[105] De Rochas describes the phenomenon as 'a property of the human organism, more or less developed in different individuals, when the soul, disengaging itself from the bonds of the body, enters the domain, still so mysterious, of dreams' (L'Intermédiaire des Chercheurs et des Curieux, May 10, 1906). In subsequent numbers of the Intermédiaire various correspondents describe their own experiences of such dreams. In Luce e Ombra for June 1906, and in the Echo du Merveilleux for the same date, neither of which I have seen, are given other experiences.
[106] Annals of Psychical Research, November 1896.
[107] Horace Hutchinson, Dreams and their Meanings, p. 76.
[108] American Journal of Psychology, July-October 1903, p. 14.
[109] 'The wish to be able to fly,' he declares (Eine Kindheitserinnerung des Leonardo da Vinci, p. 59), 'signifies in dreaming nothing else but the desire to be capable of sexual activities. It is a wish of early childhood.'
[110] Stanley Hall, American Journal of Psychology, January 1879, p. 158; also F. E. Bolton, 'Hydro-Psychoses,' ib., January 1899, p. 183; as regards rudimentary gill-slits, Bland Sutton, Evolution and Disease, pp. 48 et seq. Lafcadio Hearn travels still further along this road in search for an explanation of dreams of flight, and evokes a 'memory of vanished planets with fainter powers of gravitation,' but he fails to state when the ancestors of man inhabited these problematical planets.
[111] I retain this statement of my explanation in almost the same words as first written down in 1895. I was not then aware that several psychologists had offered very similar explanations. Scherner (Das Leben des Traumes, 1861) seems to have been the first to connect the lungs with dreams of flying, though he put forward the explanation in too fanciful a form and failed to realise that other factors, notably a change in skin pressure, are also involved. Strümpell at a later date recognised this explanation, as well as Wundt.
[112] It is the same with chloroform. 'There are marked sensations in the vicinity of the heart,' says Elmer Jones ('The Waning of Consciousness under Chloroform,' Psychological Review, January 1909). 'The musculature of that organ seems thoroughly stimulated, and the contractions become violent and accelerated. The palpitations are as strong as would be experienced at the close of some violent bodily exertion.' It is significant, also, as bearing on the interpretation of the dream of flying, that under chloroform 'all movements made appeared to be much longer than they actually were. A slight movement of the tongue appeared to be magnified at least ten times. Clinching the fingers and opening them again produced the feeling of their moving through a space of several feet.'
[113] See e.g. Marie de Manacéïne, Sleep, p. 7.
[114] Horace Hutchinson, who in his Dreams and their Meanings (1901), has independently suggested that 'this flying dream is caused by some action of the breathing organs,' mentions the significant fact (p. 128) that the idea of filling the lungs as a help in levitation occurs in the flying dreams of many persons.