Imagine a music machine so cunningly constructed and adjusted as not only to sound each note and chord in its proper sequence and relation, but to regulate also the duration of the sound vibration.  If this machine were operated in such a manner as to play, in a single second of time, the entire overture of an opera which would normally occupy half an hour, we should hear only an unintelligible noise a second long.  This would be due to no defect in the sound-producing mechanism, but to the limitations of the sound-receiving mechanism, our auditory apparatus.  Could this be altered to conform to the unusual conditions—­could it capture and convey to consciousness every note of the overture in a second of time—­that second would seem to last half an hour, provided that every other criterion for the measurement of duration were denied for the time being.

Now dreams seem long:  we only discover afterwards and by accident their almost incredible brevity.  May we not—­must we not—­infer from this that the body is an organ of many stops and more than one keyboard, and that in sleep it gives forth this richer music.  The theory of a higher-dimensional existence during sleep accounts in part for the great longing for sleep.  “What is it that is much desired by man, but which they know not while possessing?” again asks Leonardo.  “It is sleep,” is his answer.  This longing for sleep is more than a physical longing, and the refreshment it brings is less of the flesh than of the spirit.  It is possible to withstand the deprivation of food and water longer and better than the deprivation of sleep.  Its recuperative power is correspondingly greater.

Experiments have been made with mature University students by which they have been kept awake ninety-six hours.  When the experiments were finished, the young men were allowed to sleep themselves out, until they felt they were thoroughly rested.  All awoke from a long sleep completely refreshed, but the one who took longest to restore himself from his protracted vigil slept only one-third more time than was regular with him.  And this has been the experience over and over again of men in active life who have been obliged to keep awake for long periods by the absolute necessities of the situation in which they have been placed.

In this fact there is surely another hint of the sublimation of the time sense during sleep.  While it would be an unwarrantable assumption to suppose that the period of recuperation by sleep must be as long, or nearly as long, as the period of deprivation, the ratio between the two presents a discrepancy so great that it would seem as though this might be due to an acceleration of the time element of consciousness.

THE EASTERN TEACHING IN REGARD TO SLEEP AND DREAMS