Dreams of flying are sometimes associated with dreams of falling, the falling sensation occurring either at the beginning or at the end of the dream; such a dream may be said to be of the Icarus type.[116] Jewell considers that the two kinds of dream have the same causation, the difference being merely a difference of apperception. The frequent connection between the two dreams indicates that the causation is allied, but it scarcely seems to be identical. If it were identical, we should scarcely find that while the emotional tone of the dream of flying is usually agreeable, that of the dream of falling is usually disagreeable.[117]

I have no personal experience of the sensation of falling in normal dreaming, although Jewell and Hutchinson have found that it is more common than flying, the latter regarding it, indeed, as the most common kind of dream, the dream of flying coming next in frequency. A friend who has no dreams of flying, but has experienced dreams of falling from his earliest years, tells me that they are always associated with feelings of terror. This suggests an organic cause, and the fact that the sensation of falling may occur in epileptic fits during sleep,[118] seems further to suggest the presence of circulatory and nervous disturbance. It would seem probable that while the same two factors—respiratory and tactile—are operative in both types of dream, they are not of equal force in each. In the dream of flying, respiratory activity is excited, and in response to excitation it works at a high level adequate to the needs of the organism. In the dream of falling it may be that respiratory activity is depressed, while concomitantly, perhaps, the anaesthetic state of the skin is increased. In the first state the abnormal activity of respiration triumphs in consciousness over the accompanying dulness of tactile sensation; in the second state the respiratory breathlessness is less influential than a numbness of the skin unconscious of any external pressure. This difference is rendered possible by the fact that in dreams of flying we are not usually far from the earth, and seem able to touch it lightly at intervals; that is to say that tactile sensitiveness is impaired, but is not entirely absent as it is in a dream of falling.[119]

In my own experience the sensation of falling only occurs in illness or under the influence of drugs, sometimes when sleep seems incomplete, and it is an unpleasant, though not terrifying, sensation. I once experienced it in the most marked and persistent manner after taking a large dose of chlorodyne to subdue pain. Under such circumstances the sensation is probably due to the fact that the morphia in chlorodyne both weakens respiratory action and produces anaesthesia of the peripheral nerves, so that the skin becomes abnormally insensitive to the contact and pressure of the bed, and the sensation of descent is necessarily aroused.[120] It is possible that persons liable to the dream of falling are predisposed to a stage of sleep unconsciousness, in which cutaneous insensibility is marked. It is also possible that there is a contributory element of slight cardiac or respiratory disturbance.[121]

In a dream belonging to this group, I imagined I was being rhythmically swung up and down in the air by a young woman, my feet never touching the ground; and then that I was swinging her similarly. At one time she seemed to be swinging me in too jerky and hurried a manner, and I explained to her that it must be done in a slower and more regular manner, though I was not conscious of the precise words I used. There had been some dyspepsia on the previous day, and on awaking I felt slight discomfort in the region of the heart. The symbolism into which slightly disturbed respiratory or cardiac action is here transformed seems very clear in this dream, because it shows the actual transition from the subjective sensation to the objective imagery of flying. By means of this symbolic imagery we find sleeping consciousness commanding the hurried heart to beat in a more healthy manner.

Although, in youth, my dreams of flying were of what may be considered normal type, after the age of about thirty-five they tended, as illustrated by the example I have given, to take on a somewhat objective form. A further stage in this direction, the swinging movement being transformed to an inanimate object, is illustrated by a dream of comparatively recent date, in which I seemed to see an athlete of the music-hall, a graceful and muscular man, who was manipulating a large elastic ball, making it bound up from the floor. On awaking there was a distinct sensation of cardaic tremor and nervousness.[122]

It may seem strange that dreams of flying, if so often due to organic disturbances, should usually be agreeable in character. It is not, however, necessary to assume that they are caused by serious interference with physiological functions; often, indeed, they may simply be due to the presence of a stage of consciousness in which respiration has become unduly prominent, as it is apt to be in the early stage of nitrous oxide anaesthesia, that is to say, to a relative wakefulness of the respiratory centres. It would seem that the disturbance is frequently almost, or quite, imperceptible on waking, and by no means to be compared with the more acute organic disturbances which result in dreams of murder, although it may be of nervous origin.[123] In some cases, however, it appears that dreams of flying are accompanied by circumstances of terror. Thus a medical correspondent, who describes his health as fairly good, writes in regard to dreams of flying: 'I have often had such dreams, and have wondered if others have them. Mine, however, are not so much dreams of flying, as dreams of being entirely devoid of weight, and of rising and falling at will. A singular feature of these levitation dreams is that they are always accompanied by an intense and agonising fear of an evil presence, a presence that I do not see but seem to feel, and my greatest terror is that I shall see it. The presence is ill-defined, but very real, and it seems to suggest the potentiality of all possible moral, mental, and physical evil. In these dreams it always occurs to me that if this evil presence shall ever become embodied into a something that I could see, the sight of it would be so ineffably horrible as to drive me mad. So vivid has this fear been that on several occasions I have awakened in a cold sweat or a nameless fear that would persist for some minutes after I realised that I had only been dreaming.' This seems to be an abnormal type of the dream of flight.

It is somewhat surprising that while dreams of floating in the air are so common and clearly indicate the respiratory source of the dream, dreams of floating on water seem to be rare, for as the actual experience of floating on water is fairly familiar, we might have expected that sleeping consciousness would have found here rather than in the never experienced idea of floating in air the explanation of its sensations. The dream of floating on water is, however, by no means unknown; thus Rachilde (Mme. Vallette), the French novelist and critic, whose dream life is vivid and remarkable, states that her most agreeable dream is that of floating on the surface of warm and transparent lakes or rivers.[124] One of the correspondents of L'intermédiaire des Chercheurs et des Curieux[125] also states that he has often dreamed of walking on the water.

It is not only in sleep that the sensation of flying is experienced. In hysteria a sense of peculiar lightness of the body, and the idea of the soul's power to fly, may occur incidentally,[126] and may certainly be connected both with the vigilambulism, as Sollier terms the sleep-like tendencies of such cases, and the anaesthetic conditions found in the hysterical. It is noteworthy that Janet found that in an ecstatic person who experienced the sensation of rising in the air there was anaesthesia of the soles of the feet. In such hysterical ecstasy, which has always played so large a part in religious manifestations, it is well known that the sense of rising and floating in the air has often prominently appeared. St. Theresa occasionally felt herself lifted above the ground, and was fearful that this sign of divine favour would attract attention (though we are not told that that was the case), while St. Joseph of Cupertino, Christina the Wonderful, St. Ida of Louvain, with many another saint enshrined in the Acta Sanctorum, were permitted to experience this sensation; and since its reality is as convincing in the ecstatic state as it is in dreams, the saints have often been able to declare, in perfect good faith, that their levitation was real.[127] In all great religious movements among primitive peoples, similar phenomena occur, together with other nervous and hallucinatory manifestations. They occurred, for instance, in the great Russian religious movement which took place among the peasants in the province of Kief during the winter of 1891-2. The leader of the movement, a devout member of the Stundist sect, a man with alcoholic heredity, who had received the revelation that he was saviour of the world, used not only to perceive perfumes so exquisite that they could only, as he was convinced, emanate from the Holy Ghost, but during prayer, together with a feeling of joy, he also had a sensation of bodily lightness and of floating in the air. His followers in many cases had the same experiences, and they delighted in jumping up into the air and shouting. In these cases the reality of the sensory obtuseness of the skin as an element in the manifestations was demonstrated, for Ssikorski, who had an opportunity of investigating these people, found that many of them, when in the ecstatic condition, were completely insensible to pain.

The sensation of flying is one of the earliest to appear in the dreams of childhood.[128] It is sometimes the last sensation at the moment of death. To rise, to fall, to glide away, has often been the last conscious sensation recalled by those who seemed to be dying, but have afterwards been brought back to life. Those rescued from drowning, for instance, have sometimes found that the last conscious sensation was a beatific feeling of being borne upwards. Piéron has also noted this sensation at the moment of death from disease in a number of cases, usually accompanied by a sense of well-being.[129] The cases he describes were mostly tuberculous, and included individuals of both sexes, and of atheistic as well as religious belief. In all, the last sensation to which expression was given was one of flying, of moving upwards. In some death was peaceful, in others painful. In one case a girl died clasping the iron bars of the bed, in horror of being borne upwards. Piéron, no doubt rightly, associates this sensation with the similar sensation of rising and floating common in dreams, and with the feeling of moving upwards and resting on the air experienced by persons in the ecstatic state. In all these cases alike life is being concentrated in the brain and central organs, while the outlying districts of the body are becoming numb and dead.