What may be termed the balance of power or just distribution of force in the various parts of our physical and mental nature--according to each individual type--is essential to the perfection of the organization--it is, indeed, the measure of health. It is attained and preserved by the due exercise of all the functions of our nature. In ascertaining what is this due exercise, we observe that the different functions of the human being are subject to varying laws of constant or occasional action. The higher the object of a function, the wider is its scope, the longer are the intervals of rest required, and the more direct is its subjection to reason; it is taken from under the control of the automatic vegetative life of the body and placed under the direction of the central authority--Reason--Conscience. Thus, we see the lungs, whose sole object is the physical life of the individual, breathing day and night unceasingly, with alternate rest and action every moment. The digestive apparatus, with longer intervals of rest and a wider range of objects, connected with the preparation and enjoyment of food. The senses, with their great use both to the individual and to society, locked in slumber every night. Thus, step by step, the plan rises to the highest functions of human nature--those which concern the race--which, above all others, are under the dominion of reason, and not subject to that law of constant action which controls the lower functions. Equally interesting is that law of our nature which determines growth by exercise. It is a fact clearly demonstrated by modern science that the governing organ of the human body, the brain, has distinct portions of its structure devoted to the service of distinct faculties of the mind. Thus the intellectual, the emotional, and the locomotive powers work through corresponding portions of the highly organized brain. Each faculty grows by exercise. Not only does the mental faculty become stronger by use, but its physical organ of expression in the brain, with its dependencies in the rest of the body, become larger and stronger with a richer supply of blood and greater aptitude for instantaneous action. This condition of the physical organ reacts upon the mind, which takes greater pleasure in acting in a certain direction when it finds the brain so keenly responsive to its impulses. If the proper distribution of force is disturbed in any individual by the neglect to exercise important portions of our nature, an antagonism of faculties springs up, one part growing at the expense of another part. Thus the emotional may destroy the intellectual life in an individual who is subjected to undue excitement of the passions, particularly if the type of the nature is not largely emotional. The other faculties will rapidly lose their power. The intellect suffers, judgment is lost, and mental confusion produced, which is really a species of insanity. Those organs of the body, also, which are most intimately