imperfect interpretation of natural law. Physical growth and muscular development in man are never completely rounded out, and this may be attributed to a double cause. Theoretically, every muscle of the body should be exercised impartially and be nourished with just the quantity of cell pabulum that is necessary for the replacement of its waste. This never occurs; but it is a possibility that may be contemplated with surety since it is a natural condition. To bring it to pass, reciprocal action must exist between intake and outgo, rebuilding and waste, labor and rest, consciousness and sleep.
The processes of nutrition are involuntary in character so long as material is supplied for their use, but they may be directed by the individual to the extent of the selection and preparation of nourishment. In this they differ from the functions of the involuntary muscles and organs of the body, the control of which is entirely beyond that of the human will. When through abuse the digestive function becomes impaired, disease results. Functional disease is then analogous to muscular fatigue, and, since nature knows but one law of recuperation that of rest it is reasonable to assume what the text
