The object of clothing is twofold: to protect the body against the weather, particularly against changes in the weather, and secondly, to protect the body against injury. Included in the former are the defenses against the elements of cold, wet, and heat; while the protection against injury is chiefly a matter of shoes. As has been pointed out, a large part of the food consumed by the body is utilized in the production of heat, whereby the body temperature is maintained at about 98 degrees Fahrenheit. A large part of this heat is continually being lost from and through the skin by radiation and evaporation, and evidently some regulating influence must be provided so that the amount of heat given off may be adjusted to variations of the external temperature. To be sure, the skin itself acts as a regulator, since a rise in temperature causes the blood vessels on the surface to distend so that a larger quantity of blood is distributed over the surface and thereby more freely evaporated. Fall of temperature, on the contrary, causes a contraction of the blood vessels and therefore a reduction in the evaporation. But this is not sufficient where external temperature undergoes wide variations, as in the northern and central parts of the United States, and a modification of the clothing is a necessary supplement. The main object of clothing, then, is not to keep out cold or heat, but to preserve and make uniform the evaporation from the body. It is an agent of the same sort as food in so far as the body temperature is concerned, and without doubt light clothing requires a greater amount of food; while, on the other hand, warm clothing will make possible a lighter diet.
The best non-conductor of heat is still air, and if one could always remain in quiet air, no clothing of any sort would be necessary, even in the most severe weather, because the air itself would serve as a garment and would prevent radiation from the body. Therefore, loose, porous garments containing air in their folds and pores are much warmer than a single, tightly woven garment, and the same material made up in three or four thicknesses will give the body far more warmth than an equal weight of texture made up in a single thickness. Similarly, a tight garment is much less warm than a loose one. A practical demonstration of this fact is found in the comparative lack of warmth in an old, much-washed, quilted, bed blanket which is very heavy but quite lacking in warmth compared with a light fluffy woolen blanket, newly purchased.
Much has been written on the advantages of woolen underwear, on the ground that since clothing is intended to retain the body heat and since wool acts as a more effective non-conductor of heat than either cotton or linen, therefore the woolen undergarment is of the greatest value. Another argument urged in favor of woolen undergarments is that they check the chill resulting from excessive perspiration, since the non-conducting power of wool prevents any rapid evaporation of perspiration responsible for the lower temperatures. For this reason, woolen undergarments are always recommended for those climbing mountains or in occupations where violent exercise is likely to be followed by rest or quiet in cold air. The objection to woolen undergarments at all times is that with sensitive skins irritation may take place, and the odd saying of Josh Billings becomes pertinent, namely, that "the only thing that a wool shirt is good for is to make a man scratch and forget his other troubles." Underwear woolen only in part may take the place of all-wool garments and have the further advantage of being less expensive. The amount of clothing worn in winter depends, or should depend, on the character of the occupation of the wearer.
Formerly, heavy woolen underclothes were almost universally worn throughout the winter without regard to the employment of the individual. When an out-of-door occupation was pursued a large part of the time or when the temperature indoors was hardly above freezing, then heavy clothing was essential; but now that much time is spent in a well-heated house or office, heavy clothing is as objectionable as overheated rooms, and the comfort and health of the body will be much better preserved by not increasing the weight of clothing except when exposed to the outer air. It must be remembered, however, that old persons, whose circulation is impaired and who are forced to lead sedentary lives, will always have difficulty in maintaining the body heat unless the outer temperature is high, and for such, woolen undergarments are very useful. The outer garments in winter, to be efficient, must have two qualities, namely, an impervious surface so that winds may not penetrate and a loose open weave in which air may be held so that warmth may be secured.
Rubber boots, although very common in the country, are not desirable as a foot covering, because they do not allow the perspiration to evaporate, but rather hold the foot in a moist condition very detrimental to it. Rubber-cloth overshoes or arctics are much better than rubber boots, and felt overshoes are equally satisfactory. Chilblains are fostered by the use of rubber boots, and cloth shoes are a great relief when the feet are thus affected.
Ventilation of bedroom.
Since the agitation for fresh air has become so extensive and the knowledge of the dangers of tuberculosis so widespread, much more attention has been given to the ventilation of bedrooms, and whereas formerly the night air was religiously excluded from a sleeping room, it is not at all uncommon now for a window to be kept wide open, even through the coldest nights of winter. From what has already been said on the subject of ventilation, it is plain that to breathe over and over one's expired air is not healthy, and while it is possible that a bedroom may be so large that the concentration of the organic matter in the air may not affect an individual sleeping in the room, yet in most cases it must be admitted that the bedroom is so small or the number of people in the bedroom so large that this possibility does not exist. It is, again, possible that the structure of the house may be so poor that it is not necessary to open a window to get plenty of fresh air; the writer remembers sleeping in rooms where, with the windows shut, paths of snow across the floor in the morning showed the intimate connection between the inside and the outside of the room.
But the tendency nowadays is to build better houses, to cover the walls with paper, to put on double windows, and even to paste up the cracks to make the room as air-tight as possible. To sleep in such a room without a window open may not be committing suicide, but it is a deliberate method of reducing the vitality, of insuring a headache or a numbed and stupid mental condition, and of loading up the system with poisons which ought to be eliminated by the oxygen which fresh air supplies. It would add many years to the lives of the people of this country if, from childhood up, the habit was formed of sleeping with the window open. Nor need one fear that a cold would result from such exposure. A cheesecloth screen in the window prevents any draft and yet allows perfect ventilation. The face is trained to all kinds of exposure without any danger of catching cold, and there is no reason why, if the bed clothing be sufficient, the night air should not be thoroughly enjoyed without danger. Of course, the bed clothing must be sufficient; two lightly woven blankets are always better than one heavy one. Wool is better than cotton; if a cotton quilt is used, it should be loose and not tied tightly.
Bathing.
An important function of the skin is to expel objectionable elements coming from the breaking down of the cells and from digestive processes; the skin is quite as important a factor in getting rid of this waste matter as those other processes more commonly considered in this connection. This action goes on most energetically when the secretion of perspiration is abundant and when the temperature of the surrounding air is so high that perspiration does not evaporate as rapidly as discharged. All these secretions contain more or less solid material which, unless removed, accumulates on the surface of the skin to clog up the glands and, in some cases, to putrefy and decay. It is this decay of organic matter on the surface of the skin which causes the odors plainly noticeable in a crowd, particularly in the winter time. This accumulation can be prevented only by frequent bathing and by wearing clean clothes, and there is no surer indication of a proper self-respect than the habit of cleanliness, both as to one's person and one's clothes. There is also the very practical feature that cleanliness is an effective method of discouraging infection and disease, partly by the removal of scurf and partly by the greater healthfulness of the skin thereby induced.