After all, excess in diet is, usually, only another term for lack of fresh air and exercise, without which no one can become, or continue, robust. While it is true that to command health and muscular vigor one must be well fed, still no amount of food alone can make the right arm like that of a blacksmith. But we can make the muscles grow on ample exercise and——food enough; always, however, considering a constant supply of oxygen as an essential element in the ration. The muscular system wastes——with many is never even tolerably developed——the powers wane, because of sedentary habits. “Inaction contravenes the supreme design of the human constitution, and is therefore adverse to its health.”——HUXLEY. The lungs begin to take on disease, often, because the individual does nothing to make him _breathe deep_; exercise is not frequent and vigorous[29] enough to cause frequent deep inspirations; the remote air-cells are in many instances seldom, and with corset-wearers _never_, inflated, and, consequently, the tendency is to grow together, so to say, or, rather, to fester and slough off, as useless appendages. To form the habit of taking long breaths in the open air, occasionally, throughout the day, would do much to maintain the integrity of lung-tissue, aerate the blood and prevent or cure consumption; but, after all, Nature designs that creatures who inhabit this earth shall be “fit” for something besides drawing their own breath.[30] To be “fit to survive” one must be of use in the world; hence there must be employment that taxes the mental, moral, and physical forces sufficiently to stimulate their growth and development. This, and nothing short of this, is health, in the complete sense of the term. _Robust health_, if one would secure it, demands that one should be much in the open air and exposed, often, to a low temperature while taking a great deal of vigorous exercise. To be _long-lived_, on the other hand, requires rather that the diet be restricted to correspond with abstinence from labor and cold, some degree of exercise in the open air, however, being essential. The robust often wear out faster than the brain workers, whose lives are rather on the quiet order. Worry kills ten where work kills one. [Footnote 29: In a badly vitiated atmosphere _inaction_ is the only palliative; muscular exercise causes a demand for an increased supply of oxygen, and increases the amount of carbonic acid to be eliminated, neither of which conditions can be met except by means of pure air.] [Footnote 30: See note 1 in Appendix, p. 275.] The best illustration of the natural means of preventing, or curing, consumption——in fact, of promoting and maintaining health, under any circumstances——I have ever seen, is given in the following true story of HOW A YOUNG GIRL CURED HERSELF.