As you drop off to sleep you can notice the decreased sensation in the long-serving feet which feels as if it slowly climbs to the muscles in the head and neck.
CHAPTER XXIX
STILL MORE THEORIES
Sleep sits upon his brow;
His eye is closed; he sleeps, nor dreams of harm.
Longfellow.
We have not yet exhausted all the theories, nor shown how much too much some of them and how far too little all of them prove.
The two remaining scientific theories of sleep are the psychological and the biological. The best modern exponent of the psychological theory is Marie de Manacéïne, who defines sleep as “the resting-time of consciousness.” Persons whose consciousness is but little developed, young children, and those of weak intellect, usually require a great deal of sleep, while persons whose minds are active, alert, responsive, get along with comparatively little sleep.
For a long time it was believed that living creatures devoid of consciousness would not sleep at all, but recent experiments have apparently weakened that conclusion. Dogs, pigeons, and other animals deprived of brains in the interest of scientific discovery, appear to sleep, that is, they have periods of inactivity, just as those with brains and consciousness. Belmondo, after repeated experiments, drew the conclusion that sleep is not a purely cerebral function, as some believe, but that the whole organism sleeps; and the brain sleeps only because the organs of sense sleep. This, however, is doubtful.