upbuilding and waste. Mastication, which is the mechanical part of ingestion, must, of course, be correctly accomplished to insure this result. Hunger is discriminative and preserves the body. Appetite is abnormal desire and ultimately destroys. Hunger is primarily indicated in the mouth, and, if not relieved, becomes an organic craving that can be satisfied only by digestible food; but appetite is silenced when even indigestible substances are ingested.
After the fast, with the return of normal hunger, the food selective sensations of taste and smell are also restored. These faculties in average existence are trained to accept material and odor abhorrent to naturally constituted organisms; but in normal state, while dependent upon true hunger, they act as minor indicators in determining the point that marks the conclusion of the fast. And with them thirst appears not that desire for liquid produced by stimulation or by drug-exhaustion of the fluids of the body, but that which makes known the immediate need for their renewal. The body that eats when hunger, not appetite, calls, that drinks when thirst, not stimulation, demands, and that follows unquestioningly the selective
