The question of color is an important factor in clothing. This is especially true in summer when exposure to the sun makes it especially necessary to consider our comfort. All dark-colored clothing absorbs the heat and the sun becomes very oppressive to the wearer. Then, too, black and dark-colored coverings shut out the light, another objectionable feature. In my reference to sun baths in the preceding chapter on Blood Purification I placed special emphasis upon the value of light as a vitalizing and stimulating factor in life and health. Ordinarily we not only smother our skins so far as the air is concerned, but we also shut out the light, hiding our bodies in a cellar, so to speak. Our bodies need light as well as air and for this reason dark colored clothing cannot be recommended. For warmth when in the sunshine during the winter, black is very effective. When out of the sunshine black is cooler in winter than light-colored fabrics because it quickly radiates the body heat. It is well known that a black stove radiates the heat much faster than a nickel-plated or brightly polished stove.
White or light-colored garments are advised in summer, both because they are cooler and because they permit the light to reach the skin. The Arabs, Bedouins and others who live in unforested countries where they are much exposed to the tropical sun use turbans and flowing robes of white as a means of keeping cool. Pure white is often unserviceable, because it quickly becomes soiled, and therefore gray and tan- colored garments are recommended.
It is easily possible to absorb too much sunshine, especially in the lower latitudes. The various races of the earth enjoy a degree of pigmentation of the skin corresponding to the intensity of the sunlight in the latitude to which they have become accustomed through the course of evolution. Equatorial races are black, far-northern races are blonde with very fair skin, and those occupying mean latitudes are either brown or olive-hued. Brunettes or fairly dark-complexioned white men can stand more sunshine than the blue-eyed, fair-skinned types of Scotland, Norway and Sweden. Where the latter are exposed to intensely strong sunshine in latitudes further south than their natural home, and especially when visiting the tropics, where the sun's rays are nearly vertical, some special protection from the excessive light is necessary. Then the upper or outer clothing should be white or light-colored, but an undergarment of some opaque or dark-colored material should be used to shut out the light. In the case of tropical animals Nature provides a light-colored or tawny growth of hair, with an underlying black or heavily pigmented skin. The white man when in the tropics or when subject to the chemical rays of the sun in midsummer would do well to follow Nature's example, wearing light clothing outside with black- or orange-colored or other opaque underwear. The hat should be white or tan or light-colored on top, but with a dark-colored lining extending under the brim. Blonde types spending the summer in a latitude like that of Texas or Mexico would do well to consider these suggestions. Sunlight is essential to life. Sun baths are invaluable and ordinarily our clothing should be such as to permit the light to reach the skin. But when the sun's rays are nearly vertical fair-skinned persons may easily protect themselves and maintain comfort by following this suggestion.
As a general thing, during both winter and summer, one should wear no more clothing than necessary, and that should be of a type to permit easy access of air to the skin. For this reason the character of one's underwear is important. Wool is undoubtedly warmer and more or less suitable for exceptionally cold weather; yet for most purposes linen is to be preferred because of its more porous character. Linen permits of free circulation of the air, and when the underwear is woven with an open mesh it is especially satisfactory. Next to linen cotton is to be preferred, being likewise porous. The question of underwear is one to be determined largely by individual taste and requirements, but always it should be understood that one should wear underwear as light as is consistent with warmth and as porous as possible. This principle should also apply in the matter of shoes. Air-tight foot coverings are highly detrimental as well as uncomfortable. Leather in its natural state is porous and therefore a healthful foot covering. Patent- leather shoes, however, have been made air-tight by a special process, and are very hot, uncomfortable and unsanitary. The sole of the shoe should consist of nothing but plain leather. So-called waterproofing processes, making the shoe air-tight as well as waterproof, should be avoided. Patented, waterproof soles are highly objectionable. If you can have your shoes made to order see to it that the sole consists of nothing but leather-indeed a single layer of good sole leather is most satisfactory. Although such shoes will absorb water they will dry readily, and the disadvantage of wet feet on occasions is more than offset by the benefits gained from a porous foot covering the rest of the time. Anyway, wet feet are unimportant if the feet are warm.
A word about winter clothing. Heavy underclothing is entirely unsuited to the temperatures maintained inside our houses during the winter. We usually have a summer temperature indoors in winter and should wear summer clothing. It is true that we require warmer clothing out-of-doors in winter, but this should be used only when out-of-doors; we should not wear heavy, warm garments both indoors and out. Therefore, while the farmer who spends the day in the open would probably need heavy warm underwear, the city man should dress approximately the same as in summer when indoors, and add the garments necessary for additional warmth when going out. Sweaters, gaiters and overcoats should be depended on when going out-of-doors instead of heavy undergarments.
Clothing, as I have said, is a necessary evil. So far as possible it should not hamper our movements and should not deprive our bodies of light and air. Since it is necessary to wear clothing, I would strongly emphasize the importance of taking air baths at frequent intervals. When spending the evening in the privacy of your own room, studying or writing letters, you have a good opportunity to enjoy an air bath during the entire evening. And furthermore, when at home you should lay aside your coat and use no more bodily covering than is necessary. If you cannot take sun baths at a special hour each day, then I would advise that when taking your walk out-of-doors in the sunshine you wear clothing of such a character as to admit the rays of the sun, thus enabling you to enjoy a sun bath during your walk. A special suit of clothes, made of natural-colored linen, with a thin light shirt, light- colored socks and no underwear, would answer all purposes admirably.
[CHAPTER XIX: Suggestions About Sleep]
Sleep is one of the first essentials in maintaining or in building vitality. There are differences of opinion as to how much sleep may be necessary to health, but that sufficient sleep is required if one wishes to maintain the maximum of energy no one can question.
Sleep is far more necessary than food. One can fast for many days, or many weeks if necessary, and without any special disadvantage if he is well nourished before beginning the fast and has a satisfactory food supply after ifs conclusion, but no one can "fast" from sleep for more than a few days at a time without experiencing ill effects. One can scarcely endure an entire week of absolute sleeplessness. It has been found that dogs kept awake even though sufficiently fed, suffer more than when deprived of food and permitted to sleep. When kept awake continuously they die in four or five days. Man can endure the strain a little longer than the dogs, but five or six days usually marks the limit of human life under such conditions. In early English history condemned criminals were put to death by being deprived of sleep, and the same method has been employed in China. Enforced sleeplessness, in fact, has been used as a form of torture by the Chinese, being more feared than any other. The men subjected to this frightful ordeal always die raving maniacs.
These facts illustrate only too well the imperative necessity for sleep. Unfortunately "late hours" prevail, especially in large cities. Manifestly, if complete lack of sleep is fatal, late hours and partial lack of sleep is at least devitalizing and detrimental to health. The late hours kept by large numbers of people in civilized countries undoubtedly contribute very largely to neurasthenia and allied diseases. Improvements in artificial lights have contributed largely toward the increase of the evil of late hours, injurious not only through the loss of sleep entailed, but also because of the eye-strain incidental to strong artificial lights and the drain on the nervous system. If civilized man would follow the example of primitive man and of many of the birds and animals in retiring to bed with the coming of darkness and arising with the appearance of daylight, this one change would revolutionize the health of the whole human race.