The skin or covering of the human body consists of an outer layer called the cuticle, and of an inner one, the corium. These constitute the true skin, but under them lies a third layer of cellular tissue, which is considered also as part of the skin, when that term is used in its most comprehensive sense. In man the skin is covered more or less with scattered hairs, profuse in some parts and scanty in others. The office of the skin is one of protection to the organs beneath, and it is also a vast excretory or eliminative system, sending out moisture with waste matter in solution through the sudoriferous or sweat glands located in its structure. Each of these glands consists of a long line tube, situated in the cutaneous cellular tissue and coiled into a knot near its closed end. This constitutes the gland proper. Then there is connected with it a straight or spiral duct that traverses the outer layers and ends in a surface opening called a pore. Nearly three thousand of the latter are found upon a square inch of the palm of the hand, and at least five-hundred on an equal space upon other parts of the body.

Perspiration is the watery matter "breathed out" from the system through the pores described. It is more copious than the exudation from the lungs by respiration, but the amount discharged varies greatly, as it is affected the heat or the dryness of the atmosphere, by liquids consumed, by exercise, and by the relative activity of the kidneys. Sensible perspiration is that which is perceptible in the form of small drops, but by far the larger portion exuded is of the insensible or non-visible kind. Solid matter is carried to the surface of the skin in the sweat, and authorities all agree that a considerable proportion of the total waste of the body is evacuated in this manner.

Close sympathy exists between the functions of the skin and those of the lungs, the kidneys, the liver, and the bowels, and this is evidenced in that, when one or other of the latter organs is disabled in function, perspiration is sympathetically deranged and vice versa. This does not necessarily mean that the effect produced is that of physical transference of the suppressed exhalation to the internal organ or the reverse, although this may be so; but the chief impression seems to be made upon the nervous system. The importance of the relation existing between the skin and the other excretory organs is such that it cannot be disregarded when disease is to be remedied.

In order to insure full functional activity of the surface of the body, frequent bathing is necessary. For this purpose one daily cleansing bath is essential in health. By it, dead, scaly particles of skin, dirt, and the products of perspiration are removed, the pores are cleared of surface obstruction, and the other eliminative organs are relieved of the performance of extra labor. When, as in the fast, the process of elimination is active in the extreme, cleansing baths may never be neglected.

A cleansing bath is a hot bath. One at temperature of about 105 degrees Fahrenheit is cleansing in the highest degree if pure vegetable oil soap be freely-used and the brush or cloth be vigorously plied. During a fast the temperature of the water in the daily bath or baths should upon entrance be approximately 100 degrees, and it should be gradually increased to as high as 107 or 110 degrees, with about twenty minutes submergence as the time limit. Baths such as this are not only cleansing, but are relaxing and tonic in effect. In cases of lowered temperature, habitual or temporary, the latter as in fasters' chilliness, correction to normal register, with systemic equalization of circulation, is rapidly effected by resorting to this therapeutic agency. Its very apparent benefits are due not only to the artificial raising of body heat, but to the process of osmosis, or interchange of fluids, that takes place in the capillary tubes constituting the pores of the skin. Cold baths should never be employed during a fast. They have but slight cleansing properties, but in health they exert a powerful stimulating action on the circulation and the nervous system.

Because of the oily nature of the waste brought by perspiration through the pores to the surface of the body, the skin can never be rendered perfectly clean with water alone. Hence the recommendation concerning the use of pure vegetable oil soap.

While the ancients made use of and elaborated the bath for purposes not only of cleanliness but also of social and intellectual objects, after the advent of Christianity and its domination of the civilized world, the bath fell into disrepute. Departure from the cleanly habit of body characteristic of early civilization was due directly to the rise and growth of the religion of Christ. The church frowned upon the care of the body, deeming it as negligible in comparison with the soul. And the early fathers in instances went so far as to impose penance upon those who gazed at the nakedness of their own bodies. Cultivated modesty, prudishness, thus had its part in the reversion that took place from the bathing habits of the Greeks and the Romans. Centuries later John Wesley uttered the aphorism, "Cleanliness is next to Godliness," but whether his reference was to the mind rather than to the body, it is impossible now to know.

Not so long ago the bathtub was generally condemned by medical authority in the United States, and about the time this was happening the cultured city of Boston by ordinance made bathing unlawful, save on the advice of a physician. However, be it said in extenuation of the hygienic condition of the Bostonese, the ordinance was characterized by slack enforcement and was finally repealed, but not until 1862. The good doctors of that generation averred that bathing, especially in winter, led to phthisis, rheumatic fevers, inflammation of the lungs, and to the whole category of zymotic disease. In the public prints bathing was inveighed against as subversive of democratic simplicity and of pioneer hardihood. And even today the medical profession is chary of advice regarding the hot cleansing bath, as, they say, it is weakening in its effects.

It is said that the first bathtub to be built and used in the Republic was that of one Adam Thompson, a citizen of Cincinnati, who installed his lead-lined, mahogany-covered receptacle in the year 1842. Water was supplied from the kitchen stove by way of the tea-kettle. His temerity appeared as a gross misdemeanor in the eyes of the press, the public, the medical profession, and the legislatures of those days. Later, in 1851, President Fillmore braved public opinion and placed the first bathtub in the White House.

There is no doubt that today in the mechanical conveniences connected with the bath, America surpasses the bathing arrangements of other ages and other races, but socially and sanitarily we have yet some distance to go before reaching the bathing standards and facilities of ancient Persia, of Rome, and of present-day Japan. The ages-old warm bath habit of the Japanese causes them to look with the scorn of the elect upon those who are so uncivilized as to omit a daily hot cleansing bath. Yet it is this habit that is one of the great factors in that over-crowded land that makes for the remarkable health and vigor of the Japanese as a race.

The skin is the natural clothing of the body. Its protection to the parts beneath is aided by sub-cutaneous deposits of fat, a non-conductor of heat, distributed more or less uniformly over the body. When heated, evaporation of perspiration cools; when chilled, closed pores retain the.body warmth. Like the lungs the skin permits of blood oxygenation through the walls of the capillaries, those small veins that ramify its substance, and, as has been stated, it is an organ of elimination as well. In the conservation of body heat, the skin is thermostat of the organism. It regulates temperature, and acts as a governor of internal function. If its work be interfered with by the interposition of substances between it and outer air, evaporation from its surface cannot take place freely, and elimination of the products of the pores is impeded if not arrested. In the latter case temperature is heightened artificially and abnormally, for prevention of skin activity causes retention of heat developed internally, and health suffers.

A striking exemplification of the close sympathy noted as existing between the functions of the skin and those of the other eliminative organs is given in cases of cutaneous burns where large areas are affected. Respiration is increased to exhaustion, and kidney discharges are heavily laden with waste that in the ordinary instance is eliminated through the pores. If an extreme proportion of skin area is seared, virtual suffocation ensues. Fatal results accompanied with symptoms similar to those in asphyxiation also follow when the body is covered with a substance, such as gold-leaf, that is impervious to air.

In this connection it is not generally known that burns or scalds upon the skin may be sucessfully treated by submergence of the part affected in water. The exquisite pain of such injury is at once relieved by this procedure, and continuing the latter for hours or even days permits natural healing processes to act with despatch and surety. If the skin area seared is extensive, placing the sufferer in a full bath and keeping him there for the time necessary will often serve to save life. The water in the tub should be at constant temperature and must be frequently changed, while water in quantity should be given the patient to drink.

The customs entailed by civilization are responsible for a number of physiological evils. While modesty is, in its origin, independent of clothing, for nakedness of body by no means involves the absence of this quality, nevertheless in civilized communities the world over modesty compels body concealment, and, because of conventional covering, the skin has for ages been permitted but partial function. Since clothing is deemed essential to decency, in order to reduce its effects upon the skin to a minimum, it should be fashioned of material as light and as pervious to air as is possible, while the skin itself should be cleansed and cared for with constancy and diligence.

Because of clothing the two great mediums through which energy is delivered to the human organism, pure air and sunshine, are in large part denied contact with its outer covering Clothing prevents full elimination of perspiration and its products, the latter remaining to clog the pores. This condition may be relieved to a degree by daily exposing the naked body to the air and to the light of the sun, and air-baths and sunbaths will be found valuable agents in compelling the skin to functional activity. During a fast, weather permitting, these baths should be taken with the subject upon the ground in open air.

In health a cold bath should never be undertaken immediately after a meal, but, with regard to a hot bath this caution is unnecessary. When the menstrual flow in woman is in progress, medical dicta to the contrary, a hot body bath and vaginal douche are daily essential for cleanliness and for relief and ease in function. The relaxing effect of a hot tub bath, together with resulting equalization of circulation, alleviates congestion and pain, if present, and in conjunction with other natural agencies cited herein, leads ultimately to permanent relief.

During a fast or while on restricted diet, the patient frequently experiences a sensation of chilliness with or without change in pulse and temperature. The source of this phenomenon, "fasters' chilliness," lies in nervous reaction following the absence of food stimulation, and, at times, in the absorption of liquid waste from the intestines. The enema will correct the latter condition, and a therapeutic bath taken as soon as the sensation of chill occurs will serve at once to equalize the circulation and to restore temperature and pulse to normal, if the latter are in any degree deranged. Baths for this purpose may and should be repeated as often as needful, if proper precaution is observed. In cases of greatly lowered vitality, when temperature is habitually below register, hot therapeutic baths should frequently be given, three or four daily usually proving not too many. Cold therapeutic baths for assistance in reducing fever should be more cautiously used. In any contingency, the therapeutic bath, hot or cold, should be administered only under competent direction.