the skin also can be trained and its powers developed, or it can be allowed to become weak and powerless. Soundness of the skin is as essential to health as soundness of any other organ. A rosy color indicates good health because of a well-balanced circulation. Paleness often means internal congestion and great liability to indigestion, colds, etc. Hence we think a rosy skin beautiful and a pale skin ugly. With the skin in a healthy condition, the danger of taking most diseases is removed.
Characteristics of a Vigorous Skin.—A person who readily takes cold, who is fearful of drafts of air at all times, has a weak skin. To one who has a healthy skin drafts are dangerous only when the skin is moist with perspiration, and the body is inactive; cold drafts may then do harm. Cold air and cold water are the best means of toughening a tender skin. A bath is to the skin what gymnastic exercises are to the muscles. The muscle fibers in the walls of the blood vessels and the nerves controlling them need exercise as well as the rest of the body (Fig. 25).
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Fig. 25.—Blood Vessels, with the Vaso-motor Nerves which accompany and control them.
Importance of Bathing.—If we followed the outdoor life and wore the scanty clothing of savage races, the rains, the cool air, and the sunlight would keep our skins vigorous and sound. But want of exercise to induce perspiration allows the sweat glands to become stopped up. The wearing of clothes is a very uncleanly custom. Clothes make the skin inactive, yet confine the impurities which the weakened skin may still be able to excrete. Thick and
