FEAR

FEAR

BY

ANGELO MOSSO

TRANSLATED FROM THE FIFTH EDITION OF THE ITALIAN
BY
E. LOUGH AND F. KIESOW

AUTHORISED TRANSLATION

LONGMANS, GREEN, AND CO.

LONDON, NEW YORK, AND BOMBAY

1896

All rights reserved

TO

PROFESSOR ANGELO MOSSO

OF TURIN

from whom both have received many kindnesses of a personal character, and to whom one of us is indebted for furtherance in scientific research, we offer our sincerest thanks, with the assurance that we have looked upon the translation of this splendid little work, as the fulfilment of an agreeable duty.

E. L. and F. K.

August 1895

[CONTENTS]

ILLUSTRATIONS

FEAR

INTRODUCTION

I

Never shall I forget that evening! From behind the curtains of a glass door I peered into the large amphitheatre crowded with people. It was my first appearance as a lecturer, and most humbly did I repent having undertaken to try my powers in the same hall in which my most celebrated teachers had so often spoken. All I had to do was to communicate the results of some of my investigations into the physiology of sleep, and yet, as the hour drew nearer, stronger waxed within me the fear that I should become confused, lose myself, and finally stand gaping, speechless before my audience. My heart beat violently, its very strings seemed to tighten, and my breath came and went, as when one looks down into a yawning abyss. At last it struck eight. As I cast a last glance at my notes, I became aware, to my horror, that the chain of ideas was broken and the links lost beyond recall. Experiments performed a hundred times, long periods which I had thought myself able to repeat word for word—all seemed forgotten, swept away as though it had never been.

My anguish reached a climax. So great was my perturbation that the recollection of it is dim and shadowy. I remember seeing the usher touch the handle of the door, and that, as he opened it, I seemed to feel a puff of wind in my face; there was a singing in my ears, and then I found myself near a table in the midst of an oppressive silence, as though, after a plunge in a stormy sea, I had raised my head above water and seized hold of a rock in the centre of the vast amphitheatre.

How strange was the sound of my first words! My voice seemed to lose itself in a great wilderness, words, scarce fallen from my lips, to tremble and die away. After a few sentences jerked out almost mechanically, I perceived that I had already finished the introduction to my speech, and discovered with dismay that memory had played me false just at that point where I had thought myself most sure; but there was now no turning back, and so, in great confusion, I proceeded. The hall seemed enveloped in mist. Slowly the cloud began to lift, and here and there in the crowd I could distinguish benevolent, friendly faces, and on these I fixed my gaze, as a man struggling with the waves clings to a floating spar. I could discern, too, the attentive countenances of eager listeners, holding a hand to their ear as though unwilling to lose a single word, and nodding occasionally in token of affirmation. And lastly, I saw myself in this semicircle, alone, humbled, discouraged, dejected—like a sinner at confession. The first greatest emotional disturbance was over; but my throat was parched, my cheeks burned, my breath came in gasps, my voice was strained and trembling. The harmony of the period was often interrupted in the middle by a rapid inspiration, or painfully drawn out, as the chest was compressed to lend force to the last words of a sentence. But to my joy, in spite of all, the ideas began to unfold of their own accord, following each other in regular order along the magic thread to which I blindly clung without a backward glance, and which was to lead me out of the labyrinth. Even the trembling of the hands, which had made me shake the instruments and drawings I had from time to time to exhibit, ceased at last. A heaviness crept over my whole body, the muscles seemed to stiffen, and my knees shook.

Towards the end I felt the blood begin to circulate again. A few minutes passed of which I remember nothing save a great anxiety. My trembling voice had assumed the conclusive tone adopted at the close of a speech. I was perspiring, exhausted, my strength was failing; I glanced at the tiers of seats, and it seemed to me that they were slowly opening in front of me, like the jaws of a monster ready to devour me as soon as the last word should re-echo within its throat.

II

He who one day will write a book on the physiology of the orator will render a great service to society—to us who have to pay so dearly for 'that extravagant idolatry of ourselves’ which incites us to speak in public. But such a work must be a complete treatise, a mirror in which each might see himself and learn to what ridicule he exposes himself, what punishment awaits him, when he mounts the rostrum uncalled for and untried. Each must see himself with pallid cheeks, perturbed, distorted countenance, suffering from that unhealthy excitement which, like a storm of emotion, breaks out in trembling. Before entering the lists let each feel the oppression on the chest, the cough, the compression of the bladder, the loss of appetite, the unquenchable thirst, the dizziness which will blind him; and lastly, let each endure in advance all the innumerable gradations of pitying sympathy awakened in the audience by his own timidity.

We can better understand the influence of the emotions on the organism if we consider the long novitiate, the unwearying efforts and the countless trials of even the greatest orators before they attained to self-control, and to the simple end of preserving before the public the same intonation, gestures, and persuasive force which are natural to them when in the company of their friends or the retirement of the family circle.

I have seen men of brilliant intelligence standing rigid, their arms hanging at their sides like recruits, their features distorted and their eyes fixed on the ground, stammering and grinding out their speech, so as to move one to pity. Others, known to their intimates as jovial anecdotists, make one turn away one’s eyes in compassion when, on important occasions, they stop short in the middle of a sentence, gasp, repeat the same word four or five times, struggling for utterance, and at last stand still open-mouthed, clutching the table or their watch-chain, as though in search of an anchor of salvation. Others, again, go to a banquet and succeed in damping all gaiety. At the very beginning it is evident that food is swallowed with difficulty, their speech lies heavy on their heart, they are nervous and tortured by the fear that their memory may leave them in the lurch. One pities them when at last they rise pale and trembling, then speak confusedly, jerkily, swaying to and fro with wide-open eyes, as though stupefied with agitation.

A former master of mine, once professor of sacred rhetoric at the Athenæum of Turin, could, at the beginning of a nervous affection, only speak sitting, owing to the excessive trembling of his legs; and at last he was obliged to renounce the triumphs which his masterly and enviable gift of eloquence procured him, as he was unable, after having concluded his speech, either to rise, to descend from the cathedra, or to walk.

But why does the simple fact that we are standing before the public produce such disquietude within us? Why is it followed by such a far-reaching disturbance of the organic functions? We say it is the nerves, the brain, anxiety, the physical nature of man which we cannot control. But there is confusion also in our ideas. What is this much-praised force of will, this power of the soul which makes us so bold when alone and yet so cowardly before the eyes of a few people?

I confess the problem is difficult, and I believe the easiest way to a partial solution is to analyse without prejudice what we all know about cerebral activity, and to see what physiologists have discovered in studying the emotions and the physical phenomena of thought.

III

Before, however, entering the field of experimental physiology, I allow myself the following remarks. In strict justice the names of many physiologists should be repeatedly mentioned, but I prefer to do so only from time to time, as I fear the interruption of the sentence by names and notes might be tiresome to those whose eye is unaccustomed to the perusal of scientific books, nor do I think there are many who would be curious to know the paternity of every assertion I shall make use of. In order, however, that no undeserved merit may be ascribed to me, I shall, without further ceremony, write in the first person only when an experience or an idea of my own is to be communicated, so that, if I shall be at fault, science may not be held responsible for a personal error.

The first really important book on the physiology of the passions was written by Descartes, the great restorer of science, who, with his prodigious force of intellect, embraced all branches of knowledge, and was at once mathematician, physicist, and physiologist. His is the honour of having shown that the old Aristotelian philosophy, then prevalent in the schools, had never solved one of the problems respecting life. In the treatise upon 'The Passions of the Soul,’ the following words appear in a section in which he investigates the manner in which the passions are excited: 'If the appearance of an animal is very strange and frightful—that is, if it has much resemblance with those things which were originally hurtful to the body, it will excite in the mind the passion of fear, then of boldness or of horror, according to the different temperaments of the body or the force of the soul, and according as one has been able or not to provide one’s self with the means of defence, or of flight from those dangerous things with which the present impression has points of resemblance. This in some men disposes the brain in such a manner that the spirits, excited by the image and formed in the pineal gland (or central part of the brain), pass thence, partly to the nerves which serve to turn the body and move the legs in flight, and partly to those nerves which enlarge and contract the valves of the heart, or stimulate the other parts, whence the blood is sent to them in such a manner that this blood, otherwise elaborated, sends spirits to the brain capable of fomenting and increasing the passion of fear; that is, they are able to keep open or reopen the pores of the brain which conduct them to the nerves.’[1]

No one before Descartes had had so simple a conception of the mechanism by which the involuntary movements accompanying the emotions are produced, and he it is who laid the foundations of the physiological study of the mind. Two centuries and a half have already passed, and his work still remains a monument worthy of all admiration. Science has advanced so greatly that perhaps no one now who wished to learn the elements of physiology would study his treatise on man, and yet none who know the history of science but are moved by those marvellous pages out of which breathes that spirit of innovation which has fertilised the science of centuries. Malebranche relates that when he first took up the treatise—'L’homme et la formation du fœtus,’ by Descartes—the new ideas it stirred up within him gave him a pleasure so intense, and so filled him with admiration, that his heart palpitated and he was obliged to pause from time to time.

Other two no less celebrated names must also be mentioned here, on account of the strictly scientific character they have given to the study of the emotions. These are Herbert Spencer and Charles Darwin. Next to these stands Paolo Mantegazza, with his celebrated researches on pain and his book on physiognomy and mimicry, dedicated to 'Charles Darwin, who, by his immortal work on the expression of the emotions, opened up a limitless horizon to the science of the future.’ The homage of the illustrious Italian physiologist is worthy of the great English master and philosopher. Darwin was a man of genius and at the same time one of the greatest masters of the popular style of authorship. His force lies in the caution with which he made statements and drew conclusions, thus avoiding all absolute formulæ, and this will always make him an incomparable model. Dogmatism, that worm which gnaws and sterilises mediocre minds, which corrupts the rationality of the many—dogmatism, that plague of science, had no hold on him, Darwin knew it not. He candidly shows the public the gaps in science, criticises himself unmercifully, and does not hesitate to point out the defects in doctrines he himself propounded. In reading his books one is inclined to think that he was continually haunted by the fear of being misunderstood by readers insufficiently educated for the comprehension of deeper scientific questions. He was so careful, so temperate in his assertions, so cautious in his inductions, that in his book, 'The Expression of the Emotions,’ which, in my opinion, is one of the less excellent of his works, he leaves not one point on which one can conscientiously contradict him, by taxing him with an error.

And if we are able now to add to his discoveries and to correct some of the judgments in his works, it is only thus because science marches onward with such giant strides that we, although we were his contemporaries, belong even now to a later age, as the context of this work will more clearly show. The theory of evolution will always remain the foundation-stone of modern science, but certain principles formulated by Spencer and Darwin will be modified as our knowledge of the adaptation of organs to their functions increases.

IV

Darwin attributed, I think, too much importance to the will considered as the cause of expression. We younger physiologists are more mechanical; we examine the organism more minutely, and it is in the structure of the organs that we seek the reasons of their functions.

I shall here give an example of this different way in which I have explained a few phenomena.

Rabbits are, as is well known, extremely timid animals, and it is remarkable that no other blushes and grows pale so easily as the rabbit. The changes in circulation produced by psychical impressions and by the emotions are more observable in the ears than in the face, as is indeed the case with many men. In Northern Italy, after someone has received a vigorous scolding, I have heard the popular expression used: 'He caught it hot enough to make his ears turn red.’ In the middle of the auricle of the rabbit’s ear there is an artery, running from the base to the summit, which ramifies and winds in such a manner as to form two veins on the edge of the auricle. In 1854, Moritz Schiff observed that this artery showed alternate movements of contraction and expansion, not corresponding to the systole and diastole of the heart. If one looks at the rabbit’s ear against the light, from time to time one sees the artery decrease in diameter, until at last it quite disappears, then it increases again, and, as it swells, it expands all its branches, so that the whole ear becomes of a vivid red and also warmer. This fulness of blood in the ear lasts a few seconds, then artery and branches contract and the redness gradually dies away. Schiff called this artery an accessory heart, because he imagined that the contractions and expansions observed by him in the vessels of the ear were to promote a better circulation of blood in the ear of the rabbit, just as the heart does for the rest of the body.

In repeating Schiff’s observations I used certain precautions which others would perhaps have thought superfluous. Instead of watching the rabbit while holding it in my hands, I thought to spare it all emotion, by enabling myself to observe the ears without its becoming aware of the fact. For this purpose I had a cage made in such a manner that it fitted exactly into the inside frame of a window, and whereas it was impossible for the rabbits to look into the room, I could watch quite easily, without being seen, through a few holes in the cage. By means of this simple arrangement I could observe the rabbits at my leisure, and study their habits while they were quiet, without a suspicion that they were being noticed. The first time that I so watched them, I saw, to my surprise, that the ears were no longer so red as when the animals were startled by feeling themselves seized and held fast in my hands on the table. The rapid movements of dilatation and contraction in the blood-vessels of the ear, the sudden blushing and loss of colour so characteristic of the timidity of these animals, were no longer observable. The artery of the ear remained dilated and of a vivid red for a long time, often for hours. I noticed this especially in summer, when the animals were uniformly tranquil. A state of absolute repose, however, is not always accompanied by an expansion of the blood-vessels. All rabbits have not ears equally red or pale at the same time and under the same conditions. A similar circumstance may be noticed at any time in the faces of men. Young rabbits blush more easily than old ones. Often while watching the buck and doe with the young ones, one could see the ruddy ears of the latter turn pale every now and then, while the former, like old people with us, remained calm and had pale ears. But even amongst the young ones of the same litter, one finds considerable differences in the facility for blushing.

At the market I chose those animals that blushed most easily and frequently, just as the slave-dealer picks out for the harem those women who charm by blushing more vividly than the others. If one studies attentively the loss of colour in the ears of a rabbit when perfectly quiet, one can nearly always discover the cause in some external circumstance. Often while the animal has red ears and is breathing quietly, one notices a sudden change in the rhythm of respiration; the rabbit lifts its head, looks around, or sniffs; a contraction of the blood-vessels follows, and the ears become pale. After a few minutes, if nothing happens, the ear becomes red again. Any noise causes renewed pallor. A whistle, a cry, a sound of any kind, the bark of a dog, a sunbeam suddenly penetrating into the cage, the shadow of a swiftly passing cloud, the flight of a distant bird, each suffices to produce a rapid loss of colour in the ears, shortly followed by a more vivid flush. We may therefore maintain that the circulation of blood in the ears reflects the psychic condition of the animal, and that nothing takes place either in itself or in its surroundings without immediately acting upon these blood-vessels.

Thus the fact observed by Schiff receives confirmation, but the explanation which I give of it differs from his. The dilatation and contraction of the arteries in the rabbit’s ear can no longer be compared to the movements of an accessory heart, and, in my opinion, correspond to the colour or pallor of the human face. In this manner the phenomenon is deprived of the exceptional character with which it was introduced into science, and takes its place amongst those observable in man and nearly all animals.

We may see the same phenomenon noticeable in the rabbit’s ear, in the cock’s comb and wittles; during emotion the fleshy protuberances and the skin on the neck of the turkey distinctly blush and grow pale, and in men and dogs not only the face but also the feet are subject to these changes of colour.

These things were unknown owing to insufficient observation. It was thought that animals did not blush, because the blood-vessels of their skin lie concealed under hair, feathers, or scales, and because the epidermis is less transparent and the pigment cells more abundant in the lower layers of the skin. And so blushing was deemed a privilege of man, which, however, is not the case. It suffices to study the face of the rabbit attentively in order to see that it is very sensitive, even to the slightest impressions. If one looks carefully at the nostrils and lips, considerable variations in the colour may be observed, corresponding to those occurring at the same time in the blood-vessels of the ear. These phenomena became so familiar to me during my study of rabbits, that I needed only observe the muzzle of the animal, and more particularly the tip, in order to know at once whether the ears were at that moment pale or red. This certainty was in part due to the alteration in the rhythm of breathing and in the movement of the nostrils produced by the slightest emotion, as also in man.

V

Many may regret that such a characteristic difference between man and the other animals should be effaced, and that we should try in cold blood to prove that what is most noble, beautiful, and human in our countenance, we have in common with the brutes. But we console ourselves with the reflection that poetry, enthusiasm, inspiration and passion rise again under new and stronger forms in the contemplation of reality, that in the search after truth there lies a fascination which beautifies and ennobles the human intelligence, and that sentiment is never extinguished by any advance of science.

To-day, when the experimental method is spreading so rapidly, it behoves us physiologists to be humble and to ask for hospitality in the studio of the artist, in the libraries of men of letters, in the drawing-rooms of cultured people, in order to diffuse the elementary principles of our science. The time has come when we must throw off our professorial robes, tie on our aprons, roll up our sleeves, and begin the vivisection of the human heart according to scientific methods.

Let the artist no longer confine himself to a blind imitation of nature, to a perpetual reproduction on canvas, in marble, or in books of the phenomena and forms of life; he must know the why and wherefore of things, completely or in part, the connection between cause and effect; he must convince himself that nothing is the result of chance and that there is a reason behind every phenomenon. Blushing—that ideal token of innocence and purity—is no accidental fact; it was not given to man as a sign of nobility, nor as a mirror to reflect the agitation of his heart; it is a fact rendered necessary by bodily functions and which the will can neither produce nor suppress. It is simply caused by the structure of our vital machine, by the activity of the blood-vessels in all organs and in all animals.

Darwin believed, on the contrary, that it was a phenomenon produced by means of the will. I consider it advisable to quote here in full the explanation which he gives of blushing, as no other naturalist made it the object of such special study, and because his hypothesis is at variance with the facts of my observation.

'Men and women, and especially the young, have always valued, in a high degree, their personal appearance, and have likewise regarded the appearance of others. The face has been the chief object of attention, though, when man aboriginally went naked, the whole surface of his body would have been attended to. Our self-attention is excited almost exclusively by the opinion of others, for no person living in absolute solitude would care about his appearance. Everyone feels blame more acutely than praise. Now, whenever we know, or suppose, that others are depreciating our personal appearance, our attention is strongly drawn toward ourselves, more especially to our faces. The probable effect of this will be, as has just been explained, to excite into activity that part of the sensorium which receives the sensory nerves of the face; and this will react through the vaso-motor system on the facial capillaries. By frequent reiteration during numberless generations, the process will have become so habitual, in association with the belief that others are thinking of us, that even a suspicion of their depreciation suffices to relax the capillaries, without any conscious thought about our faces. With some sensitive persons it is enough even to notice their dress to produce the same effect. Through the force, also, of association and inheritance our capillaries are relaxed, whenever we know, or imagine, that anyone is blaming, though in silence, our actions, thoughts, or character; and, again, when we are highly praised.’

'On this hypothesis we can understand how it is that the face blushes more than any other part of the body.’ 'Of all expressions, blushing seems to be the most strictly human.’ 'But it does not seem possible that any animal, until its mental powers had been developed to an equal or nearly equal degree with those of man, would have closely considered and been sensitive about its own personal appearance. Therefore we may conclude that blushing originated at a very late period in the long line of our descent.’[2]

I hold that this explanation of blushing is no longer tenable, and I think that perhaps Darwin himself would have accepted mine, since it seems to me truer, more in correspondence with the theory of evolution, more Darwinian, if I may be allowed the expression.

But why do we blush? some will ask, who insist on penetrating to the root of things. Why, under certain conditions, does the blood flow more abundantly into the rabbit’s ear and the human face? The answer to this question will be better understood when I have shown that the brain also becomes redder after an emotion. For the maintenance of life it is necessary that a dilatation of the blood-vessels should take place in all those organs in which a disturbance occurs. We all know that when our hand has been firmly squeezed, or when we have received a blow or contusion, the skin reddens at once. This change in the circulation is indispensable, for the more copious flow of blood to that part which has suffered an arrest of nutrition serves to renew the vital processes and to repair the damage caused by the injury. The same phenomena appear in the brain under psychic conditions. Emotion occasions greater energy in the chemical processes of the brain; there is a modification in the nutrition of the cells, the nervous force is more rapidly consumed, and therefore the expansion of the blood-vessels of head and brain tend, by a more abundant supply of blood, to preserve the activity of the nerve-centres.

It is in the tissues, in the properties of the living substances which constitute the vital machine, that we must seek the reasons of numerous phenomena which Darwin deduced from external causes, natural selection or environment. We shall endeavour to confine within much narrower limits the effects of chance, will, and accident, which play such an important part in Darwin’s theory. Nothing is the result of a creative force serving a premeditated end; organisms have formed and changed themselves through causes exclusively mechanical. Work perfects organisms, and the operative parts undergo, through their own activity, far-reaching modifications, which render their structure still more perfect.

CHAPTER I

HOW THE BRAIN WORKS

I

Before beginning the study of the nerve-centres I shall remind the reader of a few very simple facts, which, doubtless, he already knows, but which, recalled, will render more apparent the part taken by the body in the functions of the mind.

In order to know how the brain works, it is sufficient to recall the pictures and visions which pass before us when we are absent-minded. How curious it is when the mind sets out on its fanciful wanderings! when, unconsciously, we leave the everyday world behind us and stand motionless, with open eyes, seeing and hearing nothing.

How often in the quiet of our study, while reading a book, have we not seen the words gradually fade one into another, until we found ourselves as though enveloped in a cloud, far away amid the recollections of childhood or the hopes of the future! And what wonderful forms grow out of the flames, the logs, and the sparks glowing under the ashes, when we draw close to the fire in lonely evenings!

It is an actual relief to many, this repose of attention, this extinction of the will which steals over us in the midst of life’s troubles, lifting the burden of care and allowing us to contemplate quietly the curious spectacle which, when left to itself, the brain at work presents. How rapidly things and thoughts are transformed, melting into each other without order, aim, or pause! How easily we glide by winding paths through time and space, while in endless succession new horizons and new countries rise before us! What airy phantoms look down from the clouds above, what voices and harmonies strike the ear in the waterfalls of the brooks, what living pictures peer at us from amongst the flowers and grasses on the bank! Then suddenly a flood of memories rushes over us and leaves us confused, bewildered, as it rolls on again to the dim horizon of consciousness. And in this rushing flood of thoughts and forms we see the familiar faces of those whom the grave seems to give back to us, and we hasten to meet them with smiling lips or with tears in our eyes.

II

And yet these are nought but dreams of the waking mind. Even when the force of attention and the energy of thought are greater, we still are carried away by the wilful, untamable current of cerebral activity; because the will can do nothing within the domain of the imagination, and because the brain is no slave who will obey our very nod. Who does not remember the painful and useless endeavours made to rid oneself of an annoying thought and that incapacity for mental work which afflicts us, without our knowing whence it came? How often have we sat for hours at the desk, with idle pen, our head in our hands, unable to wrest even one thought from the mind which we dared transmit to paper! How depressed we are on those days when the sources of the mind seem dried up, when we torture ourselves in vain, ransacking our brains and finding nothing but fragments, crumbs of thought which we reject angrily as worthless refuse!

We must resign ourselves. We feel ourselves humbled as though the door of our own house had been shut in our face. It is of no use to be sad and annoyed; even if we give way to furious passion, it does not help us. We stand behind a high wall which we cannot break down. An English physiologist compared the thinking man to a simple engine-driver. He does not move the trains, neither does he determine their departure or their stoppage, he merely guides their movement, directing them first in one direction then in another.

The brain is perpetually at work, and it is impossible for the mind to embrace its activities in every part. The greater the attention is in one part, the more vague is the knowledge which we have of contiguous parts, the less vivid are the impressions which the senses transmit from the outside world. We need only recall the well-known example of Archimedes who was killed by a Roman soldier during the siege of Syracuse, while he stood in calm contemplation of some geometrical figures.

The whole of our brain is never at work at one time; now it is the one half, then the other which is in action.

When looking at the sky or at a wall in a uniform light with only one eye, I found that the field of vision changed alternately from light to dark. This does not depend upon the eye but upon the brain, because unconsciously we use first one eye then the other; and, in the same way, the two hemispheres of the brain do not work simultaneously, sometimes it is the one sometimes the other which is in a state of activity. A French general had lost one half of his brain from a wound which clove the skull. He recovered and retained his intelligence and gaiety, but he used soon to grow tired during conversation and could only continue any intense mental work for a few minutes at a time.

There are many philosophers who maintain that a considerable portion of our cerebral activity is purely automatic, so that our mind is often in operation without our being conscious of it. When an idea, says Maudsley,[3] disappears from the horizon of consciousness, it need not vanish totally, but may remain, as it were, latent or veiled, continuing by its movements to awaken, to give rise to, other ideas without our being aware of this activity. But when our consciousness is unexpectedly drawn off from its work, or roused by something which had before occupied it, then we catch the idea at work.

This opinion is rendered probable by a few phenomena which I observed during my studies of the circulation of the blood in the brain, and we may easily convince ourselves also, if we reflect, how often, quite unexpectedly, names and events occur to us when we were least thinking of them, and which we were unable to recall for a long time and in spite of wearisome efforts, when we wished to do so. And we all know that we are unable to fall asleep at will, so little mastery have we over our thoughts. We direct our minds first to this object then to that, in order to draw it away from that which occupies it and keeps us awake. We try to suppress an idea which torments us by calling other ideas to our assistance in ousting it, and often wait powerless for the coming of that silent oblivion and calm of mind which alone can give us rest.

If, in the moments preceding sleep, when the mind is comparatively quiet, we make an effort to fix our thoughts on something, we notice how they vacillate, disappearing and reappearing, as though we were in a boat and our heads were lifted from time to time above the waves. Even when awake we find ourselves only too often in this humble bark in which every puff of wind drives us far from the shore we wish to reach, when impetuous currents of thought prevent our entering the haven, or when the waves open to plunge us into unfathomable depths out of which we can see no horizon.

III

But in order better to see the link which binds the substance of our organism to the activity of thought, the correlation between the nutrition of the body and the mental state, or, as one is accustomed to say, the relation between body and soul, let us carefully notice what takes place when a number of friends are assembled at table.

After a few cheerful remarks made by the most jovial as they take their places, a certain gloom spreads over the company. One might almost think only a few were sociably inclined. Someone attempts to break the ice, but it is a failure; one feels that the conversation is forced, jerky, altogether wanting in sparkle. Little by little the guests brighten up. A hum ensues, then a confused buzz, like the tuning of the instruments of an orchestra, which rapidly increases in pitch, as though each were trying to make his voice heard above his neighbour’s. It seems as though something in their brains had been loosened and the vocal cords had gradually got into working order. At dessert even the more taciturn, if they have done full justice to the banquet, pour forth an unceasing stream of conversation. Moody faces become smiling, and melancholy gives place to gaiety. The cross-fire of talk, the hot discussions, the frequent bursts of laughter, the lively play of feature, the witty interruptions, the excited gesticulations, all show a hundredfold increase of vital action.

And from the glowing faces, the sparkling eyes, we know that the blood is rushing in abundance to the brain. The tongue is loosed, ideas accumulate in the mind, as though some kind hand had set the rusty wheels of thought in motion and poured oil on the hinges of the vocal mechanism.

There is no need to say more. We have all experienced this transformation which takes place in the work of the brain. It enters on another phase when the wine begins to circulate. If we had not already met the guests on similar social occasions, we should be greatly surprised at their metamorphosis, and feel constrained to correct previous misconceptions of their character. Men, whom I had always thought silent and cold, I have seen, to my amazement, carrying on the most daring discussions with brilliant fluency, and rebutting sarcasms with such promptitude and success as to earn them loud applause. Other timid ones, known to all as slow, tiresome, clumsy talkers, find in the wine-glass a sparkling vivacity, a flow of speech which makes them more agreeable; nor do they hesitate to propose toasts and drink to the health of each of the guests. They rise, glass in hand, finding a witty word for each and showering compliments on all sides. Men, calm and sedate, in whom none suspected a poetic soul, are capable of rising and improvising verses, and we are full of admiration at their skill, and at the harmonious grace of rhythm, metaphor, and rhyme.

Each one feels something like inspiration within him, as though warmed by the quickening pulse of life.

But let us leave the joyous company: so far as our psychological study is concerned, we have already lingered too long, and it would be superfluous to follow them as they leave, in order to see how confident, kind, and courageous they have all become.

The next day each will resume his own character and his own business. If it happens that one of the guests meets another in the street, they smile as they shake hands, and words which are a revelation are heard: 'We were a lively party last night, eh? I scarcely recognised you, and as for some others, there was no keeping them quiet!'

IV

The analysis of memory better than anything else shows us the connection between the various parts of the brain which enter into activity in order to provide us with the elements that form speech.

We must distinguish two kinds of memory:

1. The fixation of impressions, whether these be images, or representations of movements, words, sounds or sensations.

2. The re-awakening of these impressions as recollection.

The phenomena of memory remain quite incomprehensible if we do not admit their intimate connection with physical changes of the nerve substance. An external impression acting upon receptive nerve-cells is retained by them permanently, as though it were photographed, if it be allowable to explain the unknown by a comparison with the known. It is the blood which carries those substances to the brain which are necessary to the functions of memory. Attention cannot be developed in all its intensity without causing considerable alterations in the circulation. Now when we are absent-minded, images leave no lasting impression on the memory, as no provision is then made by the physical changes in the organism accompanying attention for a more rapid circulation of blood in the cerebral hemispheres.

The old notion that the brain was a storehouse in which each idea had its nook where it might stay till needed, is truer than it appears. Modern science has proved that the matter is much more complicated than one thinks. It suffices that the blood should coagulate in the artery which carries it to some convolution, or that a tumour should destroy a part of the brain, for us to lose, as it were, a province of memory.

Let us first consider verbal memory. That region of the brain in which it is placed is, generally speaking, the parietal region of the left side; so that anyone who has had a blow on the temple at that side nearly always loses his speech, although he still remembers things and can pronounce their names when they are repeated to him by others, a sufficient proof that the movements of the tongue are not impeded. Sometimes it happens that a person in this condition looks in the dictionary for the missing word, in order to recover the pronunciation of it.

In learning a language, we believe that certain cells undertake functions which they did not before possess, that connections with other cells are established, like very intricate nets in which the impressions of nouns and verbs, the graphic representations of ideas and words, are collected. As we exercise ourselves in the language, the blood carries new elements to these cells, and the greater our attention, the stronger become the impressions. Oxidation does not destroy the impression once received, but it weakens it. If we have had no practice for some years in speaking a language, we meet with great difficulties, our communications being made in set, stiff words; but after a few days one regains the former fluency.

We might quote cases in which, through illness, a man has completely forgotten a language, recovering it as health returned. Others have forgotten several languages in the order of succession in which they had learnt them, regaining them later in the inverse order to that of acquisition.

When groping in the dim recesses of memory, we always perceive that there are associations and intimate connections amongst the phenomena of thought. The blood, making its way into certain parts of the brain, is like the light of a torch penetrating subterranean passages, on the walls of which are painted pictures of things we know. Often the blood-vessels do not yield, and we then wander in vain in that labyrinth, retracing our steps, roaming hither and thither, until suddenly we see an opening, and what we were seeking appears unexpectedly before us. The supposition that we here have to do with an effect of the blood, an expansion or contraction of the vessels, and with phenomena of nutrition, seems to be strengthened by the circumstance that sometimes, in consequence of violent emotion, a succession of things which before seemed totally forgotten suddenly reappears in our memory.

The link between physical phenomena and phenomena of memory is more apparent during fatigue and the refreshing state of repose. Memory may fail entirely from anæmia, from poisoning by narcotics, innutrition of the brain, and in old age; for we all know how much better we remember the events of our youth than those of later occurrence.

Men who have had wounds or contusions on the head have been known to forget that they had children; authors have forgotten even the titles of their works; but as soon as the fever had passed, or the wound healed, they regained their memory. Others, during a fever, have related events and remembered names which they had quite forgotten previously, and which they were unable to recall after recovery.

CHAPTER II

REFLEX ACTION AND THE FUNCTIONS OF THE SPINAL CORD

I

Until 1820 physiologists believed that all nerves had the same functions; that is, that all were sensory.

We can scarcely picture the confusion in the mind of anyone studying the nerves of the face when, besides those destined to the organs of smell, sight, and hearing, he would notice two other large nerves—the Trigeminus and Facialis—passing off separately from the brain and spinal marrow, and which, with a double ramification of filaments, cover all superficial and underlying parts of the face; and again, when he saw the three nerves of various origin which go to the tongue, the four which are distributed in the throat, and finally, in the midst of this net of nerves, thick bundles of fine filaments and ganglia of which the origin was untraceable.

It was an English physiologist, Charles Bell, who solved this problem by showing that the most important nerves of the face, with the exception of the special sensory nerves, are confined to two. If one of these nerves, called the trigeminal, be cut through, every trace of sensibility immediately disappears from the corresponding side of the face; if the other, the facial nerve, be severed, sensibility remains, but the face completely loses the power of movement, there is no longer any contraction of the muscles or change of expression in the face.

I quote Charles Bell’s own words, since these two simple experiments still form the base of the physiology of the nervous system.

'If we cut the division of the fifth nerve which goes to the lips of an ass, we deprive the lips of sensibility; so when the animal presses the lips to the ground, and against the oats lying there, it does not feel them, and consequently there is no effort made to gather them. If, on the other hand, we cut the seventh nerve where it goes to the lips, the animal feels the oats, but it can make no effort to gather them, the power of muscular motion being cut off by the division of the nerve.’[4]

The same takes place in the hand, the legs, and in all other parts of the body, which, according as the one or the other set of nerves is injured, feel but cannot move, or move and do not feel.

In the ordinary circumstances of life no one becomes aware of these two fundamental properties of the nervous system, or at least we do not reflect that there are two distinct apparatus: the nerves which make us feel, and the nerves which cause movement. The intimate connection between these in the nerve centres and at the surface of the body renders special methods necessary to separate them, and allow them to act independently of each other.

Claude Bernard, the greatest of French physiologists, and one of the most agreeable and successful authors who have ever popularised science, showed how these two elements may be dissociated by introducing certain poisons into the blood, which kill the finest ramifications of the nerves in the most inaccessible parts of the organism.

If one scratches the skin of a dog with a poisoned arrow, like those used in war by certain savage tribes of America, the animal succumbs in less than a quarter of an hour. This terrible poison, called curari, destroys the motor nerves, but produces no change in the intelligence, and the functions of the sensory nerves. The dog scarcely notices the slight puncture on the skin and continues to walk about the room; but in a short time the hind-legs become stiff, one can see that they no longer obey the will; the posterior part of the body sways and falls. The animal rises and stumbles; then the fore-legs fail and the dog stands still. If we call him, or pat him, he responds with movements of the head, the ears, the eyes, and by wagging his tail. Soon however he cannot lift his head and lies stretched out, breathing quietly, as though reposing at his ease. On being called, he moves his eyes and feebly wags his tail, without any manifestation of pain. At last the respiratory muscles cease to act and life ebbs out without a single convulsive movement, and for a few moments sensibility and intelligence are still distinguishable in the fixed and glassy eye. It is like a corpse that perceives and understands everything going on around it, without being able to move, retaining sentiment and will but having no means of manifesting them.

II

In an investigation which I made with Professor E. Guareschi[5] into the effect of cadaveric venom, we found that all substances which slowly destroy the organism must produce phenomena analogous to those of curari, since the motor nerves, according to our researches, have less vitality than the sensory.

In order to be convinced of this fact, it suffices to take a rabbit and stop the circulation in its hind-legs. Placed on the ground, after a few seconds the animal cannot move its hind-legs, but if one presses them it squeaks and tries to escape with the aid of its fore-legs, dragging after it the hinder part of its body, which remains paralysed for a few moments. A sudden anæmia can therefore destroy motility but leave sensibility uninjured.

When life is slowly ebbing, when the circulation gradually slackens and the death-agony is prolonged, I believe that there is always a point of time in which, with the exception of the respiratory and cardiac muscles, all others are already paralysed, in which all is dead but the sensory nerves.

The hand, which with a last effort has been laid in blessing on our head, has sunk back on the coverlet never to be raised again, never to move the fingers which still feel the pressure of the farewell clasp; but the fixed eye still sees the shadows of the loved ones bending down to press tearful kisses on the brow, and when the last breath has fled, the mother still hears the despairing cry of her children and can no longer respond even by a look.

III

We have therefore two sorts of nerves: of sensibility and of movement. Let us now try to form a correct notion of an involuntary or reflex movement, which I shall illustrate by the following example.

Let us imagine a large house of which the entrance is at some distance from the street door. A bell is fixed inside, the wire of which, after passing through various holes, terminates in a handle near the outer door. When some one comes and pulls the handle the bell rings, and the maid opens the door by pulling at the cord inside the house. This series of actions represents what physiologists call a reflex movement. The maid is a nerve-centre, the bell-wire a sensory nerve, and the cord which opens the door a motor nerve. In the organism we see muscles or glands instead of the door, but the mechanism is similar. Just as the door-bell rings a hundred times a day on all imaginable occasions without our needing to open the door, and without the maid coming first to our study to ask what she must do; so we have in our nervous system two distinct parts: the maid, represented by the spinal cord, and the master, by the brain.

Let us now see what happens when the master is not at home, or what an animal does when its head is cut off, and only the spinal cord is left. We shall see here, too, that the more liberty the master gives to the maid, the more arrogant she grows, at last lording it over the master himself.

A decapitated frog does not die immediately; it may move for days, and if deprived of the brain only remains alive for some time.

We will consider the more usual case, namely, that of a frog of which the head has been completely cut off with a pair of scissors. The animal shivers and writhes for a few moments, then it stops, and would remain motionless if it were kept under a glass cover in a damp atmosphere, where nothing would irritate the skin. But if we touch its leg or put a drop of vinegar upon it, the animal tries at once to escape and to remove the disturbing agent from the surface of its body. If we put a drop of vinegar on the left leg it tries to wipe it off with the right, and vice versa. But if we cut off one of the legs or bind it fast, and then put a drop of vinegar on the other leg which is at liberty, the frog makes use of this same leg to rub away the drop.

At first sight this seems to be an act of intelligence. It may be maintained that it is done by choice, but we cannot say that this activity requires the guidance of the intelligence. A dog of which the spinal cord has been severed and a sleeping man make the same movements.

Neither must it be thought that these movements are only to be found in frogs and the lower animals. We shall see that in man also they perform all the most indispensable vital functions without the co-operation of the brain. Fontana, one of the most celebrated Italian physiologists, discovered, as early as the middle of the last century, that one could decapitate rabbits and guinea-pigs without causing their immediate death. And he also found that if care were taken by previously binding the most important arteries; so that the animal should not lose too much blood, and if the respiration were sustained artificially by means of bellows, it could live for some time, and show itself sensitive to external stimuli.[6]

IV

If we could hear the soliloquies of the man who is writing a book, many, I think, would renounce for ever the pleasure of setting the printing press in motion. It would be a curious experience, if one could read between the lines the tale of discouragement, uncertainty, trouble, and know the repeated struggles by which some difficulty was overcome, a passage was composed, a clause or a sentence written. In scientific works it would be seen that the most frequent interruptions and exclamations arise always from doubt, and the anxiety which torments an author of not making his meaning clear.

There is no remedy. He who wishes to explain a scientific subject in a clear and simple way must stop from time to time; he must come out of himself and take his reader’s place, forget all he knows in order to listen impartially to his own voice, and to judge if what he has said may be easily understood. And this I shall do, but the reader must not be repulsed by the first difficulties: our first steps cost the greatest effort. In order to comprehend the physical nature of man, and to know how this exquisite machinery of ours works, we must first examine attentively some of the most important organs which are constantly at work in our nervous system. It is in science as in the study of languages, one must first learn the meaning of the most indispensable words in order to understand what is said to us in the foreign tongue.

Till the beginning of this century very confused notions prevailed as to the activity of the brain and spinal cord. Luigi Rolando, the celebrated physiologist of the University of Turin, was the first who clearly showed that the medulla oblongata (that part of the spinal cord which lies nearest the brain) must be regarded as the centre of the whole nervous system. No one in his time knew the structure of the nerve-centres better than he, and it was he who proved that the medulla oblongata 'is the first rudiment of the nervous system, the seat of physical sensibility, of instinct, the director of voluntary movements, the centre of life, and the wonderful cause of most surprising phenomena known under the names of sympathies and consents.’[7]

If one cuts the head of a duck off at a blow, it does not remain motionless but moves, flaps its wings and flutters along, as though it meant to make its escape. It is said that the Emperor Commodus caused the heads of the ostriches in the circus to be shot off with curved arrows, and that the birds still ran on till they reached the goal. If we cut the head of a dog off with a hatchet, we see that the trunk wags the tail. There is a curious irony in the fact, but it need not shock us, for the animal no longer feels. If an irritant is applied to the skin, it draws its tail between its legs as though it were afraid, although it is headless.

V

A difficult question confronts us here. There are some physiologists who maintain that the maid is blind, and that she performs her work without knowing what she does; that she pulls the cord when the bell rings, heats the stoves, cooks, cleans the utensils, sweeps the house, gives the rubbish to the dustman, and so on—but all this without power of discernment, acting like an automaton, unable to make the slightest change in what she does merely from habit. Others, again, maintain that she does possess a few fragments of intelligence, that at certain times she reasons too, and that the soul of the house does not dwell in the master alone.

It is a very difficult question; because, if it can be proved that the maid is blind and does everything from habit, one may also say that the master—poor man!—does not see much either, and that he has certainly not been able to teach the maid anything.

I say the question is difficult also because the names of the greatest living physiologists are connected with it. Goltz and Foster took a frog, destroyed its brain, and then plunged it into a vessel full of water. If the frog were then touched it might be seen, like other frogs in similar circumstances, to respond by swimming about and even jumping out of the vessel. The water was then warmed up to 40°. The frog remained motionless, nor did it feel that the water was growing hot; it did not try to leap out, and thus allowed the heat to increase until it was boiled without making any movement which might indicate sensation. Therefore the spinal cord alone cannot think. The frog moves like a machine whenever it feels those stimuli to which it is accustomed (like an automaton of which one must press a certain knob in order to produce a particular movement); it is indifferent to everything else, allowing itself to be burnt and boiled and never moving, because no pain is felt.

My friend Tiegel, professor of physiology in Japan, made another experiment. He took a snake and severed the head at a blow. While the trunk was writhing on the ground he touched it with a red-hot iron bar, and the snake wound itself round it and did not desist, although its flesh was burnt and skin charred. And so, in this case too, the spinal cord producing these movements is unreasoning.

But how to explain all the other apparently reasoning acts?

The structure of the nerve-centres can itself give an appearance of intelligence to results which are purely mechanical. Let us assume that the nerve-paths passing to the various muscles from one side or the other transmit more or less easily the stimuli given off from the spinal cord. A drop of vinegar having been put on the leg of a frog, as before mentioned, certain muscles will at once move—that is, those of which the nerves oppose the least resistance to the stimuli produced in the centre. But if the animal cannot remove the cause of the irritation, the latter accumulates in the spinal cord, so increasing in force that the nervous tension makes a way for itself along more resisting paths, thus giving rise to other less usual movements.

VI

During my medical career I had more than once an opportunity of seeing the human spinal cord injured or severed. The most interesting case was that of a peasant, who, in falling from a tree, had severed the spinal cord in the dorsal region a little below the shoulder-blades, with a pruning hook. He moved his arms, spoke, but did not feel the lower part of his body any longer, nor the pain which a wound he had on the shin-bone would otherwise have caused him, although the leg moved whenever we touched the sore in order to treat it.

Marshall Hall proved that all generative acts are dependent on the lower part of the spinal cord, and Brachet tells of a soldier who became the father of two children although the lower half of his body was paralysed and quite without feeling. The only thing we do not find in an animal with the spinal cord severed are those irregular movements of the part separated from the brain, corresponding by their spontaneity to those we call voluntary.

Frogs and other animals of which one has cut the spinal cord are in general motionless and paralysed in the parts separated from the brain; we must touch them in order to make them move. If one pinches or slightly presses the hind-paw of a dog with the spinal cord severed in the dorsal region, he moves it or draws it away, but does it unconsciously, as we do if we are touched while asleep. If the stimulus is strong, he moves the other leg and his tail; if stronger still, he moves his whole body and trembles.

Even when the brain is wanting, slight stimuli produce a wagging of the tail; strong stimuli the drawing of the tail between the legs. This proves that certain characteristic phenomena of fear are produced without any participation of the will or consciousness.

The liveliness and restlessness so characteristic of youth arise from the greater excitability of the nervous system, which one always notices in young animals. The age, race, and bodily condition render very dissimilar the reflex movements by which animals deprived of their brain respond, even when they are excited in the same manner. The differences observable in character correspond to anatomical and functional differences of the nerve-centres.

As it is impossible to find two men having all parts of their brain or spinal cord exactly alike, we infer that these differences in the structure of the nerve apparatus materially influence other functional differences which seem to depend on causes of a higher order known under the generic name of will. What many call free-will is only a fatal necessity, an indissoluble chain of causes and effects, of physical and mechanical actions, of automatic and unconscious reactions in the living machine.

VII

In order to understand certain phenomena of fear, we must first study a few peculiarities presented by the excitable portions of the nervous system. If one stimulates the nerve running through the frog’s leg by very slight electric currents which are incapable of producing a contraction of the muscles, the force of the current may be slowly and evenly increased without the leg moving or in any way responding. This experiment shows us that the motor nerves do not respond to the stimulus as such, because the latter may be very strong without producing any visible effect, but that it is the rapid variations and changes which cause the convulsive movements.

Any pain or fear assailing us unexpectedly causes a great disturbance in the organism, but have a less serious effect when slowly developed.

There is always a more energetic response during the first moments of a sensation. This fact is true of all phenomena of the nervous system, and it is therefore unnecessary to give examples of what everyone knows from experience. This depends also upon the fact that the nervous system discharges a part of its energy at every reaction, so that when the animal is very weak it responds no more after the first two or three times.

We now understand why slight, unexpected emotions produce such intense perturbations in the organism, while very serious events for which we are prepared have in proportion much less effect.

VIII

Pliny, in speaking of fear making one close the eyes, relates that amongst twenty gladiators scarcely two were found who did not wink when suddenly menaced.[8]

It is striking that such slight causes produce movements so pronounced that we are not capable of suppressing them. We know that our friend will certainly not poke his finger into our eye, but the conviction that it is a joke does not suffice. Even if a thick pane of glass were between us and the approaching hand, with all the force of reason and will, many would be unable to avoid shutting the eyes, as though there were in us two natures: one, animal and unreasoning which commands, and the other human and intelligent which succumbs.

Again, when a gnat or a grain of dust gets into our eye, the eye closes irresistibly by an automatic mechanism quite independent of our will. Sometimes there is not only one contraction, but a somewhat complicated series of movements excited in parts distant from the stimulus.

As a convincing example, I shall communicate what I observed in an investigation of deglutition. This act, performed unceasingly during eating, is by no means voluntary, for if we try to repeat it a few times in succession we notice at once that, as soon as we have no saliva in the mouth, every effort to swallow is in vain. In order to swallow it is necessary that a morsel of food or some fluid should touch the mucous membrane of the posterior portion of the mouth. The sensory nerves stimulated in this way communicate to the spinal cord that a body is at the entrance of the œsophagus which must be sent to the stomach. Immediately a succession of orders is issued, one after the other, by the spinal cord, so that first the upper part of the œsophagus contracts and propels the morsel a short way down, then a further order causes a contraction of the next part, then comes another order whereupon a part still lower down contracts, and so all the successive portions of the œsophagus transmit the morsel one to another by means of various separate orders until it reaches the stomach.

We have, therefore, in our nervous system mechanisms which work automatically, and produce a series of contractions directed to one object, which may, at first sight, appear voluntary, but is, in reality, mechanical and unconscious. Some of these mechanisms we bring into the world with us. If one puts a finger into the mouth of a new-born child it begins to suck. It is a machine working without discernment, as if one had touched the spring of an automatic doll; no one teaches the child, he need not learn it at all in fact, for the fœtus in the womb makes exactly the same movement. So it is with the chicken, which pecks when just escaped from the shell. In this case, what gives rise to the movement is no longer immediate contact as that of the finger in the mouth, but the impression of light and sight, which indeed is nothing else but contact with distant things by means of the rays of light. Scarcely has the image of the grain formed itself in the eye of the chicken but it pecks at it.

It suffices to observe our movements with a little attention, in order to be convinced that a greater number of them are automatic than one thinks. When we step out of bed in winter and thrust our naked feet into our slippers, the foot has scarcely touched the cold leather but it withdraws, and an effort is necessary in order to resist. We notice, too, that when the shoemaker measures us for a pair of shoes, it is somewhat difficult to keep our foot still even though he does not tickle us. When one touches iron, a cup, or any other object which is very hot, the hand lets go at once. This is a very useful circumstance, because we often let go of a thing which might injure us before we have even become aware that it burns or pricks. And when we have lost consciousness through illness or any accident, the body takes care of itself, as during sleep, by automatically removing itself from anything which pricks, burns, chills, stings, or presses, and so on. If the pain produced by burning is faint, only the one side of the body moves, if it spreads and grows stronger, it affects the opposite side also, and in the highest degrees, the whole body.

This law, which was established by Pflüger, holds good for normal and uninjured animals as well as for those from which the brain has been removed and which are unconscious. It shows us that the postures and movements of the body, so characteristic of a man responding to sudden pain, do not depend on his will. All that is most characteristic in the phenomena of fear: the palpitation, shortness of breath, pallor, screams, flight, trembling, are reflex movements. The more physiology advances, the more the domain of free-will is restricted, and the greater the increase of involuntary movements.

CHAPTER III

THE BRAIN

I

An animal deprived of the brain is a machine which requires external stimuli in order to move. An uninjured animal is also a machine, but it differs from the other by that power in itself which renders it capable of moving and acting.

When an animal with its brain removed is touched on any point of its body quite lightly, it does not respond at once to this external stimulus, and only when these light touches are often repeated is a reactionary movement excited. There are some very wonderful experiments which made a great impression on me, when I first saw them performed by my friends Kronecker and Stirling in the laboratory in Leipzig. They took a decapitated frog, and fastened between the toes of one of the hind-legs a pen, which made marks on the paper of a rotating cylinder whenever the frog moved. Between the toes of the other leg they fastened the wires of an electric current; a pendulum alternately opening and closing the current in such a manner that an interrupted stimulus was obtained. It was strange to see how the headless frog responded regularly for hours. When stimulated by a weak current (so weak that it could not be felt on the tongue) more numerous repetitions, perhaps thirty, were necessary before the frog responded by a spasmodic movement. If the stimulus were stronger a much smaller number was sufficient to cause reaction, and this continued until life was extinct.

Stimuli accumulate in the spinal cord. We all know it from experience; when we have something in the throat which tickles us, the slight, and at first scarcely perceptible, irritation becomes almost unbearable if it continues, compelling us to cough in order to remove it. As the Italian proverb says, one cannot disguise a cough. Even a slight tickling of the skin has the same effect, and in the functions of reproduction the repetition of slight stimuli produce greater and more ungovernable reflex movements.

There are, however, impressions which remain longer accumulated in the brain before their energy finds expression in muscular activity. Sometimes a part of the nervous system charges itself slowly, like a Leyden jar under the influence of weak electric sparks, the tension of the nerve-cells remaining, as it were, hidden, until suddenly discharged by a contact or some very slight impression. We are astonished; it seems an accidental explosion to us, an effect out of all proportion to the momentary cause, forgetting that fire glows under ashes, that the force had been slowly accumulating, and so we believe we have accomplished the act by means of the will.

The aptitude of the nerve-cells to accumulate and preserve external impressions is such a leading fact in physiology that I do not know any more important one.

If I were asked the difference between the brain and the spinal cord, I should say that the brain is more capable of accumulating impressions, not because of the difference of its substance, but because in it the nerve-cells serving this purpose are found in greater abundance.

The manner in which the brain has formed itself in the evolution of the animal world will render the comprehension of its activities easier. Let us consider the simplest creatures, those possessing, so to speak, only a spinal cord. The nerves branching off from the upper part to the nostrils, eyes, ears, mouth, and elsewhere, were subjected during the long series of generations to more continuous stimuli than other nerves. The cells placed at the roots of these nerves were constantly excited by impressions from the external world; chemical processes and combustion would be more rapid in them, hence the necessity of a more copious flow of blood to those parts which were in greater activity. These cells multiplied rapidly at the roots of the organs of sense, gradually covering a wider field. As the animal structure became more perfect during evolution, and the relations of the animal to the outer world increased, the more abundant and active the cells at the roots of these nerves would become. We must not think here of one individual, although individual exercise does strengthen an organ, but must fix our eyes on the interminable chain of generations, all working in this direction.

It was heredity (by which we still transmit to our children the structure and functions acquired by the nerve-centres) which, through the incessant efforts of our progenitors, enlarged this fertile field, until at last it resulted in the mass of the brain.

If, on visiting a museum of comparative anatomy, the reader will look into the glass cases set apart for the study of the nervous system, he will see that the lowest animals have only a spinal cord, or a very small protuberance at the place corresponding to the brain. As the animal structure becomes more complicated, there is a visible increase of the protuberance, which enlarges gradually the nearer one approaches the superior animals, until at last it reaches its maximum size in man.

II

One of the greatest experimenters of modern physiology, Flourens, had already given it as his opinion that the whole cerebral mass performs the same functions in all its parts, and that if one portion be taken away, those contiguous to it charge themselves with its offices. This affords a partial explanation of the fact that wounds of the brain are far less dangerous than those of the spinal cord. It is always a great wonder, even to us physiologists, every time we convince ourselves on living subjects that the brain is without feeling. Men have been seen who suffered great portions of their brain, which protruded from the skull, to be cut away, and sick drunkards or madmen, who, through the wounds in their head, seized hold of the brain with their hands and destroyed it.

Only in the last few years have physiologists succeeded in preserving alive for some time dogs of which nearly all the convolutions of the brain had been removed. Professor Goltz brought a dog in this state from Strasburg to London, in order to show the phenomena which an animal then presents, at the International Congress of Medicine. I extract a few fragments from Professor Goltz’s work,[9] in order to give an idea of the phenomena exhibited by dogs when deprived of a great part of their brain.

A brainless dog has a stupid, inane look. One reads idiocy even in his eyes. His movements are slow and uncertain. It seems as though he needed far more time than usual to come to a decision. His gait is like that of a goose, there is something inexpressibly strange and comical in it. The animal always walks straight on like an automaton. If he meets another dog, he steps over him if he is little; if he is big he may lift him with his head, or knock him down, but on he goes. He tries awkwardly to step over every object he meets, although by simply stepping aside he might pass on without hindrance. He only finds his dish of food with difficulty, smell guiding him better than sight; he snaps stupidly at everything he sees, even biting his own paws till he howls with pain. He can no longer find the fragments of bone that fall out of his mouth while chewing.

Dogs like these are no longer capable of learning anything, and one might almost say that they have forgotten what they already knew; for instance, they no longer give their paw to their master, as they used to do. Their whole intellectual life is extinguished; only when they hear a knock at the door do they bark, but they always begin too late. Two dogs that hated each other, bit each other when they met, even after both had lost a great part of their brain. Memory diminishes in proportion as larger quantities of the brain are removed, and disappears wholly when nearly the whole organ is wanting.

III

In order better to understand the working of the brain, we may divide it in imagination into two parts: a lower, situated at the base of the cerebral hemispheres, which forms the direct continuation of the spinal cord and is the centre of those movements which arise involuntarily during emotion; and another part in the upper story, as it were, which consists of the cerebral convolutions, is also in connection with the spinal cord, and must be considered as the seat of voluntary movement.

The enormous difference between the mind of a man and that of a child exists because in the latter the upper story of the brain is not developed, the convolutions are scarcely indicated, the organs of will and speech are wanting. As the large pyramidal cells appear and increase, the child acquires intelligence and speech; connections are established with the lower story in order to set muscles and organs which were before inactive into movement. But the difference between these two stories of nerve-centres continues during the whole life. I shall explain this by a few examples. A man is paralysed in consequence of some injury which prevents the upper story of his brain from communicating with the spinal cord. Hands and arms no longer move under the influence of the will, but when some long-expected person appears, or some sudden shock is given to the emotional sphere, he will be able to lift his arms. There is a paralysis of the facial nerve in which the voluntary closing of the eye is impossible, but if anyone makes a movement, as though he were going to poke his finger into the eye, the lid closes instantly. Later, we shall instance men who have remained dumb for a long time, and have regained their speech in consequence of a fright.

Dogs deprived of a large part of the upper story of the brain make no sign of recognition when they see themselves threatened by the whip, but if it is cracked they scamper off hurriedly, or rush forward at it. A mouse with its hemispheres and optic thalami removed remained undisturbed by every noise but that resembling an approaching cat, when it jumped and fled.

By means of injuries to the brain physiologists can easily check the activity of certain voluntary movements. If the peduncles of the cerebellum and certain points of the cerebrum are injured, dogs can be made to go either only to the right, or to the left, continually backwards, or in a circle, as though they were in a circus. The will of the animal is still in existence, but all his efforts are, as often with us, fruitless. In spite of himself his body is drawn in the direction determined by the lesion of the nerve-centres. Claude Bernard tells of a brave old general who, by a cruel irony of fate, could only march backwards.

Many physiologists have of late years tried to establish with precision the point of the brain which is the seat of emotional expressions; that is, that part, the destruction of which obliterates every expression of fear or pain in the animal, although allowing life to continue. One of the latest works published concerning this is by Bechterew. His observations show that a dog, in whose brain the corpora bigemina and quadrigemina have been destroyed, still barks and shows his teeth if anything loathsome is given him to eat, or if something smelling disagreeably is put before him; but that he is bereft of all expression of disgust and loathing after the two optic thalami have been removed. Hence Bechterew concludes that the paths of transmission along which pass the involuntary commands which cause the muscles to contract, in order to express the emotions, concentrate in the optic thalamus, which is one of the deepest parts of the brain. The upper story of volition and the lower of the emotions have here their point of union, whence to excite in the muscles of the organism all the characteristic movements of the passions.

IV

Let us now see what instinctive qualities we inherit from our forefathers, and what others we acquire through our own experience.

Long ago Galen performed a very simple and instructive experiment. He cut a kid out of the body of its mother, laid it immediately on the ground, and, near its head, dishes in which were oil, wine, honey, vinegar, water, and milk. He then stood to observe the first movements of the animal. After trembling a little, the kid got up, scratched itself, smelt a few of the dishes, and at last drank the milk.

There are birds which, scarcely out of the shell, catch flies with such precision that one is astonished at their bringing with them skill such as must usually be acquired by long practice. Certain butterflies, on leaving the cocoon, fly at once into the air, directing their flight with the most perfect accuracy towards the flowers, to suck the nectar from their cups.

We shall return to this point when we investigate fear in children. Let us here only state that, at his birth, man is far less perfect than many animals. He must acquire by education and experience much knowledge of which animals are possessed at the beginning.

The less care parents give to their young, the more completely do they furnish them through heredity with instinctive knowledge; the less considerable this inheritance, the more care and attention must parents give to their offspring in order to keep them alive.

This apparent inferiority in the gifts of instinct at birth is, as it is with the gifts of fortune, fully compensated for by the greater capability of those animals to increase their intellectual capacity by education, and by the work of their own experience to surpass by far animals more favoured by instinct; so it is with man, who subjugates them all.

Let us think of the tremendous difficulties which walking presents to man. Children are at first very much afraid of falling, even before they have experienced such a thing. Every movement is performed with difficulty; it is at first a task painfully learnt; gradually it becomes less a matter of reflection, until at last one can scarcely call it voluntary. We may not call it automatic, because when the will to make us walk is wanting we do not move, but when we have once set out on a walk, or to make a journey, we may go on for a long time without reflecting in the least that we are walking.

Ribot[10] tells of a violoncellist who suffered from epileptic vertigo, during which he became unconscious. He earned his living by playing in the orchestra of a theatre, and it was often noticed that he continued playing in time, even after he had lost consciousness. It has happened to all of us to read aloud without understanding what we have read, or absent-mindedly to write one word for another, and many will have experienced such extreme fatigue that they have slept while walking. There are endless phenomena proving that movements which at first cost a great effort of the will, become at length so habitual that we perform them without being aware of it.

Now what is the cause of this transformation of voluntary into automatic movements?

When we first try to execute a series of complicated movements the brain must work hard. If the cells of the upper story—that is, of the convolutions—do not take part in it, it all comes to nothing; the assistance of all the organs of sense is necessary in order to shed light on the confusion of orders and counterorders which must be sent to all the fibres of the muscles. The work is accomplished under the direction of a competent, enlightened administration; but through repetition of the same work, easier paths, broader lines of communication are formed in the lower story of the brain, and gradually the same work can be performed by the cells of the lower part—that is, without the co-operation of the will. This is easy to understand. The oftener a thing is repeated, the more the mechanism tends to become permanent, and it ends in the work being despatched by the less noble parts of the brain.

The serious aspect of the question is, that physiologists would like to catalogue many qualities which we have always considered as the most noble of our character, the most sublime feelings of human nature, amongst the automatic movements and more material instincts in the lower story of the brain.

For instance, for the maintenance of our species the love of the mother for her children is indispensable. The lower animals that produce a numerous offspring may carelessly abandon them, but when the progeny is sparse, there is no other way to preserve the species than through the greater and more prolonged attention on the part of the parents.

Let us for a moment study the character of the monkey. I quote from the celebrated book by Brehm, who conscientiously relates what he himself noticed.

'When the monkey-suckling is unable to do anything for itself, the mother is all the more gentle and tender with it. She occupies herself with it unceasingly, sometimes licking it, sometimes running after it or embracing it, looking at it as though revelling in the sight of it; then she lays it against her breast and rocks it to sleep. When the little monkey grows bigger the mother grants him a little freedom, but she never loses sight of him; she follows his every step and does not permit him to do everything he likes. She washes him in the brooks and smooths his fur with loving care.

'At the least danger she rushes to him with a cry, warning him to take refuge in her arms. Any disobedience is punished with pinches or cuffs, but this seldom happens, for the monkey does not do what its mother objects to. The death of the young one is, in many cases, followed by that of the mother from grief.[11] After a fight monkeys generally leave their wounded on the field; only the mothers defend their young against every enemy, however formidable. At first the mother tries to escape with the young one, but if she falls, she emits a loud cry of pain and remains still, in a threatening attitude, with wide-open mouth, gnashing her teeth, and menacing the enemy with outstretched arms.’

Davancel tells of the profound emotion he experienced after having killed a monkey. 'The poor animal had a young one with her, and the bullet hit her in the region of the heart. She made a last effort, placed the young one on the branch of a tree and then fell down dead. I have never felt,’ he says, 'greater remorse at having killed a creature, which, even in dying, showed feeling so worthy of admiration.’[12]

Whether this is instinct or affection, whether there is any difference between the love of man and of the monkey, I do not feel called upon to decide. I acknowledge that it is necessary for the maintenance of the species that things should be thus, nor need our admiration for mechanisms made in this way suffer any diminution.

I do not think I deserve praise for loving my mother. I remember what she did for me; and even if all our affection were only a simple automatic correspondence of instincts, if I knew that neither had the power to act otherwise, I should be just as glad to be constituted in such a manner that I cannot repress the throbbings of my heart whenever her face rises in my memory. I do not think that my tears and sorrow show less of love on that account.

And if I still feel myself drawn to the grave of the mother who died long years ago, thus cherishing her memory by visiting it in the greatest joys and sorrows of my life, I am glad to be an automaton feeling the religion of love in this renewal of the grief and tears of the last farewell.

CHAPTER IV

THE CIRCULATION OF THE BLOOD IN THE BRAIN DURING EMOTION

I

When we have drawn on a pair of very tight gloves, we feel, if we pay attention, a slight throbbing in the fingers, corresponding to the rhythm of the cardiac pulsations. This throbbing arises because, by every contraction of the heart, one hundred and eighty cubic centimetres of blood—that is, about as much as can be contained in an ordinary drinking-glass—are driven out of the cavity of the thorax. As this wave of blood penetrates the various organs of the body they swell, as is the case with the arteries which dilate at every pulsation and then resume their former volume. When the hands are unconfined we notice nothing, but if we squeeze them into gloves, or our feet into tight shoes, we feel something beating in fingers and toes. This is the blood gushing in, and as the skin cannot yield as in ordinary conditions, the extremely delicate nerve-filaments which branch into it are pressed at every pulsation. If our finger swells from a whitlow, an inflammation, a knock or a burn, immediately the physiological pulsations, unnoticed before, become continuous, causing an acute, stinging pain. The blood flows more abundantly to the inflamed part, the elasticity of the tissues diminishes, the skin becomes more unyielding, an increased pressure on the nerves ensues, and these, rendered more sensitive through the injury, communicate a painful sensation to the brain which pricks unceasingly, keeping time with the rhythm of the heart.

In no organ is the supply of blood so abundant as in the brain; it is sufficient to state that one-fifth of the blood in our body goes to the head. Often, when lying on our side with our cheek on the pillow, we hear the waves of blood passing from the heart to the brain. The arteries, in pulsating, raise the skin, and this movement occasions a slight friction against the pillow, which then propagates itself to the ear. But it is not the beating of the blood against the walls of the vessels, as we feel it on the carotid artery of the neck, or on the radial artery of the hand and elsewhere, which most interests us. A whole world of important facts in the physiology of the emotions and in the circulation of the blood would still be unknown if physicians were still only feeling the pulse, as has been done from the earliest days of medicine until now.

With the old methods we should never have succeeded in observing the spectacle of continuous and ever-varying changes which the movement of the blood operates in the brain, the hand, or the foot.

The physiologist used to be like a man wishful to study the life of a city, and only able to do this by looking down from a terrace at the coming and going of the crowd, the perpetual stream of people in the street. Only of late years have we succeeded in penetrating into the houses by the roof, in spying out the inner life of each family, in studying the irrigation of the organs by the blood while they are at work or in repose.

The pulse in the finest branches of the vessels and in the inward recesses of the organs is such a subtile, delicate phenomenon that we need the assistance of special instruments to intensify it before we can study it. I shall not do as many naturalists do, who think they should conceal the artistic side of their investigations from the fear of desecrating science.

I know that every experimental work possesses an interesting side, which is quite lost owing to the aridity and severity with which scientific treatises are written, and I therefore abandon myself to the recollections of my investigations, careless of following the style of popular scientific books.

II

The first work which I published upon the circulation of blood in the human brain brings sad recollections to me. It was in June 1875 that my friend, Professor Carlo Giacomini, invited me to visit one of his patients in the syphilitic ward. It was a peasant woman, thirty-seven years of age, who, after having borne six children, had been infected by her husband with the most terrible disease to which a mother may fall a victim. For nine years the deadly poison had raged in her bones, and, with only short intervals of respite, had corroded a great part of the skeleton and destroyed the upper part of the skull from the nasal bones to the occiput. Medical art had proved powerless to arrest the disease. When Professor Giacomini took the woman out of pity into the hospital, her face was disfigured, her body was covered with sores and scars, the skin of the head was detached in various parts, the corroded skull had a blackish colour, like dead bones encased in living flesh.

It was after hearing from this unhappy woman the story of her misfortune, and during the intense emotion which pity for her aroused, that I saw for the first time, through the fissures of the decayed bones, the movement of the uncovered brain. Even to-day, eight years later, when I think of that moment, a shiver runs over me as it did then.

The patient recovered strength after energetic treatment, and was able to walk about the garden after a few weeks. It was then that we began to study her brain. I shall not describe the various instruments we constructed, but only remark that we lost much precious time with different attempts, and when we were at last ready, the most favourable time was already past, the wound was covered with a thick scab, which dulled the pulse of the brain. Nevertheless, we made some rather important observations, the results obtained being the most complete up till that time in the physiology of cerebral circulation.

In order to give an instance of the delicacy of the apparatus, and to prove the accuracy of our investigations, I mention the following circumstance. One day we were assembled in the laboratory of Professor Giacomini, intent on studying the brain of the patient, who was sitting in her arm-chair, and seemed absent-minded. There were a few spectators in the room, who were told to remain quietly behind the patient’s back. In solemn silence we observed the curve marked by the cerebral pulse on the registering apparatus. Suddenly, without any external cause, the pulsations rose higher, and the brain increased in size. This striking me as strange, I asked the woman how she felt; the answer was, well. Seeing, however, that the circulation in the brain was very much altered, I examined the instrument carefully, to see whether it was all in order. Then I asked the patient to tell me most minutely what she had been thinking about two minutes before. She said that, as she had been looking absent-mindedly into a bookcase standing opposite to her, she had caught sight of a skull between the books, adding that it had frightened her by reminding her of her malady.

This poor woman was called Margherita; she was rather timid, but willingly allowed herself to be examined and studied, full of confidence in us, who vied with each other in showing her polite attentions. Her children often visited her, but she was ashamed to go back to her native place with her terribly disfigured face, preferring to remain away from her family and perform the duties of nurse to the other invalids in the hospital. After many years I felt a wish to see her again. As I pressed her hand to encourage her, she told me that she had at last given up the wish to die.

III

Chance furthered the continuation of these observations, new opportunities for this study soon offering themselves in Turin and elsewhere. In the lunatic asylum I found a boy a portion of whose skull was wanting. In the year 1877 I came across a man in the hospital of San Giovanni, who had an opening in his forehead which seemed made on purpose for examination; and finally, last year, I was able to repeat and conclude my investigations on a perfectly healthy man who had also a hole in his skull. As yet I have had no opportunity of publishing the observations and experiments made on this man.

How anxious and agitated we are when we enter upon a new field of science; when, at every step, the doubt arises whether some important phenomenon may not have escaped us! How we are tormented by the fear of not being able to face the most vital questions, nor to find out those phenomena most fruitful in results and most subtile! What trepidation overcomes one before one writes down even a few lines in the book of science!

Even amongst physicians it is not easy to find any who are able to write down the history of any fact or observation. The majority of them only know how to relate things in the same dogmatic words with which they are described in treatises, and only a few take the trouble to examine the development of an idea. And yet, in the study of human nature there is nothing more interesting than to follow the different phases of a problem, to see whence a thought arose, to know the first means by which nature was interrogated, then the sudden changes of method, the incidents, the errors and corrections, and at last the victory which crowns our labour and wins a fact for science. I believe if it could be seen near at hand how a research develops in the laboratories, the followers of the experimental sciences would be greater in number.

It is a work of patience. The only difficulty consists in gradually learning the language of Nature, in finding out the way to interrogate her and compel her to reply. In this struggle, in which we, humble pygmies, fight continually in order to wrest from Life its secret, there are moments of intoxicating emotion, rays of light amongst the shadows, which excite the imagination of the scholar and the artist.

IV

The second case, which I studied in company with Dr. Albertotti, was that of a boy eleven years of age, with an agreeable physiognomy and very beautiful physical proportions. He had scarcely reached his second year when he fell from a terrace, fracturing his skull and causing a severe concussion of the brain. After two years and a half he began to suffer from epileptic fits, and later, signs of insanity appeared which obliged his relatives to send him to the lunatic asylum in Turin.

When I saw him in February 1877, he had a large opening in the skull, a little above the right eye, and covered with skin; it was as big as the palm of his hand, and in the pit of it one could feel the pulsing of the brain. The terrible fall had for ever arrested his intellectual development. He was gay, smiling, and lively, like a big baby, but he could not speak. It was a saddening circumstance that in the midst of this ruin of his mind one single higher idea had remained, a remnant of his earlier intellectual life, a motto which he constantly repeated: 'I want to go to school.’

Of all the human cases I have studied, the observations made on this boy gave me the greatest trouble. As I had to do with an idiot, the least obstacles became great difficulties. No apparatus could be applied without his becoming restless, snatching it from his head, and breaking everything which fell into his hands. I had to confine myself to a few observations which could be made by surprising him while asleep. But he did not sleep regularly; I have often found him still awake, even when I made my nightly visit at a very late hour. It was more than sleeplessness, it was a nocturnal excitement, which presaged the storm of an epileptic attack. I have seen him the victim of the most terrible fits, while, on the nights following, his sleep was so deep as to leave one in doubt whether it was a natural phenomenon.

In the period of exhaustion and stupor, the blood-vessels of the brain seemed to relax, and at every contraction of the heart the pulsations became stronger. A faint noise which did not wake the patient was enough to produce a change in the brain and a more abundant gush of blood. It sufficed to touch him, or to approach him with the lamp: immediately, the volume of the brain increased, and a great elevation appeared in the curve of the pulse.

Whenever we called him by name, it seemed as though an impetuous wave of blood rushed into the brain, causing the convolutions to swell. As this was invariably the case, there could be no doubt that the brain was still sensitive to the impressions of the external world, even during a heavy sleep. When the patient was shaken till he woke, I could see the circulation changing little by little, as though the material conditions of consciousness were being restored.

He often spoke a few indistinct words, opened his eyes, or moved his hands, and then slowly fell back into the previous stupor, while we saw the pulse grow weaker, the brain decrease in volume, the rhythm and force of the breathing change.

It was one of the most interesting sights to observe in the stillness of night, by the light of a little lamp, what was going on in his brain, when there was no external cause to disturb this mysterious life of sleep. The brain-pulse remained for ten or twenty minutes quite regular and very weak, and then began suddenly, without any apparent cause, to swell and beat more vigorously. Then the agitation subsided and there was a second period of quiet; then came stronger blood-waves which flooded the convolutions, raising the height of the pulsations, which were automatically marked by the apparatus applied to the brain. We scarcely dared breathe. The one who was observing the instruments communicated with the other, who was watching over the patient, by pressing his hand. Looks full of interrogation and wonder would meet, and exclamations had to be forcibly repressed.

Did dreams, perhaps, come to cheer the repose of the unhappy boy? Did the face of his mother and the recollections of his early childhood grow bright in his memory, lighting up the darkness of his intelligence and making his brain pulsate with excitement? Or was it perhaps only a morbid phenomenon, like the jerky movements of a broken wheel, or the index of a machine out of order, swinging idly to and fro? Or was it an unconscious agitation of matter, like the ebb and flow of an unknown and solitary sea?

What a contrast between the pleasing emotion which this work roused in us and the sadness of the surroundings! Even that quarter of the city in which the asylum is situated has something characteristic about it, which De Amicis compared to the silence and mystery of an Oriental town. Sometimes, when late on winter evenings I made my way along the deserted streets, I could not even hear my own footsteps as they fell noiselessly on the snow. In the long dormitories of the hospital the dim light of the lamp could not dissipate the gloom in the remote corners of the room. However much care I took to glide softly through the room, in order not to disturb the sleep of those poor wretches, many were yet sitting upright in their beds, with staring eyes, seeming to await my coming and ready to shriek at me as I passed. Others, uncovered and naked, in spite of the winter cold, gazed at me with empty, fixed eyes; while others again, bound, to prevent their injuring either themselves or others in their mad fury, followed my steps with wild glances.

What a cheerless sight for a physician, and for me, who came amongst them to study the brain. At the end of these rooms was a little chamber in which I watched my subject. Often I had to interrupt my investigations, and, lamp in hand, go to the most noisy, begging, imploring them to be silent for one minute. It was a waste of breath. Caresses, presents, threats—all were alike of no avail. And when, late at night, discouraged at the failure of my experiments, I left that abode of pain, they were still awake, staring at me with the fixed, impenetrable gaze of a sphynx or the malignant smile of a demon; and when I stepped out into the desolate street again it seemed to me as though I had just escaped from a vision of spectres.

V

Physiologists may wait a long time before finding a more suitable subject on which to study the circulation of blood in the brain than my Bertino. He had a hole in the very middle of the forehead, that seemed made to allow one to look into the skull as an old Greek philosopher once wished to do with the human heart.

To my regret the man only sojourned for a very short time in Turin, and I could only study him during one week. He was a sturdy mountaineer, who suffered from home-sickness, and seemed to be ashamed of his disfigurement. In July 1877, as he was working under the belfry of his village, he was struck on the head by a brick which a mason, working near the roof, at a height of fourteen metres, let fall out of his hand. Bertino fell to the ground as though struck by lightning. He told me that he remembered nothing of it all, not even the blow he had received, and that he regained consciousness after one hour. The earliest recollection which he preserved of the accident was of the moment before the blow. He remembered that he was standing under the belfry watching a comrade dipping bricks into water; then came a period of darkness in his mind, and when he came to himself again he found himself, to his astonishment, in bed, while a surgeon held a watch before him and asked him what time it was. From that moment his mind had been quite clear. The terrible blow made an opening of the size of a shilling in the middle of the forehead. When the splinters of bone had been removed, the brain was seen through the opening, uncovered and pulsating. After having been twenty-four hours in bed, he came on foot to Turin. My friend, Dr. De Paoli, took me to see him. The patient had lost nothing of his power of movement, of his intelligence, his speech, or his memory; he was only very much afraid, and had a perpetual expression of distrust and timidity, even about the most unimportant things, which he tried in vain to conceal.

I must remark that in fractures of the skull the time favourable to study is very short. Large wounds admit with difficulty of the application of the instruments; the smaller ones are better adapted, but they close much sooner from underneath by cicatrisation. When I made the acquaintance of Bertino, the best time was already past; nevertheless the investigations which I made on him are, according to the judgment of competent physiologists, the most complete that have as yet been published.

Eighteen months later I wrote to him, asking him to come to Turin, as I wished to see him. He came at once, and told me that if he had not escaped from the hospital he would have died of melancholy; that he had not been able to bear being in rooms full of dying people, while at home wife and children and fields were awaiting him. The opening in the skull had closed, and the movements of the brain were no longer visible.

VI

Let us now see how the brain writes when it guides the pen itself. I have already collected a few volumes of these autographs, from which I here give a single line as an example, written by Bertino’s brain in the night of September 27, 1877. He was lying on a sofa. I had applied the apparatus which traces the movements of the brain to his forehead, and watched the pen writing on the cylinder while I waited for him to fall asleep. At first the pen traced large undulations, a certain sign of great restlessness in the blood-vessels of the brain; the pulse-lines were considerably modified from time to time in form and height, and this, although profound silence reigned. I might have asked him what he was thinking of, but I did not do it, as I wished urgently to see him fall asleep. At last the undulations began to decrease, becoming lower and less frequent, sometimes separated from each other by long periods of repose, like a lake gradually growing calm, but upon which from time to time a little wave ripples, troubling the smooth surface. At length Bertino fell asleep. Consciousness was extinguished, the troublous thoughts of life had ceased, only the last sentinels of the nervous system were still vigilant. At the slightest noise a wave of blood disturbed the surface of the brain. If the hospital clock struck the hour, or someone walked along the terrace, if I moved my chair, or wound up my watch, or if a patient coughed in the next room—everything, the slightest sound was accompanied by a marked alteration in the circulation of the brain, all immediately traced by the pen which the brain guided on the paper of my registering apparatus.

Fig. 1.—Pulse of the Human Brain during Sleep

After an hour and a half, when I saw that Bertino was breathing quite calmly, with the rhythm and in the characteristic manner of a sleeper, I rose with great caution, approached the pillow on which he had laid his head, and at that point in the curve where is the sign of the arrow, ↓, I called him gently by name, 'Bertino.’ He did not move or answer. If we examine the curve in fig. 1, we find that even before the sign, ↓, four pulsations are somewhat higher than the preceding ones. This first increase in the volume of the brain is due to the very slight noise which I involuntarily made with the chair on rising to approach Bertino.

After calling him by name, the brain wrote three pulsations which have the form of the preceding ones; then the pulse changed, and the pen traced four pulsations, one higher than the other. This is the beginning of what I have called an undulation. During the next pulsations the pulse-line gradually falls until it reaches the previous height. In comparing the form of the pulsations at the beginning of this curve with those at the end, we see that even this very slight emotion, which was not able to interrupt sleep, yet sufficed to produce a great modification. The pulse is stronger, its form tricuspid. We physiologists would say that, from being anacrotic, it had become catacrotic. But the variations which appear in the circulation of the brain during fear are far greater. The reproofs and threats which I uttered to Bertino when he was hindering my experiments by moving his head or hands, the disagreeable things which I sometimes purposely said to him, were always followed by very strong pulsations; the brain-pulse became six, seven times higher than before, the blood-vessels dilated, the brain swelled and palpitated with such violence that physiologists were astonished when they saw the reproductions of the curves, published in the tables of my researches on the circulation of the brain.[13]

VII

In Canada, in 1822, a soldier called Alexis St. Martin was shot at from a short distance. The bullet penetrated the abdomen, perforating the stomach. In a few months, thanks to the treatment of Dr. Beaumont, he was completely healed, only an opening remained in the abdominal walls through which the processes in the stomach could be seen. Several physiologists in America had thus the opportunity of observing the stomach during digestion by looking into its cavity as through a window. The investigations made on this soldier resulted in the statement that the stomach becomes redder as soon as digestion begins. Later, physiologists showed, by other observations, that the salivary glands grow red during mastication, and that the muscles contain more blood when they are at work a long time. We all know that the eyes of anyone who works long become red, that the feet swell after a long walk, and that, in fencing, the muscles of the arms and the hand which grasp the weapon grow thicker.

From these facts we may deduce a law which has no exceptions, namely, that blood is more copiously supplied to an active organ.

The organs of our body are like so many little machines, to which one must furnish fuel if their working power is to be increased. But whereas, in ordinary mechanisms, it is a strange hand which keeps up the fire and directs the movements, our organism is so perfect that in it all apparatus regulate themselves with the greatest harmony of object. In the working muscle the blood-vessels expand, thus more easily to transmit the fuel, and in order that the muscle may convert the chemical force of food into a contraction. In the digesting stomach the circulation is more abundant, because the glands must secrete a greater quantity of juice, the little veins absorb the fluids contained in the stomach, and the muscles contract more quickly in order to mix the food.

Our organism, like all working machines, not only consumes and destroys fuel, here represented by those elements which constitute the blood, but through its activity it also wastes those parts of the body which represent the wheels, axles, hinges, and other parts of a mechanism. At every contraction of the muscles, at every sensation in the brain and nerves during any mental work, there is a wasting of the organs. The blood, flowing continually through all parts of the body in order to feed the flame of life, sweeps at the same time the most remote corners of our organism clean of soot, or the remains of combustion. The vessels become relaxed and expand. Nutrition and organic change become more rapid, the nutritive fluid trickles more easily through the walls of the vessels, the blood flows more quickly, and carries everywhere along with it all the waste products in order to bring them to the kidneys. These purify the blood, and expel, with the urine, the scoriæ of the working organism.

We have seen how the circulation in the brain is accelerated during mental activity, emotion, and in a waking condition; we shall return to this subject in the next chapter, and study more nearly the mechanism by which such variations are produced in all the other organs of the body. This subject is of great importance to physiologists, because in no other way can the slender link which connects psychological phenomena with the material functions of the organism be rendered more evident.

It suffices to increase or diminish in a slight degree the rapidity of the blood penetrating to the brain, in order to cause an immediate change of our 'ego.’ The equilibrium of the molecules in the organs where consciousness has its seat is greatly disturbed by causes which scarcely affect the functions of other parts of the body; because, in the brain, nutrition is more active, and the state of the substances composing it more unstable. The sublimity of psychic phenomena has its root in the greater complication of the material facts by which they are originated. If I were asked which of the functions of the organism were most sensitive to the slightest organic change, I should, without hesitation, answer—consciousness.

VIII

Often, in contemplating the brain of my patients, pondering over its structure and functions, and seeing the blood coursing through it, I have imagined that I might penetrate into the inner life of the brain-cells, might follow the movements which agitate their minute branches in the labyrinth of the nerve-centres; I have thought I might learn the laws of organic change, the order, harmony, the most perfect concatenations; but my mind might work as it listed, and imagination seize the reins, I never yet saw anything, not the faintest gleam, which gave me hope of penetrating to the source of thought.

During my investigations I have discovered the mechanism with which nature provides for a more rapid circulation of blood when the brain must enter into activity; I was the first to admire some of the phenomena in which the material activity of this organ reveals itself; but although I have scrutinised the functions of the brain with the most exact methods of physiological investigation while it was pulsing under my eyes, while ideas were seething in it, or while it rested in sleep, the nature of the psychic processes still remains a mystery.

We all believe that the faculties of the mind are the fruit of an uninterrupted series of natural causes, of physical and chemical actions which lead from the simplest reflex-movements, step by step, to instinct, reason, sentiment, and will; but as yet nothing has been found which might lead us even to suspect, much less to comprehend, the nature of consciousness.

We attain our firmest convictions in the domain of positivism, not from the narrow field of physiology but from the whole kingdom of science. We imagine that the impressions of the external world form a current which penetrates the nerves, and, without either abatement or check, diffuses and transforms itself in the centres, finally reappearing in the sublime form of the idea; this is the notion of the soul held by the philosophers of remote antiquity; this is the base of modern psychology.

We may suppose that thought must be a form of motion, because the science of the present day demonstrates that all intimately known phenomena may be reduced to a vibration of atoms and to a displacement of molecules.

I can think of my brain by the analogy which it must have with that of another; but the bridge which leads me from external to internal observations I cannot find; between physical and psychic phenomena there is a gulf which we cannot pass.

The soul was regarded by the ancients as a harmony. But how this sublime harmony of imagination, of memory, of the passions, and of thought, results from the vibration of the molecules constituting the brain, no one knows. The road which connects psychic facts with the transformation of energy has not yet been pointed out.

I know the chemical transformations which give rise to the mechanical work of the muscles of my hand in writing, but I do not know the processes of my brain which thinks and dictates.

Many have thought and asserted, because the muscles and glands of our body grow heated by their work, that the brain and nerves also grew warm during activity. For my part, I doubt the accuracy of the methods used in these experiments, nor shall I be convinced unless it be clearly shown to be a fact. As the nature of the chemical processes taking place in the brain is totally unknown to us, it may be that the brain grows colder during activity. The question can only be decided when we succeed in eliminating the serious complications which the greater flow of blood produces in such cases.

Till the present day no one knows what parts of the brain are consumed in order to produce thought; no one can imagine how the molecules of the blood penetrate the mass of cerebral cells and become part of consciousness, and neither do we know how, from the joint life of the single cells, something can arise which represents consciousness and sensitivity.

Doctrines are here of no use. When our mind has arrived at the last division of matter, at the last localisation of psychic processes, we feel that it is vain to say we are materialists or spiritualists. All schools are confounded in the nullity of our ignorance. The nature of matter is as incomprehensible as that of spirit. From Lucretius, who gave thirty proofs to demonstrate the materiality of the soul, down to modern materialists, not one step has been taken towards the discovery of the nature of thought. As a matter of fact, many materialists throw down one dogma and build another out of its ruins.

If we reject the hypothesis of the spiritualists, we must, with the same severity, banish from the borders of experimental science those who, in our time, wish to explain, by means of materialistic doctrines, the mechanism generating thought. Anatomy and physiology, the knowledge of structure and of cerebral functions, have scarcely lisped their first words, and dense darkness reigns over the nature of nervous processes, over the physical and chemical movements animating the hidden parts where consciousness has its throne. Let us speak neither of spirit nor of matter; let us candidly acknowledge our ignorance. We trust to the future of science and persevere in the search after truth.

CHAPTER V

PALLOR AND BLUSHING

I

Man has, on the average, four kilograms of blood, and this fluid flows incessantly in a system of tubes, in the centre of which the heart is situated. The arteries carrying the blood from the heart to the surface divide into many branches, separate, extend, and visit all parts of the body, feeding and irrigating them. When the ramifications of the arteries become so small that the eye can no longer see them, as, for instance, in the lips, the finger-tips, the cheeks, the ears, or any part of the skin, they take the name of capillaries. This is meant to indicate that these little arteries are as fine as a hair, but in reality they are very much finer. These last closely connected capillary nets give the skin its beautiful rosy colour. But however much they diminish, dividing and subdividing ad infinitum, they still form a system of canals, with walls and closed on all sides. There must be a wound, a cut, or a contusion, before the blood oozes out of these little vessels. Out of the capillaries the blood passes into larger canals called veins. Several veins flowing into each other form a bigger vein; in the same way as a brook is formed by springs, as the brooks, running into each other, form a rivulet, and the rivulets, a river; so the veins gradually receive the blood in larger streams, until at last they carry it in the great trunk-veins to the heart, which drives it again into the arteries.

The little canals in which the blood circulates are provided with muscular fibre. These may relax and the calibre of the vessels is increased, or they contract and the calibre is reduced. The pallor, so characteristic of fear, arises from a contraction of the vessels; the beautiful blush of modesty, most eloquent of all the revelations of psychic facts, is nothing else but a dilatation of the blood-vessels. These two opposite phenomena do not depend on the heart, since we know that the heart beats more forcibly and rapidly during the emotion of modesty as well as during fright. From the nerve-centres innumerable filaments branch off which are distributed to all the ramifications of the blood-vessels. These are the so-called vaso-motor nerves, which, without our noticing it, act on the muscular fibre of the small arteries and veins, increasing or diminishing the calibre of the little canals in which the blood flows.

The effects of the passions are far more evident on the countenance, with its blushing and sudden pallor, than elsewhere, because in no other part of the body are the blood-vessels so sensitive as in the face. There are two reasons for this, firstly, the nerve-centres act more powerfully on these vessels; secondly, they are more delicate, sooner growing tired, and relaxing at the slightest disturbance of nutrition. Indeed, if we inhale the vapour of a substance which, like that of nitrite of amyl, paralyses the blood-vessels, the face immediately becomes of a vivid red, and anyone making this experiment feels his face aflame in a few seconds. This is the simplest method which we possess for artificially producing the external phenomena of shame.

At different ages and in different persons considerable differences are noticeable with regard to the greater or lesser facility with which they blush or grow pale. I made a long series of investigations in order to see at what degree of temperature the paralysis of the blood-vessels of the hands appears when we dip them into hot water, and at what degree, and after what lapse of time, the hands begin to redden when we hold them in ice-water or in snow, the differences being found to be very considerable.

An old lady does not blush under those moral emotions which used to betray her feelings as a girl; and this, not because age has overcome the timidity of youth, or because the hard struggles of life have blunted her sensibility, but because the blood-vessels of the face have, in course of time, become less yielding. On long walks taken in the sun, one always notices that the faces of babies are redder than those of bigger children, and these, in their turn, are more flushed than those of their parents.

Even persons of the same age do not respond in the same way to the internal or external stimuli which tend to dilate or contract the blood-vessels. It is well-known that all girls do not blush equally at a pleasantry directed to them.

One must not ascribe the difference solely to shyness or modesty, since the blood-vessels of different persons respond in various ways. In a very warm room all the young girls have not equally flushed cheeks, and if we pay attention when, on leaving a company, we touch the hands of a great number of people who have been together for several hours in the same room, we may easily notice the very great difference in the temperature of the hands. In such circumstances, to have warm or cold hands only means to have expanded or contracted blood-vessels.

Besides this action of warmth or cold, which is, so to speak, local, there is another central action much more important to us—that which produces the pallor, or flush of emotion. The nerve-centres can, by means of the vaso-motor nerves, greatly alter the circulation in the various parts of the body, as we all know from the continual changes which the colour of the skin undergoes.

It is not necessary to mention the studies made on animals; the observations which can be made on man suffice to show how this nervous mechanism works. I know several persons whose blood-vessels differ in sensitiveness on the right and left side, and who, therefore, feel the effects of emotion more intensely on one side of the body.

At balls, on excursions in the mountains, and walks in the sunshine, the attentive observer will notice great differences in the colour of the two sides of the face. One often becomes aware of this from the perspiration, which is more abundant on one part of the forehead than on the other. My sister, for instance, when dancing, has one cheek very much flushed, the other less so. With her, it is the right side of the body which possesses more sensitive blood-vessels, which are, therefore, more easily tired by exertion, heat, or emotion; consequently this half of the face becomes redder, and receives a greater quantity of blood.

A few days ago we went for a walk together into the mountains. Looking down from a certain point we saw in the valley the funeral of a child. A girl carried the little corpse, covered with flowers, on her head. The bells of the village were ringing the 'Gloria,’ the funeral train, with the priest at the head, appeared and vanished from time to time between the green trees; children ran behind, carrying candles and scattering flowers. It was a splendid autumn evening.