ADDITIONAL REMARKS
At the date of going to press we have not received answers sufficient in number to warrant very definite statements in regard to sleep and dreams. A thorough report must be reserved for a later edition. Nor was the time sufficient for the very considerable labor of examining and tabulating the replies. It appears, however, that about one person in thirty regards himself as a poor sleeper, and only two others in thirty will say they sleep only fairly well. About three persons out of five report that they spend no time in wakefulness in bed; the remaining two persons spend from fifteen minutes to five or six hours each, the average among this group being one hour and ten minutes per person per night. Among professors in our leading universities the prevailing hour for retiring is between 10 and 11 o’clock; four-fifths of this group say they retire either at 10, 10.30, or 11 o’clock; but this class of people retire on the average about one-half hour later than persons of the other classes from whom we have received replies.
The average duration of sleep is, roughly, seven and one-half hours. One-third of all replies gave eight hours as the length of sleep; and the professors are inclined to sleep a slightly longer period than those in the other occupations taken together.
The age of the individuals seemed to have no effect on the averages of the daily amount of time spent in sleep. Persons under the age of forty differed in no marked degree from persons over forty either in length of sleep or frequency of dreaming. There is general agreement on the point that they get just enough sleep, and that vacations make only a slight increase. The data is not yet sufficient to justify a conclusion as to the average time of sleep at different ages.
In reference to dreams, about 15 per cent. report that they do not dream, and about 30 per cent. say they dream “rarely,” “seldom,” or “occasionally.” We are disposed to question these returns on the ground that they give an impression that dreams are less frequent than they really are. The investigations of most experimenters who have made special studies of dreams seem rather to show that the number of our dream-experiences grows as soon as we give our attention to them, just as, on a clear night, a hasty glance at the sky may reveal many stars, but a steady gaze reveals very many more.
Our returns are interesting as to the character of the dreams. The favorite adjective used to describe dreams was “rational.” A lesser number of persons said their dreams were “pleasant,” less still that they were “fantastic.” Three times as many persons describe their dreams as pleasant than those who describe them as generally unpleasant. Either Professor Freud’s conclusion is correct, that we tend to forget unpleasant experiences more readily than pleasant ones, or else the dreams really afforded more pleasurable than they did disagreeable feelings. The most typical combination used to describe the nature of the individual’s dream-life was that it was “rational and pleasant.” Less than one-third of all the answerers confessed to having ever experienced nightmare.
It should be observed that thus far we have encountered a group of replies from persons who, as a group, are remarkably healthy, normal, and fairly free from worry. Particularly, worry does not seem to be a vice of professors, as only 8 per cent. confess to it. About 17 per cent. of them say they need more physical exercise than they get, which is mostly walking. There is also a gratifying unanimity as to good appetite, simple diet, and absence of need for artificial means of inducing sleep.
APPENDIX E
BIBLIOGRAPHY
It is surprising how little has been written about Sleep, and what a small part of what has been written is worth reading. Perhaps the best book, certainly the most exhaustive, is Marie Manacéïne’s “Sleep,” which contains a full but disorderly Bibliography.
Except in the case of American works, which might easily have escaped Marie Manacéïne’s attention, I have not tried to go further back than that Bibliography, as she was most industrious in research; I have only cut out from her list what seemed the more obsolete or needless works. But with the help of A. T. Craig and others, I have carried it, as far as may be, down to date.
Bibliography Selected from that Given in “Sleep” (Manacéïne).
Abercrombie: Inquiries Concerning the Intellectual Powers, p. 283 et seq., 1840.
Baillarger: De l’influence de l’état intermédiare à la veille et au sommeil sur la production et la marche des hallucinations. Annales Médico-psychologiques, 1845, tome vi.
Bichat: Sur la Mort et la Vie. Paris.
Brierre de Boismont: Etude médico-légales sur les hallucinations et les illusions. Annales d’hygiène publique et de médicin légale, 1861, tome xvi.
Broadbent: Insomnia, Lancet, April, 1887.
Burnham, W. H.: Memory, Historically and Experimentally Considered. Part III, Paramnesia, Amer. Jour. of Psychol., May, 1889.
Byford: On the Physiology of Exercise. Amer. Jour. of the Med. Sciences, 1855, No. 59.
On the Physiology of Repose or Sleep. Amer. Jour. of the Med. Sciences, April, 1856.
Catlin: Shut Your Mouth, 1870.
Condillac: Essai sur l’origine des connaisances humaines, Sect. I, chapter ix.
Crichton-Browne, J.: Dreamy Mental States. Lancet, 1895, No. 3749.
Delboeuf: Le Sommeil et les Rêves.
De Sanctis and Neyroz: Experimental Investigations Concerning the Depth of Sleep. Psychol. Rev., vol. ix, pp. 254-282. 1902.
Dufay: La notion de la personalité.
Durham: The Physiology of Sleep.
Guy’s Hospital Reports, vol. vi, 1860.
Psychol. Jour., vol. v, p. 74 et seq.
Errera, Leo: Sur le Mécanisme du Sommeil. Brussels, 1895.
Fazio: Sul Sonno naturale, studio teoretico sperimentale, Il Morgagni, 1874.
Frölich: Ueber den Schlaf, Berlin, 1799.
Fucker: Light of Nature Pursued, 1805, vol. i.
Greenwood, Fred: Imagination in Dreams, and their Study, 1894.
Hammond: On Wakefulness, 1866, 1873.
Sleep and Its Derangements.
A Treatise on Insanity, p. 115 et seq. Philadelphia, 1869.
Hartmann: Philosophy of the Unconscious.
Henne: Du Sommeil Naturel.
Herbart: Sämtliche Werke, Bd. V., p. 541 et seq.
Howell: A Contribution to the Theory of Sleep, Jour. of Exper. Med., 1897.
Judée: De l’état de rêve. Gazette des Hôspitaux, 1856.
Lange: Geschichte des Materialismus, 1875. (English trans. by E. C. Thomas, 1881.)
Lemoine: Du sommeil au point de vue physiologique et psychologique, 1855.
Liébault: Du sommeil et des états analogues, 1866.
Maudesley: Body and Will, 1883.
Meyer, Bruno: Aus der Æsthetischen Pädagogik.
Moore, C. A.: On Going to Sleep, 1871.
Nagel: Der natürliche und künstliche Schlaf, 1872.
Nudow: Versuch einer Theorie des Schlafes, Königsberg, 1791, p. 129 et seq.
Patrick and Gilbert: On the Effects of Loss of Sleep, Psych. Rev., Sept., 1896.
Paulhan, A.: De l’activité de l’esprit dans le rêve, Revue Philos., Nov., 1894, p. 546.
Plattner: Von dem Schlaf der Kinder, welcher durch das Einwiegen hervorgebracht wird (1740).
Pierrot: De l’insomnie, 1869.
Radestock: Schlaf und Traum, 1879.
(In Rev. Philos.), April, 1897: La rapidite de la pensée dans le rêve.
Le sommeil et la cérébration inconsciente.
Sanctis, Sante de: I Sogni e il Sonno; I Sogni nei Deliquenti, Archivio di Psichiatria, 1896, vol. vi.
Emozioni e Sogni. Dritter Internationale Congress C Psychol., Munich, 1897, p. 348.
Scherner: Das Leben des Traumes, 1861.
Schubert: Geschichte der Seele, p. 420 et seq.
Serguéjeff: Physiol. de la Veille et du Sommeil, t. i. and ii., 1890.
Siebeck: Das Traumleben der Seele.
Stewart, Dugald: Handbook of the Philosophy of the Human Mind.
Strümpell: Die Natur und Entstehung der Träume.
Sully, J.: The Human Mind, vol. ii.
Illusions, International Scientific Series.
Dream, (Article) Encyclop. Brit.
The Dream as a Revelation, Fortnightly Rev., March, 1893.
Symonds, J. A.: Sleep and Dreams, 1851.
Tarchanoff: Observations sur le sommeil normal. Atti dell’ XI Congresso Med., Roma, 1894, vol. ii.
Verity: Subject and Object as Connected with our Double Brain, 1872.
Volkelt: Die Traum-Phantasie, 1875.
Walsh: On Sleep, Lancet, 1846, vol. ii., p. 181.
Weygandt: Entstehung der Träume, 1893.
Wigan, A. L.: The Duality of Mind, 1844.
Wilks, Samuel: On the Nature of Dreams, Med. Mag., Feb., 1894.
On Overwork, The Lancet, June 26, 1875.