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rest in any way; be idle; inattentive; live thoughtlessly; be dead: the noun substantive and all the derivatives follow these senses.

If the man be poor, thou shalt not sleep with his pledge. Deuteronomy.

If we believe that Jesus died and rose again, even so them also which sleep in Jesus will God bring

with him.

1 Thess. Methought I heard a voice cry, Sleep no more! Macbeth doth murder sleep; the innocent sleep ; Sleep, that knits up the ravelled sleeve of care; The birth of each day's life, sore labour's bath, Balm of hurt minds, great nature's second course, Chief nourisher in life's feast.

Shakspeare. Macbeth. Steel, if thou turn thine edge, or cut not out the burley-boned clown in chines of beef ere thou sleep in thy sheath, I beseech Jove on my knees thou mayest be turned into hobnails. Id. Henry VI. How sweet the moonlight sleeps upon this bank! Here will we sit, and let the sounds of musick Creep in our ears. Id. Merchant of Venice. Heaven will one day open The king's eyes, that so long have slept upon This noble bad man. Id. Henry VIII.

You ever

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Why did you bring these daggers from the place? They must lie there. Go, carry them, and smear The sleepy grooms with blood.

Id. I rather chuse to endure the wounds of those darts which envy casteth at novelty, than to go on safely and sleepily in the easy ways of ancient mistakings. Raleigh.

Cold calleth the spirits to succour, and therefore they cannot so well close and go together in the head, which is ever requisite to sleep. And, for the same cause, pain and noise hinder sleep; and darkness furthereth sleep. Bacon.

Let penal laws, if they have been sleepers of long, or if grown unfit for the present time, be by wise judges confined in the execution.

That sleepe might sweetly seale His restfull eyes, he entered, and in his bed In silence took.

Peace, good reader! do not weep; Peace, the lovers are asleep:

They, sweet turtles! folded lie

In the last knot that love could tie.

Let them sleep, let them sleep on,
Till this stormy night be gone,
And the eternal morrow dawn;

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Id.

Chapman.

Crashaw.

Let such bethink them, if the sleepy drench Of that forgetful lake benumb not still.

The field

To labour calls us, now with sweat imposed, Though after sleepless night.

Milton.

Id. Paradise Lost.

The giddy ship, betwixt the winds and tides Forced back and forwards, in a circle rides, Stunned with the different blows; then shoots

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Infants spend the greatest part of their time in sleep, and are seldom awake but when hunger calls for the teat, or some pain forces the mind to perceive Locke. Those who at any time sleep without dreaming, can never be convinced that their thoughts are for four hours busy without their knowing it. Id.

He must be no great eater, drinker, nor sleeper, that will discipline his senses, and exert his mind; every worthy undertaking requires both.

Grew.

A person is said to be dead to us, because we cannot raise from the grave; though he only sleeps unto God, who can raise from the chamber of death. Ayliffe's Parergon.

We sleep over our happiness, and want to be roused into a quick thankful sense of it. Atterbury. He would make us believe that Luther in these actions pretended to authority, forgetting what he had sleepily owned before. Id. Watchfulness precedes too great sleepiness, and is the most ill-boding symptoms of a fever.

Arbuthnot.

While pensive poets painful vigils keep, Sleepless themselves to give their readers sleep.

Pope.

Silence; coeval with eternity, Thou wert ere nature first began to be, 'Twas one vast nothing all, and all slept fast in thee. Id.

I sleeped about eight hours, and no wonder, for the physicians had mingled a sleepy potion in the wine. Gulliver.

SLEEP, in physiology, is that state of the body in which, though the vital functions continue, the senses are not affected by the ordinary impressions of external objects. See DREAMS, MEDICINE, Index, and PHYSIOLOGY.

'General sleep,' says Bichat, is the assemblage of particular sleeps. It is derived from that law of the animal life which causes in its functions a constant succession of periods of activity, and times of intermission; a law which pointedly distinguishes it from the organic life. Hence sleep influences the latter only in an indirect way, while it exerts its full operation on the former. There is something very just and original, as it seems to us, in this notion, we therefore continue our extract.

'Numerous varieties may be remarked in this periodic state, to which all animals are exposed. The most complete sleep is that in which the whole external life, that is, the senses, perception, imagination, memory, judgment, locomotion, and the voice, are suspended; the least perfect affects only a single organ. We see numerous gradations between these two extremes; sometimes the senses, perception, locomotion, and the voice, are suspended; imagination, memory, and judgment remaining active; sometimes locomotion and the voice are added to the latter. Such is the sleep which is agitated by dreams. A portion of the animal life still continues active, having escaped the torpidity in which the rest is plunged. Three or four senses

only may have passed into the state of repose, and ceased to be influenced by external objects; then that kind of somnambulism occurs in which to the action of the brain, the muscles, and the larynx, are added those of hearing and touch, often in a very distinct form.

'Let us then no longer regard sleep as a constant state, invariable in its phenomena. Scarcely do we sleep twice together in the same way; a multitude of causes modifies this condition of our being, by applying to a greater or smaller portion of the animal life the general law of intermittent action. The various modifications must be characterised by the functions, which are affected in different instances. The principle is the same throughout, from the simple relaxation, which follows the contraction of a voluntary muscle, to the entire suspension of the animal life. Sleep is in all cases a consequence of that general law of intermission which exclusively characterises this life, but the application of which to the various external functions varies infinitely. This explanation of sleep is undoubtedly very different from those narrow systems which place its cause in the brain, the heart, the large vessels, the stomach, &c., and thus present an insulated phenomenon, often illusory, as the basis of one of the great modifications of life.

Why do light and darkness, in the natural order of things, correspond respectively to the activity and repose of the external functions? Because, during the day, the animal is surrounded with a multitude of exciting causes; a thousand things exhaust the powers of the sentient and locomotive organs, fatigue them, and thus prepare a relaxation, which is favored at night by the absence of all stimuli. Thus, in the modern way of life, in which this order is partly inverted, we assemble round us, during the night, various stimuli, which prolong the state of watchfulness, and make the intermission of the animal life coincide with the first hours of the dawn, favoring it by removing all circumstances that might produce sensations. By multiplying around them causes of excitation, we can, for a certain time, prevent the organs of the animal life from obeying the law of intermission; but they yield at last, and nothing, after a certain time, can suspend its influence. Exhausted, by continued exertion, the soldier sleeps at the side of the cannon, and the criminal even amid the tortures of the question.

Let us, however, distinguish natural sleep, the consequence of fatigue of the organs, from that which is caused by affections of the brain, as apoplexy, or concussion. In the latter case the senses are awake, they receive impressions, and are affected by them as usual; but these impressions cannot be perceived by the disordered brain, and we, consequently, are not conscious of them. In sleep, on the contrary, the intermission of action affects the senses as much, and even more than the brain.'-Recherches Physiol. sur la Vie et la Mort, p. 34-37.

Sound sleep is much less common than that which is interrupted by dreams, in which a series of sensations, perceptions, and reflections, passes

through the mind, as in the waking state. We are conscious of the same kind of transactions as occupy our waking hours; we see, hear, walk, talk, and perform all the customary offices of life. The mind reasons, judges, performs volition, and experiences the various affections, as love, hatred, indignation, anxiety, fear, joy, even in a much more lively degree, than when they are excited by their real causes. In dreaming, as in the soundest sleep, the action of the external senses is suspended; but the internal faculties are active in greater or less number. Volition takes place, but the muscles do not obey the will. That dreaming is a less sound species of sleep appears from the familiar fact, which has probably been observed by every individual; viz. that the first sleep is much freer from it than the second. We retire to rest, fatigued by the exertions of the day, and sleep soundly for five or six hours; we wake, and then fall asleep again towards the morning, and dream the whole time of this second sleep. Haller, who mentions that he had attended much to his dreams, observes, that in perfect health he remembered only the sensation of flying through the air, conceiving himself suspended above the earth and carried to a distance.

The order of the images and reflections, which pass through our minds in sleep, and the laws of their succession and connexions, are the same as when we are awake. We must observe, however, that these internal processes now go on by themselves, and are not corrected by that reference to external objects, and that exercise of the external senses, which takes place in the waking state. Thus we see a friend long dead, without being aware that he is not alive; and gross inconsistencies and absurdities take place without being remarked. The great activity of the imagination and judgment, in the act of dreaming, is evident from the nature of many dreams. ten,' says Haller, 'in my dreams, I seem to read books, printed poems, histories of travels, &c.; and I even see the plants of distant regions, suited to their climates.' Others solve problems, write, make verses, &c. The reasonings which are carried on in sleep, the speeches which are made, &c., are often more quickly and easily performed than when we are awake. See DREAMS.

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Some horses sleep standing; and the lowe. jaw is maintained elevated in us during sleep. The hand is often raised when any stimulus is applied to the body, although it may not be strong enough to interrupt sleep. The fact of children expelling their urine, when the pot is brought to them, has been already noticed. Many persons laugh, weep, sigh, and talk in their sleep: the words are indeed generally indistinctly pronounced, and the sentences incomplete.

Somnambulism differs from these only in degree. The sleep-walker executes the voluntary motions, which arise out of the mental processes carried on in sleep. It would be endless to recount the particular cases belonging to this subject. It is sufficient to mention that individuals rise from bed asleep, and with their eyes

closed, and not only walk about the room or house, going up or down stairs, finding their way readily, and avoiding obstacles, but pass safely through very dangerous places, as windows, or on the roofs of houses. They execute, too, still more difficult feats. They dress themselves, go out of doors, light a fire, undress and bathe, saddle and bridle a horse, ride, write, make verses, and execute all the actions of life correctly, and even sometimes acutely. During this time they are asleep; the eyes are shut, or do not see if open; the iris is not irritable. When awakened, which is sometimes not easily effected, they do not remember what they have done.

The proportion of time passed in sleep differs in different individuals, and at different ages. From six to nine hours may be reckoned about the average proportion. Men of active minds, whose attention is engaged in a series of interesting employments, sleep much less than the listless and indolent; and the same individual will spend fewer hours in this way, when strongly interested in any pursuit, than when the stream of life is gentle and undisturbed. The great Frederic of Prussia, and John Hunter, who devoted every moment of their time to the most active employments of body and mind, generally took only four or five hours sleep. A rich and lazy citizen, whose life is merely a chronicle of breakfasts, dinners, suppers, and sleep, will slumber away ten or twelve hours daily. When any subject strongly occupies us, it keeps us awake in spite of ourselves. These phenomena are consistent with what we have already said; the animal organs, when the period of their intermission and repose has arrived, are kept in activity by new and unusual causes of excitation, and thus the ordinary period of sleep may be passed over, and its ordinary quantity much diminished. When a person, who has thus been kept long awake by the occupation of his mind with important and urgent subjects, at last falls asleep, the slightest irritation calls up in the fancy all the trains of thought which have just occupied us, and sets at work again all the internal machinery which has hardly yet become quiet; the sleep, under such circumstances, is imperfect, and much disturbed by dreaming.

The ordinary period of sleep may be protracted by unusual excitation; but the effect is lost after a certain time, and sleep comes on under circumstances which appear at first most unfavorable to it. An eye-witness reports, that some boys, completely exhausted by exertion, fell asleep amid all the tumult of the battle of the Nile; and other instances are known of soldiers sleeping amid discharges of artillery, and all the tumult of war. Couriers are known to sleep on horseback, and coachmen on their coaches. A gentleman, who saw the fact, reported to the writer of this article that many soldiers, in the retreat of Sir John Moore, fell asleep on the march, and continued walking on. Even stripes and tortures cannot keep off sleep beyond a certain time; but it then indicates the greatest exhaustion, and consequently affords an unfavorable prognosis. Noises at first prevent us from sleeping, but their influence soon ceases, and VOL. XX.

persons rest soundly in the most noisy situations. The proprietor of some vast iron-works, who slept close to them, through the incessant din of hammers, forges, and blast-furnaces, would awake if there was any interruption during the night: and a miller, being very ill and unable to sleep, when his mill was stopped on this account, rested well and recovered quickly when the mill was set a going again.

Hunger will prevent sleep; and cold affecting a part of the body has the same effect. These causes operated on the unfortunate women who lived thirty-four days in a small room overwhelmed by snow, and with the slightest sustenance: they hardly slept the whole time. (Somis Ragionamento sopra un fatto avvenuto in Bergemoletto, &c., p. 74.) Indigestion also, and various bodily affections, produce sleeplessness.

One of the latest theories that has appeared upon this subject has been offered to the world by the late Dr. Mason Good in a note appended to his translation of Lucretius, b. iv. v. 936, and on this occasion, as well as on account of what we believe to be its perfectly satisfactory result, we are glad in having an opportunity of presenting it to our readers: the more especially as it undertakes to unfold the very obscure and hitherto perplexing doctrine of dreaming. It is offered to us for the sake of conciseness under the following lemmata:

I. All the fibrils of the nervous system become fatigued, exhausted, and torpid, in proportion to the length and violence of their exertion, and recover their power alone by rest. The weariness and debility of the muscles of the arms and legs, after extreme exercise, or exercise to which they have not been accustomed, may be adduced as a sufficient proof of this position. The nervous fibrils of the external organs of sense are necessarily subject to the same effect; we neither hear, nor see, nor taste, nor feel, with the same accuracy, after any or all these various organs have been long upon the full stretch of action, with which we do on their first exertion in the morning. Increase or prolongate their action, and their power will be still farther obtunded, till at length, like an over-wearied limb, they become perfectly lethargic, and give no account of whatever is occurring around us; and it is this uniform lethargy, torpidity, or inaction of all the external senses, which we denominate sleep. By the exercise of the will, or any other strong stimulus, this sleep, or sensorial torpidity, may be postponed: and vice versâ, by the consent of the will, it may be expedited.

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II. The vital organs are far less subject to the influence of stimulants of every kind than the organs of external sense: their actions are hence far more equable and permanent; they are seldom wearied or exhausted, and, of course, seldom sleep or become torpid. From the application of very strong stimulants, however, whether external as those of severe pain or labor, or internal, as those of disease or excessive grief, such fatigue or exhaustion actually takes place; and when the exhaustion is complete, they also, like the organs of ex ernal sense, sleep or become torpid: in other words, death ensues, and the spirit separates from the body. The resemblance

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between death and sleep, therefore, is not less correct, upon the principles of physiology, than it is beautiful among the images of poetry. Sleep is the death or torpidity of the organs of external sense, while the vital functions continue their accustomed actions: death is the sleep or torpidity of the whole.

III. Every organ of the animal frame recovers from its fatigue or torpidity by rest, provided the principle of life, that is to say, the action of the vital organs, continues. Hence the organs of external sense, in a definite period of time, and a period generally proportioned to the degree of their exhaustion, re-acquire their accustomed vigor, are alive to the influence of their appropriate stimulants, and the smallest excitement applied to any one of them, throws the whole once more into action: in other words the man awakes from sleep, he rouses himself from the temporary death of the organs of external sense. Were it possible for life to continue during a total rest or torpidity of the vital organs, as it does during that of the organs of external sense, there is no doubt that these also would, in time, recover from their exhaustion, and that the man would, in like manner, awake from the total torpidity, the sleep or death of the entire frame but this is impossible; the soul has now deserted the body: a change in every organ ensues, and the whole system, instead of reviving, becomes a prey to corruption and ruin.

IV. When the organs of external sense have recruited themselves by repose, the stimulus that rouses the one, rouses, at the same time, the rest, from the habit of association. From the same habit the torpidity produced by exhaustion, in any single organ, is propagated through every other, and the sleep becomes common to the whole: although it is also unquestionable that the whole are also fatigued, or partially exhausted, from the fact that the general stock of sensorial power has been borrowed, in a considerable degree, from the rest, and expended at a single outlet.

V. The nervous fibrils, or rather tubules of the external organs of sense, are equally affected, and of course become equally exhausted, whether the stimulus be applied at either end; to wit, the end terminating externally, or that connected with the brain; and hence, internal excitements, as those of severe study, intense grief, undue eating and drinking, or febrile diseases, produce the same effect as causes operating from without.

VI. In either case the sleep or torpidity produced is sound or healthy, under a certain degree of exhaustion alone: hence mankind sleep most refreshingly after moderate or accustomed fatigue, moderate or accustomed study, moderate or accustomed meals.

'VII. If the stimulus be a little increased beyond this medium, the vital organs themselves become affected, an undue and morbid proportion of sensorial power is secreted, which postpones the torpidity or sleep for the present, but at the expense of the general strength of the whole system, which, in consequence, becomes gradually more exhausted and debilitated: whence a far deeper torpidity, or sleep, must necessarily ensue at length, than would have occurred in the first

instance. If such torpidity take place before the vital organs are totally exhausted, it is confined to the external organs of sense alone, which hereby progressively recover their accustomed activity and vigor: if the vital organs be themselves altogether exhausted before the torpidity ensues, it is propagated to themselves, and the consequent sleep is the sleep of death. Violent and long continued labor, as an external stimulus, violent and long continued study, violent and continued fevers, violent and continued grief, a very inordinate debauch, as internal stimuli, are equally liable to produce effects here specified: and the one or the other will take place in proportion to their excess and extremity.

VIII. If the stimulus affecting the external organs of sense, at which end soever it be applied, be intolerably pungent or forcible, the sensorial power is exhausted immediately, and the organ directly affected beomes instantly torpid. Hence sounds, insufferably loud, make us deaf; excessive light makes us blind; acrimonious smells, or savors, render us incapable of smelling or tasting; and hence an abrupt shock of joy or grief, a sudden and intense paroxysm of fever, large quantities of wine or spirits, as internal causes, produce coma, palsy, apoplexy, which are only so many modifications of the sleep or torpidity of the nervous tubules of the external organs of sense. If the same abrupt and violent cause be sufficiently powerful to act upon the vital organs as well as those of external sensation, the torpidity becomes universal, and the sleep induced is once more the sleep of death.

IX. As violent stimulants produce sudden and irrecoverable torpidity, either general or lo cal, according to the mode and place of application, stimulants less violent induce a tendency to the same effect. Hence the nostrils, not accustomed to snuff, are more forcibly agitated by its application than those that are so; the eyes of persons accustomed to sleep in the glare of the sun find no inconvenience from exposure to the light of the morning; while those who always sleep in total darkness are awoke by the return of day-light. And so of the rest.

'X. On this account a very small portion of light, of sound, or of exercise, even the breath of the air alone, are each of them powerful stimulants upon infants, because unaccustomed to them: hence they sleep much and soundly; so soundly, indeed, that no common stimulus is able, for a long time, to arouse them from their torpidity. In other words, it requires a period of many hours for the external organs to recover from their exhaustion. The smallest undulatory motion in the uterus, and the very action of the vital organs themselves, are, perhaps, sufficient to wear out, from time to time, the sensorial power of the fœtus on its first formation: and hence the foetus sleeps, with few intermissions, through the whole period of parturition.

XI. For the same reason persons in an advanced age are far less impressed by common stimulants than in any former period of their lives: from a long series of exposure to their operation their organs are become more torpid, and hence they require less sleep, and, at the same time, less food. The vital organs, as well

as those of external sense, partake of the same disposition. They are, in consequence, less liable to all violent or inflammatory disorders: but, the general torpidity increasing, the heart is stimulated with great difficulty; a smaller portion of sensorial power is secreted from the gases of the atmosphere; a smaller portion of food is thrown into the system from the stomach; the pulse, and every other power, gradually declines, till, at length, if ever man were to die of old age alone, he would die from a total torpidity, or paralysis of the heart. But debilitated or torpified as every organ is become, long before such a period can arrive, the frame at large is incapable of resisting the smallest of those trivial shocks to which man is daily exposed, either internal or external; or, in other words, there is no accumulation of sensorial power to supply the temporary demand, and the man dies from sudden exhaustion rather than from progressive paralysis. Upon this theory I might easily and obviously solve a variety of problems which have hitherto eluded all satisfactory explanation. I shall only add to this outline of the theory of sleep a few observations upon that of dreaming, which is so intimately connected with it, as well in nature as in the poem before us.

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< I. A certain but a very small degree of stimulus applied, perhaps, to any nerve whatever of the human body, instead of exhausting it seems to afford it pleasure; or, at least, the nerve is able to endure it without becoming torpid, or, which is the same thing, requiring sleep or rest. The orbicular motion of the lips, to an infant accustomed to suck, is a source of so much comfort, and attended with so little exhaustion, that, whether sleeping or waking, it will generally be found mimicking the act of sucking, when at a distance from its nurse, and perhaps not thinking of such action itself. A person who, from habit, has acquired a particular motion of any one of his limbs, a twirl of the fingers, or a swinging one leg over the other, perseveres in such motion from habit alone, and feels no torpidity or exhaustion in the nerves that are excited, although it might be intolerably fatiguing to another who has never acquired the same custom.

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II. It is probable that both thought and the action of the vital organs are stimulants of this precise character, if not in their commencement, at least very shortly afterwards: that nearly, if not altogether, from the first they are equally pleasing and gentle in their degree of action; and that hence they equally, also, continue without exhausting us, except when unduly roused; and form a habit too pertinacious and invincible to be broken through by any exertions whatever. Thought is, then, to the brain, that which the inuscular habits I have just spoken of are to the muscles which are the subjects of them. Both continue alike, whether we be reflecting upon the action, or whether we be not: but the habit of thinking is so much older, and, consequently, so much deeper rooted than that of any kind of gesticulation, that, as I have just observed, it is impossible for us to break through it by the utmost efforts of the will: whence it accompanies us, excepting when the brain is totally exhausted, and consequently thrown into a profound tor

pidity or sleep, not only at all times when awake, but almost at all times during sleep, and is the immediate and necessary cause of our dreaming.

III. Thought can only be exercised upon objects introduced into the brain, or general sensorium, by the organs of external sensation; and hence the bent or chief direction of our thoughts, whether sleeping or waking, must be derived from those objects which principally impress us, be the causes of such impression what they may. The train of thoughts, then, which recurs from habit alone, as in sleep or total retirement from the world, must generally be of this description; in the former case, however, by no means correctly or perfectly, because there are others, also, which have a tendency to recur, and neither the will nor the senses are in action to repress them; whence proceeds a combination of thoughts or ideas, sometimes in a small degree incongruous, and at other times most wild and heterogeneous; occasionally, indeed, so fearful and extravagant as to stimulate the senses themselves into a sudden renewal of their functions; and, consequently, to break off abruptly the sleep into which they were thrown.

IV. If the action of the nervous tubules of the brain, thus continued from habit, and producing our dreams, be less powerful during sleep than is sufficient to rouse the senses generally, it may, nevertheless, at times be powerful enough to excite into their accustomed exercise the muscles of those organs or members which are more immediately connected with the train of our dreams, or incoherent thoughts, while, nevertheless, every other organ or member still remains torpid. Hence some persons talk, and others walk in their sleep, without being apprised, on their waking, of any such occurrence.

'V. Whatever be the set of nerves that have chiefly become exhausted from labor or stimulus of the day, the rest, as I have already noticed, partake of the same torpidity from long habit of association; exhausted in some degree, also, themselves by the portion of sensorial power which, as from a common stock, they have contributed towards the support of the debilitated organ. But it sometimes happens, either from disease or peculiarity of constitution, that all the external organs of sense do not associate in their actions, or yield alike to the general torpidity of the frame; and that the auditory, the optical, or some other set of nerves, are in vigor, while all the other nerves of the external senses remain torpid; as it may do also, that an entire organ of external sense, like the muscles of an individual member, as observed in the last paragraph, may be awoke or restimulated into action by the peculiar force and bent of the dream, while alı the rest continue lethargic.

VI. If the organ of external sense thus affected be that of hearing, a phenomenon will occur, which is specifically noted by our poet in book V., v. 1182, but which, I believe, has never hitherto been satisfactorily explained; the dreamer must necessarily hear a bye-stander who speaks to him; and if, from the cause specified above, he should happen to have talked in his sleep, so as to give the bye-stander some clue into the train of thoughts of which his

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