SOMNAMBULISM.

The phenomena exhibited by a person in the condition of somnambulism are so wonderful, that they have from the earliest times excited the superstitious feelings of the ignorant, and claimed the most serious attention of the learned. To see an individual apparently asleep to the greater part of surrounding objects, yet so keenly awake to others as to be able to perform the most intricate actions without the aid of the senses, is so greatly at variance with the common experience of mankind, as to call up feelings of astonishment, and perhaps of awe, in the minds both of the vulgar and those accustomed to scientific investigation. In those times, when the marvelous exercised so powerful an influence over mankind, and when all phenomena out of the ordinary course of everyday life were regarded as supernatural, it was the prevailing belief that the somnambulist was possessed. Modern science has at last dispelled this idea, and though it has not yet been able to furnish a rational theory of somnambulism which will account for all the manifestations of the affection, it has done much toward elucidating the functions of different parts of the nervous system, and thus to prepare our minds for a full understanding of the subject.

Somnambulism has been defined[109] as “a condition in which certain senses and faculties are suppressed or rendered thoroughly impassive, while others prevail in most unwonted exaltation; in which an individual, though asleep, feels and acts most energetically, holding an anomalous species of communication with the external world, awake to objects of attention, and most profoundly torpid to things at the time indifferent; a condition respecting which most commonly the patient on awaking retains no recollection; but on any relapse into which, a train of thought and feeling related to and associated with the antecedent paroxysm will very often be developed.”

This definition, though unnecessarily long and by no means perfect, will nevertheless suffice for a general description of the chief phenomena of the affection. It accords with the generally received theory. My own views of the nature of somnambulism will appear in the course of the following remarks.

In the introduction to his classical work on the subject under consideration, Bertrand[110] classifies the different kinds of somnambulism according to their causes. He recognizes—

1. A particular nervous temperament which predisposes individuals otherwise in good health to paroxysms of somnambulism during their ordinary sleep.

2. It is sometimes produced in the course of certain diseases, of which it may be considered a symptom or a crisis.

3. It is often seen in the course of the proceeding necessary to bring on the condition known as animal magnetism.

4. It may result as the consequence of a high degree of mental exaltation. It is in this case contagious by imitation to such persons as are submitted to the same influence.

From these four divisions of causes, Bertrand makes four kinds of somnambulism—the essential, the symptomatic, the artificial, and the ecstatic. As he wrote nearly twenty years before the publication of Mr. Braid’s remarkable researches, he was of course unacquainted with that form of artificial somnambulism now known as hypnotism, and which may properly be included in his third class. I shall simplify his arrangement by dividing the several kinds of somnambulism into two classes—the natural and artificial.

Natural somnambulism may occur in persons who exhibit no marked deviations from the standard of health, and in whom there is no very evident nervous excitability. It is usually, though not always, manifested during ordinary sleep, and it is common for authors to speak of it as being necessarily connected with a dream. Thus, Macario[111] says it is a sleep in which the nervo-motor system and all the other organs are put in action under the influence of a dream. A few cases cited from other authors, and from my own experience, will tend to the more complete elucidation of the symptoms of this curious affection. Bertrand[112] quotes the following instance from the EncyclopÆdia:

“The Archbishop of Bordeaux has informed me that when at the seminary he was acquainted with a young ecclesiastic who was a somnambulist. Curious to ascertain the nature of the malady, he went every night to the chamber in which the young man slept. He saw, among other things, that the ecclesiastic got up, took paper, and composed and wrote sermons. When he had finished a page, he read it aloud—if one can apply the term to an action done without the aid of sight. When a word displeased him, he wrote the necessary corrections with great exactness. I have seen the beginning of one of his sermons which he wrote in the somnambulistic state, and thought it well composed and correctly written; but there was an alteration which surprised me. Having used the expression ce divin enfant, he thought as he read it over that he would change the word divin for adorable. He therefore effaced the first word, and wrote the second above it. He then perceived that the word ce properly placed before divin would not do before adorable; he therefore added a t to the preceding letters, so that the expression read cet adorable enfant. The same person, an eye-witness of these facts, in order to ascertain whether or not the somnambulist made use of his eyes, put a card under his chin in such a manner as to prevent his seeing the paper on the table; but he still continued to write. Wishing still to discover whether or not he distinguished different objects placed before him, the Archbishop took away the paper on which he wrote and substituted several other kinds at different times; but he always perceived the change because the pieces were of various sizes. When a piece exactly like his own was placed before him he used it, and wrote his corrections on the places corresponding to those on his own paper. It was by this means that portions of his nocturnal compositions were obtained. These the Archbishop has had the goodness to send to me. The most astonishing among them was a piece of music written with great exactitude. A cane had served him for a ruler—the clef, the flats, and the sharps were all in their right places. All the notes were first made as circles, and then those which required it were blackened with ink. The words were all written below. Once they were in such large characters that they did not come directly under their proper notes. He soon, however, perceived his error, and corrected it by effacing what he had written and writing it over again.

“One night, in the middle of winter, he imagined himself to be walking on the bank of a river and seeing a child fall in. The severity of the weather did not prevent him from determining to save it. He threw himself on his bed in the posture of a man swimming, went through all the motions, and, after becoming well fatigued with the severity of this exercise, he felt a bundle of the bedclothes, which he took to be the drowning child. He seized it with one hand, while he continued to swim with the other, in order to regain the bank of the imaginary river. Finally, he placed the bundle in a place which he evidently determined to be dry land, and rose, shivering, with his teeth chattering as though he had emerged from icy water. He remarked to the by-standers that he was frozen, that he would die of cold, and that his blood was like ice. He then asked for a glass of brandy in order to restore his vitality; but there being none at hand, a glass of water was given him instead. He, however, detected the difference and asked peremptorily for brandy—calling attention to the great danger he incurred from the cold. Some brandy was finally obtained. He drank it with much satisfaction, and remarked that he felt much better. Nevertheless, he did not awake, and, returning to bed, slept tranquilly the rest of the night.”Gassendi[113] had in his service a young man who every night arose in his sleep, descended into the cellar and drew some wine from a cask. Frequently he went out into the streets in the middle of the night, sometimes even he went into the country and walked on stilts, in order to cross a rapid stream which ran around the city. If he happened to awake from his sleep after having crossed this torrent, he was afraid to recross it so as to return home. Gassendi relates that when this man waked in the course of his perambulations he suddenly found himself in darkness, but as he had the faculty of remembering all that had taken place during his dream, and of recognizing the place where he found himself, he was able to grope his way to his bed. The darkness, therefore, which was an obstacle to the exercise of his sight when he was awake, was no impediment when he was in the state of somnambulism.

Dr. Prichard[114] cites from Muratori[115] the cases of Forari and Negretti, which are curious instances of the affection in question.

“Signor Augustin Forari was an Italian nobleman, dark, thin, melancholic, and cold-blooded, addicted to the study of the abstract sciences. His attacks occurred at the waning of the moon, and were stronger in the autumn and winter than in the summer. An eye-witness, Vigneul Marville, gave the following description of them:

“One evening, toward the end of October, we played at various games after dinner; Signor Augustin took a part in them along with the rest of the company, and afterward retired to repose. At eleven o’clock, his servant told us that his master would walk that night, and that we might come and watch him. I examined him after some time with a candle in my hand. He was lying upon his back and sleeping with open, staring, unmoved eyes. We were told that this was a sure sign that he would walk in his sleep. I felt his hands and found them extremely cold, and his pulse beat so slowly that his blood appeared not to circulate. We played a tric-trac till the spectacle began. It was about midnight, when Signor Augustin drew aside the bed-curtains with violence, arose and put on his clothes. I went up to him and held the light under his eyes. He took no notice of it, although his eyes were open and staring. Before he put on his hat, he fastened on his sword-belt, which hung on the bedpost; his sword had been removed. Signor Augustin then went in and out of several rooms, approached the fire, warmed himself in an arm-chair, and went thence into a closet where he had his wardrobe. He sought something in it, put all the things into disorder, and, having set them right again, locked the door and put the key into his pocket. He went to the door of the chamber, opened it and stepped out on the staircase. When he came below, one of us made a noise by accident; he appeared frightened, and hastened his steps. His servant desired us to move softly and not to speak, or he would become out of his mind; and sometimes he ran as if he were pursued, if the least noise was made by those standing around him. He then went into a large court and to the stable, stroked his horse, bridled it, and looked for the saddle to put on it. As he did not find it in the accustomed place, he appeared confused. He then mounted his horse and galloped to the house-door. He found this shut, dismounted and knocked with a stone, which he picked up, several times at the door. After many unsuccessful efforts, he remounted and led his horse to the watering-place—which was at the other end of the court—let him drink, tied him to a post and went quietly to the house. Upon hearing a noise, which the servants made in the kitchen, he listened attentively, went to the door and held his ear to the keyhole. After some time he went to the other side, and into a parlor in which was a billiard-table. He walked around it several times and acted the motions of a player. He then went to a harpsichord, on which he was accustomed to practice, and played a few irregular airs. After having moved about for two hours, he went to his room and threw himself upon his bed, clothed as he was, and the next morning we found him in the same state; for as often as his attack came on he slept afterward from eight to ten hours. The servants declared that they could only put an end to his paroxysms either by tickling him on the soles of his feet, or by blowing a trumpet in his ears.”

The history of Negretti was published separately by two physicians, Righellini and Pigatti, who were both eye-witnesses of the curious facts which they relate.

“Negretti was about twenty-four years old, was a sleep-walker from his eleventh year; but his attacks only occurred in the month of March, lasting at farthest till the month of April. He was a servant of the Marquis Luigi Sale. On the evening of the 16th of March, 1740, after going to sleep on a bench in the kitchen, he began first to talk, then walked about, went to the dining-room and spread a table for dinner, placed himself behind a chair with a plate in his hand as if waiting on his master. After waiting until he thought his master had dined, he removed the table, put away all the materials in a basket, which he locked in a cupboard. He afterward warmed a bed, locked up the house, and prepared for his nightly rest. Being then awakened, and asked if he remembered what he had been doing, he answered no. This, however, was not always; he often recollected what he had been doing. Pigatti says he would awake when water was thrown into his face, or when his eyes were forcibly opened. According to Maffei, he then remained sometimes faint and stupid. Righellini assured Muratori that his eyes were firmly closed during the paroxysm, and that when a candle was put near to them, he took no notice of it. Sometimes he struck himself against the wall and even hurt himself severely. Hence it would seem that he was directed in his movements by habit, and had no actual perception of external objects. This is confirmed by the assurance that if anybody pushed him, he got out of the way and moved his arms rapidly about on every side; and that when he was in a place of which he had no distinct knowledge, he felt with his hands all the objects about him, and displayed much inaccuracy in his proceedings; but in places to which he was accustomed he was under no confusion, but went through his business very cleverly. Pigatti shut a door through which he had just passed; he struck himself against it in returning. The writer last mentioned was confident that Negretti could not see. He sometimes carried about with him a candle, as if to give him light in his employment; but on a bottle being substituted, took it and carried it, fancying that it was a candle. He once said during his sleep that he must go and hold a light to his master in his coach. Righellini followed him closely, and remarked that he stood still at the corners of the streets with his torch in his hand not lighted, and waited awhile in order that the coach which he supposed to be following might pass through the place where light was required. On the eighteenth of March he went through nearly the same process as before in laying a table, etc., and then went to the kitchen and sat down to supper. Signor Righellini observed him, in company with many other cavalieri very curious to see him eat. At once he said, as recollecting himself, ‘How can I so forget? To-day is Friday and I must not dine.’ He then locked up everything and went to bed. On another occasion he ate several cakes of bread and some salad which he had just before demanded of the cook. He then went with a lighted candle into the cellar and drew wine, which he drank. All these acts he performed as usual, and carried a tray upon which were wineglasses and knives, turning obliquely when passing through a narrow doorway, but avoiding any accident.”

Macario[116] cites from I. Franck the case of a young peasant, aged about sixteen, and endowed with a degree of intelligence above his age and condition, who was rendered somnambulic by the grief caused by the sudden death of his father. A few weeks after this event, he dreamed that he saw two unknown and frightful-looking men who advanced slowly toward his bed, and in menacing language ordered him to rise immediately and accompany them, threatening that if he refused they would return the following night and take him by force. This dream had so strong an effect upon him that he became melancholic. Two days afterward, while he was sleeping quietly, he dreamed that his father’s spirit came to him, accompanied by the two men who had previously visited him, and ordered them to seize his son, notwithstanding his resistance, and to carry him off.

The young man dreamed that he was transported through a delightful country of vast extent; he heard the harmonious sounds from flutes and other musical instruments; he saw young people dancing on the charming plains, and he ate to satiety of delicious viands. Immediately the scene changed; his father’s spirit disappeared, and his ferocious companions carried him high up into the air and then suddenly let him fall into a barrel. The servants returning with the cows, found the young man in the stable shut up in an empty barrel, scantily covered, and almost dead with cold and fright. Restored by frictions and warmth, he had no recollection of anything connected with his situation beside the dream above recorded. At the end of a week, he again rose from bed in his sleep, but finding the door locked, he returned and remained quiet. In a short time the disease ceased entirely.

The same author also quotes from Franck the case of a Jewish tailor, who, during the attacks of somnambulism to which he was subject, recited in a low voice his customary prayers in Hebrew. When he came to certain parts he raised his voice, called out aloud, and imitated the gestures of the rabbis in the synagogues. While thus engaged his eyes were wide open, and the pupils insensible to the stimulus of light. Then his face became pale, he presented the appearance of weeping, his whole body was covered with a cold, profuse sweat, and his pulse rose to 130. This crisis was followed by a tranquil prayer, to which sooner or later another access of fury succeeded; and this series continued for an hour or two, or till his prayers had been repeated for the prescribed period.

When strongly shaken he awoke with a startled manner, but if left to himself fell asleep again, and resumed his prayers at the place where he had been interrupted. When awake he declared that he had no recollection of what had happened during his sleep. The paroxysms appeared every day except Tuesday. The patient had a brother who was also a somnambulist.

These cases will give an idea of somnambulism as it has been witnessed by other observers, or as its phenomena have impressed them. The following instances of the disease have come under my own notice.

A young lady, of great personal attractions, had the misfortune to lose her mother by death from cholera. Several other members of the family suffered from the disease, she alone escaping, though almost worn out with fatigue, excitement, and grief. A year after these events, her father removed from the West to New York, bringing her with him and putting her at the head of his household. She had not been long in New York, before she became affected with symptoms resembling those met with in chorea. The muscles of the face were in almost constant action, and though she had not altogether lost the power to control them by her will, it was difficult at times for her to do so. She soon began to talk in her sleep, and finally was found one night by her father, as he came home, endeavoring to open the street-door. She was then, as he said, sound asleep, and had to be violently shaken to be aroused. After this she made the attempt every night to get out of bed, but was generally prevented by a nurse who slept in the same room with her, and who was awakened by the noise she made in the room.

Her father now consulted me in regard to the case, and invited me to the house in order to witness the somnambulic acts for myself. One night, therefore, I went to his residence and waited for the expected manifestations. The nurse had received orders not to interfere with her charge on this occasion, unless it was evident that injury would result, and to notify us of the beginning of the performance.

About twelve o’clock she came down stairs and informed us that the young lady had risen from her bed and was about to dress herself. I went up stairs, accompanied by her father, and met her in the upper hall partly dressed. She was walking very slowly and deliberately, her head elevated, her eyes open, her lips unclosed, and her hands hanging loosely by her side. We stood aside to let her pass. Without noticing us, she descended the stairs to the parlor, we following her. Taking a match, which she had brought with her from her own room, she rubbed it several times on the under side of the marble mantle-piece until it caught fire, and then, turning on the gas, lit it. She next threw herself into an arm-chair and looked fixedly toward a portrait of her mother which hung over the mantle-piece. While she was in this position, I carefully examined her countenance, and performed several experiments with the view of ascertaining the condition of the senses as to activity.

She was very pale, more so than was natural to her; her eyes were wide open and did not wink when the hand was brought suddenly in close proximity to them; the muscles of the face, which when she was awake were almost constantly in action, were now perfectly still; her pulse was regular in rhythm and force, and beat 82 per minute, and the respiration was uniform and slow.

I held a large book between her eyes and the picture she was apparently looking at, so that she could not possibly see it. She nevertheless continued to gaze in the same direction as if no obstacle were interposed. I then made several motions as if about to strike her in the face. She made no attempt to ward off the blows, nor did she give the slightest sign that she saw my actions. I touched the cornea of each eye with a lead-pencil I had in my hand, but even this did not make her close her eyelids. I was entirely satisfied that she did not see—at least with her eyes.

I held a lighted sulphur-match under her nose, so that she could not avoid inhaling the sulphurous acid gas which escaped. She gave no evidence of feeling any irritation. Cologne and other perfumes, and smelling-salts likewise failed to make any obvious impression on her olfactory nerves.

Through her partially opened mouth, I introduced a piece of bread soaked in lemon-juice. She evidently failed to perceive the sour taste. Another piece of bread, saturated with a solution of quinine, was equally ineffectual. The two pieces of bread remained in her mouth for a full minute, and were then chewed and swallowed.

She now arose from her chair and began to pace the room in an agitated manner; she wrung her hands, sobbed, and wept violently. While she was acting in this way, I struck two books together several times so as to make loud noises close to her ears. This failed to interrupt her.

I then took her by the hand and led her back to the chair in which she had previously been sitting. She made no resistance, but sat down quietly and soon became perfectly calm.

Scratching the back of her hand with a pin, pulling her hair, and pinching her face, appeared to excite no sensation.

I then took off her slippers, and tickled the soles of her feet. She at once drew them away, but no laughter was produced. As often as this experiment was repeated, the feet were drawn up. The spinal cord was therefore awake.

She had now been down stairs about twenty minutes. Desiring to awake her, I shook her by the shoulders quite violently for several seconds, without success. I then took her head between my hands and shook it. This proved effectual in a little while. She awoke suddenly, looked around her for an instant, as if endeavoring to comprehend her situation, and then burst into a fit of hysterical sobbing. When she recovered her equanimity, she had no recollection of anything that had passed, or of having had a dream of any kind.

A gentleman of very nervous temperament informs me that upon one occasion he dreamed that his place of business was on fire. He got up in his sleep, dressed himself, and walked a distance of over a mile to his store. He was aroused by the private watchman, who stopped him while in the act of looking through the grating of the door, under the impression at first that he had caught a burglar.

A young lady who some time since was under my care for intense periodical headaches, informed me that, just previous to each attack, she walked in her sleep, but had never any recollection of what she did while in the somnambulic state. Her mother stated that when her daughter was in this condition, she did not use her eyes, although they were wide open, nor did she appear to hear loud noises made close to her ears.

In relation to the activity of the senses during somnambulism, there is great diversity of opinion among those who have studied the affection. This is doubtless due to the fact that somnambulists differ among themselves as regards the use they make of their senses—some availing themselves of the aid they can derive from these sources, while others do not appear to employ them at all.

Thus it is stated that Negretti kept his eyes closed, and yet when a box of snuff was handed to him, he took a pinch without hesitation; and the young ecclesiastic whose case I have already quoted, performed even more complex acts than this.

Castelli, a young somnambulist and a student of pharmacy, performed many astonishing acts during his paroxysms. One night he was found in the somnambulic condition, translating a passage from the Italian into French, and searching out the words in a dictionary. Prichard[117] assumes from this fact that he must have seen the words. He states further, that somnambulists have been known to write and even to correct their compositions, and to do other acts which could not possibly have been performed without sight. While it is certainly true that somnambulists have done all these things, it is equally certain that they have often performed them without the aid of their eyes. In the case of Castelli, a candle was on the table, which some one who saw him extinguished. He immediately arose, and lighted it, although there was no occasion for his doing so, as the room was well lit with other candles.[118] These he had not observed, but was only cognizant of the one which he probably did not see, but which was in relation with him through some more subtle channel.

Many somnambulists are known to have acted as though they saw in rooms which were perfectly dark. A gentleman informs me that his wife frequently walks in her sleep, and performs many somnambulic acts in entire darkness. On one occasion she went into a dark closet, and, opening a trunk, began to arrange the contents. It contained clothing of various kinds, which had been put into it the day before without being sorted. She classified all the articles, such as stockings, handkerchiefs, shirts, etc., without making a single mistake—and without the possibility of being assisted by light sufficient for ordinary eyesight.

Bertrand[119] refers to the case of a young lady who was accustomed to rise from her bed in a state of somnambulism and to write in complete darkness. A remarkable feature of this instance was, that if the least light, even that of the moon, entered the room, she was unable to write. She could only do so in the most perfect obscurity.

In the case of the young lady, the particulars of which, with my experiments, I have related, the sense of sight was certainly not employed, nor were the other senses awake to ordinary excitations.

On the other hand, it is evident that some somnambulists make use of their eyes and their other organs of sense in the ordinary way, when the excitations made upon them are in relation with the train of thought or ecstatic condition which prevails.

Macario,[120] in reference to this point, says:

“Somnambulists are insensible to external impressions, except those which are in relation with their ideas, their thoughts, and their feelings. It is thus that persons, the subjects of somnambulism, will pass before objects or individuals without seeing them, although they may have their eyes open. This phenomenon occurs often to individuals who are fully awake, although in a less degree. Thus when we are strongly preoccupied with any subject, the objects which surround us make no impression on our senses or our mind. Archimedes while meditating on a discovery, was an entire stranger to all that was going on around him. A part only of his brain was awake and active. While thus engaged, Syracuse was taken by the enemy, and he was not diverted from his thoughts either by the chant of victory by the conqueror, or by the cries and groans of the wounded and the dying.”

As regards the sense of hearing, it is doubtless true that somnambulists rarely exercise it. There have been cases in which replies have been made to questions; but such answers have been given automatically, and not as if the mind took cognizance of the subject. A person intently engaged in reading, will often answer questions without suffering his train of thought to be interrupted. When he has ceased his study, he is surprised when told that he has been conversing.

The sense of taste appears to be very inactive in general, though in a few cases it has been manifested. The same is true in even a greater degree with the sense of smell.

The sense of touch is very differently affected, for so far from being diminished in its action, it is invariably unduly exalted. Though the eyes do not see, the ears hear, the tongue taste, or the nose smell, the somnambulist has one sense which is fully awake, and by which he is enabled to guide himself through the most devious passages in dangerous paths.

In this fact it appears to me we have a strong argument in favor of the theory of somnambulism which I have already referred to, and which appears to me to be supported by much additional evidence. I propose this view not without hesitation; but much study of the phenomena of somnambulism, and of analogous states of the nervous system, has certainly tended to convince me of its general correctness, and I am not without the hope that other students of neurology will find it reconcilable with their observations and experiments.

In my opinion, somnambulism is a condition of the organism in which through profound sleep the action of the encephalic ganglia is so materially lessened that the spinal cord becomes able to control and direct the body in its movements.

That the spinal cord even in the waking state constantly exercises this power, is a matter of common observation. I have already alluded to some of the facts which establish this proposition; but, for the purpose of giving as complete and connected a view as possible of all the points which bear upon the theory of somnambulism above enunciated, I shall not hesitate to recall them to the recollection of the reader, and to bring forward other circumstances which appear to be in relation with the question.

If an individual engaged in reading a book allows his mind to be diverted to some other subject than that of which he is reading, he continues to see the words, which make no impression upon his brain, and he turns over the leaf whenever he reaches the bottom of a page with as much regularity as though he comprehended every word he has read. He suddenly, perhaps, brings back his mind to the subject of his book, and then he finds that he has perused several pages without having received the slightest idea of their contents.

Again: when, for instance, we are walking in the street and thinking of some engrossing circumstance, we turn the right corners and find ourselves where we intended to go, without being able to recall any events connected with the act of getting there.

In such instances as these—and many others might be adduced—the brain has been occupied with a train of thought so deeply that it has taken no cognizance or superintendence of the actions of the body. The spinal cord has received the several sensorial impressions, and has furnished the nervous force necessary to the performance of the various physical acts concerned in turning over the leaves, avoiding obstacles, taking the right route, and stopping in front of the right door.

All cases of what are called “absence of mind” belong to the same category. Here the brain is completely preoccupied with a subject of absorbing interest, and does not take cognizance of the events which are transpiring around. An individual, for instance, is engaged in solving an abstruse mathematical problem. The whole power of the brain is taken up in this labor, and is not diverted by circumstances of minor importance. Whatever actions these circumstances may require, are performed through the force originating in the spinal cord.

The phenomena of reverie are similar in some respects to those of somnambulism. In this condition the mind pursues a train of reasoning often of the most fanciful character, but yet so abstract and intense, that though actions may be performed by the body, they have no relation with the current of thought, but are essentially automatic, and made in obedience to sensorial impressions which are not perceived by the brain. Thus a person in a state of reverie will answer questions, obey commands involving a good deal of muscular action, and perform other complex acts, without disturbing the connection of his ideas. When the state of mental occupation has disappeared, there is no recollection of the acts which may have been performed. Memory resides in the brain and can only take cognizance of those things which make an impression on the mind, or of those ideas which originate in the encephalon.

In the case of a person performing on a piano, and at the same time carrying on a conversation, we have a most striking illustration of the diverse though harmonious action of the brain and spinal cord. Here the mind is engaged with ideas, and the spinal cord directs the manipulations necessary to the proper rendering of the musical composition. A person who is not proficient in the use of this instrument, cannot at the same time play and converse with ease, because the spinal cord has not yet acquired a sufficient degree of automatism, and the mind cannot be divided in its action.

Darwin gives a very striking example of the independent action of the brain and spinal cord. A young lady was playing on the piano a very difficult musical composition, which she performed with great skill and care, though she was observed to be agitated and preoccupied. When she had finished, she burst into tears. She had been intently watching the death-struggles of a favorite bird. Though her brain was thus absorbed, the spinal cord had not been diverted from the office of carrying on the muscular and automatic actions required by her musical performance.

The brain cannot entertain two ideas or initiate two acts at the same time. A person cannot, for example, think of a lamp and a book simultaneously; the thought of the one and the thought of the other will be found to alternate by any one who feels inclined to make the experiment, and not to exist at the same time. Neither can the brain think and simultaneously will. Whatever volitional acts it performs, are distinct from thought, and clearly separated from it by the element of time.

Now in all sleep there is more or less somnambulism, because the brain, according as the sleep is more or less profound, is more or less removed from the sphere of action. If this quiescent state of the brain is accompanied, as it frequently is in nervous and excitable persons, by an exalted condition of the spinal cord, we have the higher order of somnambulic phenomena produced, such as walking and the performance of complex and apparently systematic movements; if the sleep of the brain be somewhat less profound, and the spinal cord less excitable, the somnambulic manifestations do not extend beyond sleep-talking; a still less degree of cerebral inaction and spinal irritability produces simply a restless sleep and a little muttering; and when the sleep is perfectly natural, and the nervous system of the individual well balanced, the movements do not extend beyond changing the position of the head and limbs and turning over in bed.

As regards the power of the spinal cord to supply the nervous force requisite for the performance of such actions as those specified, I do not think there can be any question. Much observation and many experiments have convinced me that the importance of the spinal cord as a center of intellection and volition has been unwarrantably ignored. It is of course not a matter for doubt that the faculty of consciousness is latent in the spinal cord so long as the brain is in a state of activity, and that the faculty of memory does not reside in it at all. When the brain acts, it ordinarily assumes the control of the cord; but there are times, especially during the course of certain diseases, when the latter obtains the mastery over the superior organ and dominates with terrible power.

The actions initiated by the spinal cord are more or less automatic in their character—though not altogether so. The motions of a frog deprived of its brain, show a certain amount of intellection and volition. That they are not more extensive is probably due to the fact that all the organs of the senses, except that of touch, have been removed with the brain. In persons engaged in intense thought and performing actions not in accordance therewith, the impressions made upon the organs of the senses are not appreciated by the brain, but pass through its substance to the spinal cord with which they are in connection by continuity of structure, and which initiates the subsequent actions.

In the somnambulic individual the brain is still more incapable of receiving sensorial impressions. Whatever sense is therefore exercised during the condition of somnambulism, owes its activity to the spinal cord; but in most cases of the state in question, the brain is so profoundly asleep that it does not even transmit impressions to the cord, and hence there are no sensations at all, except that of touch, unless the irritations capable of exciting them are extraordinarily great.

In artificial somnambulism—the hypnotism of Braid—the spinal cord acquires a very high degree of susceptibility to sensorial impressions, and the brain is even more incapable than in natural somnambulism of asserting its superiority. But the consideration of this interesting branch of the subject does not enter into the plan of the present work.

The causes of somnambulism are generally to be found inherent in the organism of the individual, though they may be excited to activity by many circumstances which are capable of exhausting the nervous system or producing emotional disturbance. Young persons are more subject than those of maturer age, and there are few children who do not exhibit at some time or other manifestations of the condition in question, such as muttering and talking in their sleep, laughing, crying, or getting out of bed. Persons of the nervous temperament are those most liable to be affected. In four cases of chorea which have come under my care, the subjects were sleep-walkers in their youth, and the young lady whose case I have related was choreic at the time.

In regard to the treatment there is not much to be said. In the great majority of cases the affection yields readily to appropriate measures; the most efficacious of which consists in means adapted to break up the habit. This may be done by waking the patient before the expected paroxysm, or by placing a tub of cold water so that the feet will be put into it on the attempt to leave the bed. Full exercise in the open air, the avoidance of luxurious habits, and sleeping with the head well raised, are always beneficial.

Of medicines, I have no experience except with the bromide of potassium, and those calculated to improve the tone of the nervous system. The former I have used in two cases with entire success. One of them was that of the young lady, the details of whose case I have related; the other that of a gentleman, forty years of age, who became somnambulic from mental excitement, due to the extensive business operations in which he was engaged. Large doses of this remedy—forty to sixty grains taken at bedtime, and smaller doses, ten to thirty grains, taken twice through the day—broke up the habit entirely in a few weeks. Among the other remedies, I have employed phosphorus, strychnia, and iron with manifest advantage. Cold baths are generally useful. I am acquainted with a young lady who cured herself by taking a cold bath every night just before going to bed. The so-called antispasmodics can scarcely be useful.

Much may be done also by suitable mental training. The reading of exciting fictions, and the witnessing of sensational theatrical exhibitions, are always prejudicial to persons subject to attacks of somnambulism.