In this paper, by dreams is meant the visions which occur in natural sleep; by nightmare, a dream unusually intense, involving a terrifying sense of danger and a physical condition to be more fully described ; and by somnambulism, talking, walking, or performing other actions under the influence of a dream attending natural sleep.

Dreams are frequently spoken of, and in almost every possible aspect, by the oldest books of the world. In the Bible, God speaks in a dream to Jacob of the increase of the cattle, and warns Laban not to obstruct Jacob's departure. The dreams of Joseph, unsurpassed in description from a literary point of view, and of Pharaoh, with a history of their fulfilment, occupy a large part of the first book. The dream of Solomon and the dreams of Nebuchadnezzar, the warning of Joseph to take the young Child into Egypt, are parts of the history of the Christian religion. These, being attributed to supernatural influence, can reflect no light upon ordinary phenomena.

But the Bible distinguishes between natural dreams and such as these. It states very clearly the characteristics of dreams. The hypocrite "shall fly away as a dream, and shall not be found: yea, he shall be chased away as a vision of the night." David says, "As a dream when one awaketh," the Lord shall despise the image of the proud. Solomon speaks of the character of dreams thus: "For in the multitude of dreams and many words there are also divers vanities"; of their general causes he says, " For a dream cometh through the multitude of business".

Cicero says that men of greatest wisdom among the Romans did not think it beneath them to heed the warnings of important dreams, and affirms that in his time the senate ordered Lucius Junius to erect a temple to Juno Sospita, in compliance with a dream of Cecilia. Scipio's dream, philosophical, imaginative, grand, published in the works of Cicero, called the most beautiful composition of the kind, has from its origin until now been the subject of discussion as to whether it was written by Cicero for a purpose or is the veritable account of a dream.

Almost all the famous characters described by Herodotus believed that dreams are of supernatural origin. Kings resigned their scepters; Cambyses assassinated his brother; priests attained greatness as commanders; cities which had been destroyed were restored by men who changed their plans and performed these acts because warned, as they supposed, in dreams; and with the invasion of Greece by Xerxes such night visions had much to do. Plato and Socrates believed in dreams, and even Aristotle admitted that they might have a supernatural origin.

There are those who affirm that they have never dreamed. It is obvious that they can testify only that they have never remembered a dream. Their evidence is therefore untrustworthy as to the fact of dreaming; for it is known that recollections of dreams, as a general rule, are very imperfect. Countless details have fled away; the scenes have been inextricably interwoven. A dreamer may be confident that he has dreamed hundreds of dreams, during any given night, yet not be able to recall with distinctness more than one or two. Besides, observation of some who declare that they never dream has demonstrated the contrary; for not only have they moved in ways which indicated that they were dreaming, but talked, and even responded to questions.

Upon only one phase of the subject is there substantial agreement among investigators; namely, the general characteristics of dreams. Time and space are annihilated, and all true estimates confounded. As a rule, to which there are occasional exceptions, nothing appears strange, and impressions which would accompany similar events in the waking state arc not made; or, if at all, so slightly as not to produce their customary effects. Identity being often lost, no surprise is produced by a change of sex, age, name, country, or occupation. A young lady dreamed of seeing herself in her coffin, of listening to the observations of the mourners, and was not astonished to find herself dead, nor that, being dead, she could hear. She was not even surprised when the funeral services closed without the coffin-lid being shut down; nor when, in a very short time, she dreamed of being alive and engaged in her usual pursuits.

But the moment we pass beyond general statements of this character, opinions most incongruous and even contradictory are held, and strenuously advocated, by representative writers in every profession. 1

Nightmare is something so terrible that its very name attributes its origin to the devil. The meaning of "mare" is an incubus, as of a spirit which torments persons in sleep, In nightmare the mind is conscious of an impossibility of motion, speech, or respiration, a dreadful pressure across the chest, and an awful vision of impending danger. The victim sometimes realizes his peril, gathers all his forces, struggles vainly, and endeavors to shout for help. At last, by a desperate effort, he succeeds in screaming. If then some friendly touch or voice awakens him, the vision flees, and he is left stertorously breathing, perspiring, and more tired than if he had broken stone or worked in a tread-mill for as many hours as the nightmare lasted minutes. If not aroused, he may be awakened by his own screams; otherwise the incubus may not depart for a period, which, though short in actual time, seems like ages to him.

1 Those who desire to see the opinions of leading writers, ancient and modern, down to the year 1865, and have not time to consult them in their own works, may find in Seafield's " Literature and Curiosities of Dreams" a very extensive collection. This work has been criticized as containing a largo amount of valuable but undigested information. Tho criticism is not just, for it does not profess to have digested, but to present all for the digestion of others. The author expressly declares that he has " foregone such chances of greater credit and importance as would have been open to him if he had seemed to claim the whole as original, by incorporating the several theories and anecdotes with textual commentary of his own".

More recent investigations of great presumptive importance have introduced an immense amount of new matter into tho literature, and considerable into the "curiosities," of dreams, or at least of dream investigations. Also I have found that some of tho passages quoted by Seafield, read in their original setting, or compared with all the authors have said, require important modifications, if taken as expressions of mature opinion.

A young man under the writer's care was subject to attacks so harrowing that it was excruciating to be in the room with him during the paroxysm. Sometimes after he was awakened the terrifying vision would not wholly fade away for three quarters of an hour or more, during which his shrieks, groans, appeals to God, and the expression of unutterable agony upon his face were terrible. In the city of Philadelphia, a lad, having been exceptionally healthy from birth, was attacked with nightmare when fourteen years old. After a few seizures his father slept with him, for the purpose of awakening him should there be occasion. One night the father was startled by the voice of his boy calling in terrified tones, "Pop! Pop! I'm afraid!" He felt the hand of his son nervously clutching his wrist. Then the boy fainted, and died instantly. The post-mortem examination showed a large clot of blood about the heart, caused by paralysis due to fear. There is reason to believe that such instances are numerous enough to make nightmare worthy of serious medical investigation.

In nightmare, as A. Brierre de Boismont shows, the incubus takes different forms. Sometimes the subject fancies he flies in the air. He gives the case of a distinguished writer, whom he had seen in that state, uttering inarticulate sounds—his hair bristling, his countenance full of terror. At such times he would exclaim, "How surprising! I fly like the wind! I pass over mountains and precipices!" For several seconds after awaking he still imagined himself floating in the air. Others skim over the ground, pursued or threatened by dangers.

In childhood and youth, according to the same author, the individual is upon the edge of precipices, about to fall. In later years, robbers are breaking into the house, or the victim supposes himself condemned to death. Occasionally cats, or other animals or monsters, place themselves upon the stomach. "The weight of this imaginary being stifles, while it freezes the blood with horror." While not every case of nightmare is attended with motion or sound, nightmare passes into somnambulism when the victim shrieks or leaps from his bed, or makes any motion.

Somnambulism, in its simplest form, is seen when persons talk in their sleep. They are plainly asleep and dreaming; yet the connection, ordinarily broken, between the physical organs and images passing through the mind is retained or resumed, in whole or in part. It is very common for children to talk in their sleep; also many are liable to mutter if they have overeaten, or are feverish or otherwise ill. Slight movements are frequent. Many who do not fancy that they have ever exhibited the germs of somnambulism groan, cry out, whisper, move the hand, foot, or head, plainly in connection with ideas passing through the mind. From incipient manifestations of no importance somnambulism readies frightful intensity and almost inconceivable complications.

Somnambulists in this country have recently perpetrated murders, killed their own children, carried furniture out of houses, wound up clocks, and ignited conflagrations. A carpenter not long since arose in the night, went into his shop, and began to file a saw; but the noise of the operation awoke him. The extraordinary feats of somnambulists in ascending to the roofs of houses, threading dangerous places, and doing many other things which they could not have done while awake, have often been described, and in many cases made the subject of close investigation. Formerly it was believed that if they were not awakened they would in process of time return to their beds, and that there would not be any danger of serious accident happening to them. This was long since proved false. Many have fallen out of windows and been killed; and though some have skirted the brink of danger safely, the number of accidents to sleep-walking persons is great.

Essays have been written by somnambulists. A young lady, anxious about a prize for which she was to compete, involving the writing of a composition, arose from her bed in sleep and wrote about a subject upon which she had not intended to write when awake; and this paper secured the prize. The same person, later in life, while asleep selected an obnoxious document from among several, put it in a cup, and set fire to it, and in the morning was entirely unaware of what she had done.

Intellectual work has sometimes been performed in ordinary dreams not attended by somnambulism. The composition of u Kubla Khan" by Coleridge while asleep, and of the " Devil's Sonata" by Tartini, are paralleled in a small way frequently. Public speakers often dream out discourses: there is a clergyman who, many years ago, dreamed that he preached a powerful sermon upon a certain topic, and delivered that identical discourse the following Sunday with great effect. Such compositions arc not somnambulistic unless accompanied by outward action at the time of dreaming them.