, i\\e amorphous, the mass is homogeneous, spongy; there is no particular organ, the absorption of nutritive materials is effected throughout the whole surface of the body. Next, in the radiated animals, we distinguish the rudiments of a digestive canal; we find a simple cavity, or with radiated prolongations in every part of the animal: here the nutritive absorption occurs through two surfaces. Finally, as we ascend the scale, this cavity traverses the body, the aliment is therein received through an orifice called the mouth, and the residue is rejected by another opening, the anus.

At first, the nutritive juice is immediately carried by imbibition throughout the body, without the intervention of vessels; such is the case in the radiated animals and insects. In more elevated classes, the fluid absorbed in the intestinal canal circulates in vessels divided into arteries and veins, at the union of which is often found a heart simple or double. In the vertibrated animals, there exists besides limphatic arid chylopoetic vessels.

With the greater number of animals the nutritive fluid requires the contact of the air, in order to be proper for nutrition; and for this end there is a respiration. The radiated animals, and a few of the articulated, have no particular organ for this function, then respiration is called general; with all the other animals, on the contrary, this function is located; and according as it is executed in water or in the air, the organs are modified and assume the name of gills or lungs.

The nutritive fluid is assimilated to the organs in the same way in all the classes of the animal kingdom; it renews their substance and keeps up their temperature.

The movement of decomposition is also variable in the diverse animals, as well as that of composition. The nutritive fluid has continually secreted from its mass some of its parts, that which constitutes the secretions, the results of which differ accordingly as they are immediately rejected on the exterior, or as they return into the nutritive element. In the infusoria, polypi, acalephce, echinodermata and intestinal worms, this function is confined to a simple exhalation, of which the surface of the body is the seat. In certain arachnida, Crustacea, and mollusca, we find a liver and salivary glands; the vertebrated animals have besides two kidneys, a pancreas, &c.

2. Sensibility. All animals seem to enjoy this faculty; but they do not possess it in the same degree; the nervous system is the instrument of this function. In the infusoria, and the greater number of polypi, this system seems to be wanting. We begin to perceive the rudiments of it in the greater number of the radiated animals; we observe round their mouth small ganglia, communicating with each other by small filaments, which extend beyond and are distributed to both surfaces of the body; no central ganglion does yet appear to exist: impressions are immediately followed by motion.

The central enlargement called brain, is observed in the articulated animals. It is situated over the oesophagus; it sends all along the digestive canal two filaments, which are united opposite to each articulation, and are distributed to every part of the body. The mollusca present nearly the same arrangement; in the cephalopoda only, the central ganglion is enclosed in a kind of cartilaginous cranium.

The nervous system in these two classes is already modified in such a manner as to give birth to organs of special sensations; some have tentacula or feelers appropriated to the sense of touch, the greater number perceive odours, nevertheless, with them this faculty, as well as that of perceiving sounds, seems to depend upon a tactile impression, since no organs of these senses are as yet discovered. The gasteropoda present small black spots that are considered as the rudiments of the organ of vision: the insects, arachnida, Crustacea, the mollusca cephalopoda, &c, have simple or compound eyes, often pediculated. We see that the complexity of the nervous system in these two classes of animals continually increases; these latter evidently possess the nervous centralization in a higher degree than the preceding, hence the freedom of their movements; they have organs of the senses, hence again special sensations; finally, from these two faculties results a third which, without education, tends to the preservation of the individual and the species,— it is instinct.

Lastly, in vertebrated animals, the same filaments are no longer indistinctly sent to the organs of vegetative and animal functions. The nervous system assumes a peculiar character; it is always composed of two principal parts: 1. Of the union of numerous ganglia analogous to those we have already observed in the inferior classes, and which have under their dependance the organs of nutrition and the principal organs of reproduction; this is called the great sympathetic. 2. There exists, moreover, another nervous mass, with which communicate the preceding enlargements, and which consists, 1. In a long cord contained in the vertebral canal, called spinal marrow, whence arise all the nerves which impart voluntary locomotion to muscles. 2. In an enlargement more or less considerable, ordinarily contained in a bony case called cranium, this is the encephalon, to which all the organs of the senses tend, and which presides over the moral faculties. This organ, as we gradually rise towards man, more and more connects and binds under its dependence the whole nervous apparatus, and indeed we may even say life.

Thus in the class of vertebrated animals, besides irritability, general sensibility, voluntary movement and instinct, we also observe cerebral acts, which gradually, arise up, even to intelligence.

3. Locomotion. This faculty, possessed by animated beings, for executing partial or general movements, is gradually extended in the series of animals. Among those which occupy the inferior classes, we do not find particular organs for this function, and nevertheless the infusoria, for example, move about with an astonishing velocity; the same thing is the case with respect to the rotiferi and the polypi, which are likewise deprived of muscular organs: they begin to be appreciable in the acalephse and radiated animals. Afterwards, the apparatus of this function is more complicated, and in the same degree as the muscular system is more developed, there are added hard parts, which form the frame of the body and the levers of the limbs. In the insects, the hard parts are external, forming a part of its covering; they are composed of parts moveable on each other: the muscular fibres line their interior and communicate to them motions. In the immense class of vertebrated animals, on the contrary, these hard parts are internal, and constitute peculiar organs, the bones, about which the muscles are attached.

4. Expressions. This faculty, possessed by ani mated beings of communicating their sensations, differs very much in different animals; it is not remarked in those which are deprived of sentiments and volition. Next it develops itself, but it is only appreciable to the eye; the passions which agitate the animal are then only discovered by the different changes which occur on his surface, constituting gestures. Lastly, the superior classes have besides a peculiar instrument — the larynx; placed along the respiratory passage; it produces a kind of expression which consists in sounds; voice and speech, are modifications peculiar to man.

5. Generation. In the inferior classes there are no particular organs for reproduction; then, sometimes, as in the infusoria, the body may be divided into several fragments, which constitute as many new individuals (Jissiparous generation;) or by buds shooting on the surface of the animal, detaching themselves from the parent to produce a new being, such are polypi, (gemmiparous external generation;) or lastly, as it is observed in acalephse, it is internally that the gemmae oviform are develop-

I. 1. amo organs

2. act*1> or ^ consists in ganglia placed opposite each radia

rently distributed to both surfaces. No rudiment of radii

e stive canal, chylopoetic vessels; pulmonary or bronlood from the respiratory organs and sends it into eve- •»; generation with the concurrence of the sexes. Some Larrow situated along the digestive canal: some have nses.

3. AnTial canal complete; tracheal respiration disseminated; symrrthe muscles, the locomotive apparatus presents some it comendent upon the skin; spinal marrow under the dials are inferior to the mollusca.

nal functions; their body is composed of a trunk dividmost all have limbs; a series of hollow bones forming [ the body, and which contains the spinal marrow; he cranium, in which is contained the encephalon, ti and the organs of the senses: the mouth is comiirnished with teeth or horny matter: the intestinal cadch are commonly the salivary glands, the liver and leart, arteries, veins, lymphatic, chylopoetic vessels, Is: the sexes are separated; all the vertebrated have uscles which are inserted into them by the medium of iy all have red blood; and among the excretions, the

Accorced or not in its membranes; we subdivide the vertebrated £

Oration, till it is hatched. Birds, reptiles and fishes are

chatching: these are the ovo-viviparous. Viish. its communication with the mother; it is expelled when it I this family has a peculiar organ (the mammae,) destined toiasses all beings in intelligence.

TABLE OF THE ANIMAL KINGDOM.

1. AMOnPHOZOAIHES;

2. ACTINOZOAIHES radiated anir,

Homogeneous organization, no appearance of digestive, nervous or muscular organs. C Radiated form, digestive cavity with one or two openings; nervous system nul, or it consists in ganglia placed opposite each radia } of the animal; these ganglia have not as yet a common centre, they are indifferently distributed to both surfaces. No rue . Cmui

3. ARTIOZOAIIIES,

symmetrical form, it comprehends the

MALACOZOAIRES,

or mollusca.

ENTOMOZO AIRES.

or articulated, .subdivided into:

pparatus does yet exist; generation fissiparous or gemmiparous.

" Soft body, made out of a piece, no articulation; perfect digestive canal, chylopoetic vessels; pulmonary or bronchial respiration; double fleshy ventricle which receives the blood from the respiratory organs and sends it into every part of the body; secretory organs, liver, and salivary glands; generation with the concurrence of the sexes. Some species are hermaphrodite; they have a brain and a spinal marrow situated along the digestive canal: some have .eyes; there are even some which appear to enjoy the five senses.

"anasteozo aires f Body borne commonly on paws; intestinal canal complete; tracheal respiration disseminated; external articu- J no circulation properly so called; besides the muscles, the locomotive apparatus presents some lation or ] hard parts, but they are external and dependent upon the skin; spinal marrow under the diinvertebrated. l_gestive canal: in some respects these animals are inferior to the mollusca.

Different from the preceding by the animal functions; their body is composed of a trunk divided into two or three splanchnic cavities: almost all have limbs; a series of hollow bones forming a long shaft occupying the middle line of the body, and which contains the spinal marrow; at its extremity is the head, composed of the cranium, in which is contained the encephalon, and of the face which presents the mouth and the organs of the senses: the mouth is composed of two horizontal maxillaiy bones, furnished with teeth or horny matter: the intestinal canal is provided with secretory glands, which are commonly the salivary glands, the liver and pancreas; all have a double circulation, a heart, arteries, veins, lymphatic, chylopoetic vessels, and lungs, fishes excepted which have gills: the sexes are separated; all the verteb rated have moveable bones which form their frame, muscles which are inserted into them by the medium of tendons, and which move them; lastly, they all have red blood; and among the excretions, the .greater number have a urinary depuration. According as the foetus has acquired, or not, all its development when it is expelled, or is born, contained or not in its membranes; we subdivide the vertebrated animal into:

Oviparous. The germ is inclosed in its membranes with sufficient nutritive substances for its alimentation, till it is hatched. Birds, reptiles and fishes are

comprised in this order. Certain reptiles and some fishes keep then- eggs within, till the time of hatching: these are the ovo-viviparous. Viviparous. The egg fixed in the uterus, receives its nutrition through tire placenta, which establish its communication with the mother; it is expelled when it has attained all its development. Their animal functions are more perfect, their instinct greater; this family has a peculiar organ (the mammae,) destined to prepare the first nourishment of the new born. It is to this species that man belongs, who surpasses all beings in intelligence.

OSTEOZOAIRES,

internal articulation or vertebrated.

ed, and this constitutes internal gemmiparous generation. In higher animals, the concurrence of two organs of different sexes is needful for reproduction. These organs are mostly borne by different individuals. The only hermaphrodites are the amulati, and even then they reciprocally impregnate each other.

Classification of Animals.

Linnaeus, in considering the circulatory apparatus, established in the animal kingdom two great classes; the red and the white blooded animals; then he subdivided the first class into four orders: Quadrupeds, Birds, Reptiles, and Fishes. The second class comprehends the Insects and Worms.