HYGIENIC RELATIONS OF WATER.
In order to be able to appreciate the value of water as a means of preserving health, it is necessary to understand something of the structure and functions of those portions of the body to which it is directly applied; viz., the skin, externally, and the mucous membrane, in the interior of the body.
The skin is composed of two principal layers; a thin outer layer, called the epidermis, cuticle, or scarf skin, and a deeper structure, the true skin, or dermis. We will describe the latter first.
The True Skin.—This structure covers the entire surface of the body. It varies in thickness according to its location, being thickest upon the soles of the feet, the palms of the hands, the back, and the outer portions of the thighs. Its basis is a dense network of elastic fibers, among which are intricately mingled minute blood-vessels, nerve fibers, and lymphatic or absorbent vessels. These are most numerous near the upper surface, and are arranged in loops upon little elevations called papillæ. In the palms of thehands and upon the soles of the feet these papillæ are disposed in rows with so much regularity as to give to those parts a minutely furrowed appearance.
The skin also contains little sacs, or follicles, in which the hairs originate. In its deeper portions are found two kinds of glands; sebaceous glands for the secretion of sebaceous or fatty matter to lubricate the skin, and the perspiratory or sweat glands, the latter of which will receive a more definite description shortly.
The Cuticle, or Epidermis.—At the upper portion of the true skin, new cells are being constantly formed, which become old in a short time and are pressed outward by the formation beneath them of other new cells. The old cells become shriveled and flattened as they grow older, and by a continuation of the process described, numerous layers of cells are formed upon the surface of the true skin, the lowest of which is composed of newly formed cells, while the uppermost one is made up of dessicated cells having more the appearance of horny scales than of cells. These several layers constitute the epidermis, or outer skin. It is totally devoid of sensibility, and has no blood-vessels. It is, in fact, dead, and is useful only as a protection to living parts beneath.
Scattered among the cells of the epidermis are colored cells, which give to the skin its proper color. In the Caucasian race, these cells are few;in the negro, they are abundant; while in the albino, they are wholly absent.
The Sweat Glands.—A close examination of the little ridges found upon the palms of the hands, by the aid of a small magnifying glass, will reveal what appear to be fine transverse lines crossing the ridges at short intervals. A still closer inspection shows that the apparent lines are really minute openings, guarded by delicate valves. These are the mouths of the perspiratory ducts, which convey to the surface the product of the sweat glands. The gland itself is merely a coiled tube, already described as situated deep down in the true skin, and is surrounded with a network of blood-vessels. The duct is simply a continuation of the same tube upward through the cuticle to the surface. It passes out upon the surface of the skin obliquely, thus leaving a small portion of the cuticle overlapping its orifice, forming a sort of valve.
The number of these delicate glands is enormous. It has been carefully estimated to be about 2,300,000 in a single individual. The length of each is about one-fifteenth of an inch, making their aggregate length about two and one-half miles.
The Mucous Membranes.—All cavities in the body which communicate with the surface by openings are lined with a membrane which is called mucous, from the character of its secretion.The mucous membranes are continuous with the skin at the natural openings of the body, and very closely resemble it in structure, being formed of several layers, like the skin, and having a superficial portion made up of layers formed by the deeper tissues. Mucous membrane forms the lining of the air-passages and lungs, of the whole alimentary canal, and of the urinal and genital organs. Its extent in the lungs alone has been estimated by scientists at 1400 square feet, or more than seventeen times the whole extent of the skin.
Functions of the Skin.—The skin performs a number of very important offices for the body. Perhaps the most important is that of excretion. Each of its millions of sweat glands is actively and constantly engaged in separating from the blood impurities which would destroy life if retained. These foul products are poured out through a corresponding number of minute sewers, and deposited upon the surface of the body to the amount of several ounces each day, or several pounds, if the whole perspiration be included in the estimate, as is commonly done.
The skin is also an organ of respiration; it absorbs oxygen, and exhales carbonic acid gas, with other poisonous gases. The amount of respiratory labor performed by the skin is about one-sixtieth of that done by the lungs. In some of the lower animals, the whole work of respiration is performedby the skin. In the common frog, the respiratory action of the skin and of the lungs is about equal.
Another important office of the cutaneous tissue is absorption. The absorption of oxygen has been already referred to; but it absorbs liquids as well as gases, and to a much greater extent. By immersion in a warm bath for some time, the weight of the body may be very considerably increased. Dr. Watson, an English physician of note, reports the case of a boy whose weight increased nine pounds in twenty-four hours solely by cutaneous absorption of moisture from the air. This extraordinary action was occasioned by disease. Seamen, when deprived of fresh water, quench their thirst by wetting their clothing with sea-water, the aqueous portion of which is absorbed by the skin. The lymphatic vessels are believed to be the principal agents in absorption.
Another remarkable function of the skin is the regulation of temperature. By its density and non-conducting property it prevents the escape of necessary heat to a considerable degree. But when the amount of heat generated in the body becomes excessive, either from abnormal vital activities, or by exposure to external heat, the skin relieves the suffering tissues by favoring the escape of heat. This desirable end is attained through the evaporation of the moisture poured out upon the surface by the perspiratory glands.
It has been estimated that the evaporationof water from the cutaneous surface and the mucous membrane of the lungs occasions the loss each minute of sufficient heat to raise a pint of water 100° F. in temperature. This is certainly a powerful cooling process.
Lastly, we mention as a further function of the skin, and one which is not the least in importance, its utility as a sensitive surface. It is a well-established physiological fact that the mind is only a reflection of impressions received from without, or at least that its character is largely determined by the nature of the impressions made upon its organs of sensibility. The skin is the organ of touch, and the various modifications of tactile sensibility. It is the most extensive organ of sensibility in the body, and is very closely connected with all the great nerve centers, so that it is perhaps the most efficient means through which to affect the general nervous system. Its intimate sympathy with internal organs is shown in a great number of diseases in which this organ evidently suffers on account of disability of some other one.
Functions of the Mucous Membranes.—The functions of the mucous membranes are strictly analogous to those of the skin. Like the latter organ, a mucous membrane excretes and absorbs. It eliminates foul matters, and absorbs useful substances in a fluid state.
The importance of the functions of the skin isshown by the fact that a person quickly dies when its action is interrupted. A coat of varnish or caoutchouc, applied over the whole skin, will kill a man almost as quickly as a fatal dose of strychnia. In experiments upon animals, horses, dogs, and other animals have been killed by obstructing the action of the skin by some similar means. A little boy was once killed by covering him with gold leaf to make him represent an angel at a great celebration.
The offensive odor of the perspiration, and the characteristic smell of the sweat-soiled underclothing of a tobacco user, are facts which well attest the value of the cutaneous functions in removing impurities from the body.
We are now prepared to consider, understandingly,—
The Hygienic Value of Water.—If we except pure air, it may safely be said that no other element in nature sustains so important relations to the living system as does pure water. An individual will live much longer on water alone, than if deprived of drink. Water constitutes a large proportion of all our food, varying, in grains and vegetables, from fifteen to more than ninety per cent. If the water thus contained in solid food were wholly removed, an individual would doubtless be enabled to subsist longer on water only than on solid food so treated. Though water undergoes no change in the body, and hence takesno part in the development of force, it is absolutely essential to the performance of the vital functions, being necessary to enable the various organs to perform their offices in the maintenance of the vital activities.
The circulatory system is especially dependent upon this element. Water is the menstruum which floats the blood corpuscles and the varied nutritive and excrementitious elements which form the blood. By its aid, the nutrient particles destined to enter into the structure of the body are conveyed to the most minute and remote fiber of the intricate human mechanism where repair or growth is demanded. No other element in nature is so well suited to this exact purpose as water. It is so limpid and mobile that it can circulate through the most delicate capillaries without friction, and can even find its way, by osmosis, into parts inaccessible by openings.
Thirst.—Water is continually passing away from the body. The dry air entering the lungs by respiration absorbs it from the moist surface of the pulmonary membranes. A large portion is lost by evaporation from the skin, upon which it is poured out by millions of little sewers, the perspiratory ducts, for the purpose of washing away impurities from the system. The kidneys remove a considerable quantity, with poisonous excrementitious elements in solution. Through still other channels water is removed, aggregating,in all, the amount of five pints in twenty-four hours in the average individual. This loss must be made good, in order to preserve the requisite fluidity of the blood; and nature expresses the demand for water by thirst.
Some people rarely drink liquid of any kind. Others consume several pints in a day. The nature of an individual’s occupation will in a measure determine the amount of drink required. Stokers, glass-blowers, and others whose vocation necessitates profuse perspiration, require more water than others. It will be noticed, moreover, that the character of the diet has much to do with the demand for drink. Those who subsist mostly upon fruits and grains, and other vegetable productions, avoiding the use of stimulating and irritating condiments, require little or no addition to the juices contained in their food. Those who pursue an opposite course in dietetics, using largely animal food, salt, pepper, spices, and other condiments, and perhaps taking a little wine or something stronger for their stomach’s sake, are under the necessity of taking considerable quantities of fluid in addition to that provided by their food.
Water is the only substance which will quench thirst. Beverages which contain other substances are useful as drinks just in proportion to the amount of water which they contain, and are unwholesome just in proportion as the added elements are injurious.
Regulation of Temperature.—The evaporation of water from the surface of the human body is one of the most admirable adaptations of means to ends exhibited in animal life. All of the vital activities in constant operation in the body occasion the production of heat. Sometimes the amount of heat is greater than is needed, and so great as would destroy the vitality of certain tissues if it were not speedily conducted away. By evaporation of water from the skin, this is accomplished. When external heat is great, perspiration is more active than when it is less, and thus the temperature of the body is maintained at about 100° F. under all circumstances. By this wonderful provision of nature, man is enabled to exist under the great extremes of heat and cold presented in the frigid regions at the poles and the torrid climate of the equator. By the aid of clothing, human beings have survived a continued temperature of 60° to 100° below zero; and, by the protective influence of evaporation, an average of 100° above zero has been endured in tropical climes. For short periods, so great a degree of heat as 350° F., or even 600° has been borne with impunity in exceptional instances. In these cases the extreme heat which would otherwise reduce the body to a cinder in a few moments is rapidly conducted away by evaporation without occasioning any damage.
Depuration.—Every thought, every movement, the most delicate vital action, occasions the destruction of a portion of the living tissues, which is thus converted into dead matter, and becomes poisonous. Many kinds of poisonous substances are produced within the body in this way. Some of them are very deadly, and must be hurried out of the system with great rapidity, asureaandcholesterine. Here the marvelous utility of water is again displayed. It dissolves these poisons wherever it comes in contact with them, and then as it is brought by the current of the circulation to the proper organs—the kidneys, liver, skin, lungs, and other emunctories—it is expelled from the body, still holding in solution the animal poisons which are so rapidly fatal if retained.
Cleanliness.—The skin is one of the most important depurating organs of the whole body. From each of its millions of pores constantly flows a stream laden with the poisonous products of disintegration. As the water evaporates, it leaves behind these non-volatile poisons, which are deposited as a thin film over the whole surface of the skin. As each day passes, the process continues, and the film thickens. If the skin is moderately active, three or four days suffice to form a layer which may be compared to a thin coating of varnish or sizing. The accumulation continues to increase, unless removed, and soonundergoes further processes of decomposition. It putrefies, rots, in fact, and develops an odor characteristic and quite too familiar, though anything but pleasant, being at once foul, fetid, putrid, pungent, uncleanly, and unpardonable.
But the offense to the nose is not the extent of the evil. The unclean accumulation chokes the mouths of the million little sewers which should be engaged in eliminating these poisons, and thus obstructs their work. Being retained in contact with the skin, some portions are reabsorbed, together with the results of advancing decay, thus repoisoning the system, and necessitating their elimination a second time.
Here water serves a most useful end if properly applied. It is unexcelled as a detergent, and by frequent application to the skin will keep it wholly free from the foul matters described. The necessity for frequent ablutions is well shown by the fact that nearly two pounds of a poison-laden solution, the perspiration, is daily spread upon the surface of the body. It is not an uncommon occurrence to meet with people who have never taken a general bath in their lives. Imagine, if possible, the condition of a man’s skin, at the age of seventy or eighty years, which has never once felt the cleansing effects of a thorough bath!
One of the most serious effects of this accumulation of filth is the clogging of the perspiratory ducts. Their valve-like orifices become obstructedvery easily, and depuration is then impossible. It is not wonderful that so many people have torpid skins. The remedy is obvious, and always available.
How to Make the Skin Healthy.—A man who has a perfectly healthy skin is nearly certain to be healthy in other respects. In no way can the health of the skin be preserved but by frequent bathing. A daily or tri-weekly bath, accompanied by friction, will keep the skin clean, supple, and vigorous. There is no reason why the whole surface of the body should not be washed as well as the face and hands. The addition of a little soap is necessary to remove the oily secretion deposited upon the skin.
A lady of fashion, in enumerating the means for preserving beauty, says: “Cleanliness, my last recipe (and which is applicable to all ages), is of most powerful efficacy. It maintains the limbs in their pliancy, the skin in its softness, the complexion in its luster, the eyes in their brightness, the teeth in their purity, and the constitution in its fairest vigor. To promote cleanliness, I can recommend nothing preferable to bathing. The frequent use of tepid baths is not more grateful to the sense than it is salutary to the health and to beauty.... By such means, the women of the East render their skins softer than that of the tenderest babe in this climate.” “I strongly recommend to every lady tomake a bath as indispensable an article in her house as a looking-glass.”
When the foul matters which ought to be eliminated by the skin and quickly removed from the body are allowed to remain unremoved, the skin becomes clogged and inactive, soon loses its natural luster and color, becoming dead, dark, and unattractive. When bathing is so much neglected, it is no marvel that paints, powders, lotions, and cosmetics of all sorts, are in such great demand. A daily bath, at the proper temperature, is the most agreeable and efficient of all cosmetics.
Bathing Protects against Colds.—It is an erroneous notion that bathing renders a person more liable to “take cold, by opening the pores.” Colds are produced by disturbance of the circulation, and not by opening or closing the pores of the skin. Frequent bathing increases the activity of the circulation in the skin, so that a person is far less subject to chilliness and to taking cold. An individual who takes a daily bath has almost perfect immunity from colds, and is little susceptible to changes of temperature. Colds are sometimes taken after bathing, but this results from some neglect of the proper precautions necessary to prevent such an occurrence, which are carefully stated elsewhere in this work.
Aristocratic Vermin.—Doubtless, not a few of those very refined and fastidious people who spend many hours in the application of all sorts of lotions and other compounds to the face and hands, for the purpose of beautifying those portions of the skin exposed to view—while neglecting as persistently those parts of the skin protected from observation—would be very much surprised to learn the true condition of the unwashed portions of their cutaneous covering. They instinctively shrink with disgust from the sight of a vermin-covered beggar, in whose cuticle burrows theacarus scabiei(itch-mite), while troops of larger insects are racing through his tangled locks and nibbling at his scaly scalp. It is quite possible that many a fair “unwashed” would faint with fright if apprized of the fact that her own precious covering is the home of whole herds of horrid looking parasites which so nearly resemble the itch-mite as to be at least very near relatives, perhaps half-brothers or cousins. The name of this inhabitant of skins unwashed is as formidable as the aspect of the creature, though it does not require a microscope to display its proportions, as does the latter; scientists call itdemodex folliculorum.
Thedemodexmakes himself at home in the sebaceous follicles, where he dwells with his family. Here the female lays her eggs and rears her numerous progeny, undisturbed by the frictions of any flesh-brush, and only suffering a very transientdeluge at very long intervals, if such a casualty ever happens. In studying the structure of these little parasites, we have found several tenants occupying a single follicle, pursuing their domestic operations quite unmolested by any external disturbance.
Thedemodexhas been transplanted from the human subject to the dog; and it is found that the new colony thrives very remarkably, and soon produces a disease apparently identical with that known as “mange.”
We have not space to describe in detail these savage little brutes, with their eight legs, armed with sharp claws, bristling heads, sharp lancets for puncturing and burrowing into the skin, and their powerful suckers for drawing the blood of their victims. We only care to impress upon the mind of the reader the fact that neglect of bathing and friction of the skin is sure to encourage the presence of millions of these parasites, and that the only remedy is scrupulous cleanliness of the whole person. Like their relatives, the itch-mite, they do not thrive under hydropathic treatment, and are very averse to soap and water. The best way to get rid of them is to drown them out. They do not produce the irritation which characterizes the presence of the itch insect, so that this evidence of their presence is wanting. But they are sure to be present in a torpid, unhealthy, unwashed skin, no matter how delicate or fastidious its possessor.
Prevention of Disease.—Neglecting to keep the skin active and vigorous by frequent ablutions is one of the most prolific causes of nearly all varieties of skin diseases, which are too often aggravated by gross dietetic habits. The relation between the cutaneous function and that of the kidneys is so intimate that neglect of the kind mentioned, resulting as it must in obstruction of function, is a very common cause of most dangerous disorders of the renal organs. Inactivity of the skin is also very commonly associated with dyspepsia, with rheumatism, gout, hysteria, and other nervous derangements. It is also a not uncommon cause of bronchial and pulmonary affections. It is quite evident, then, that the proper and most efficient means of preventing these diseases is to maintain the functional vigor of the skin by the proper application of water.
The value of water as a prophylactic, or preventive, of disease, was recognized by the ancients, and the bath was employed by them to an extent which has never been equaled in modern times. The great Hebrew lawgiver, Moses, enjoined upon his followers the most scrupulous cleanliness, making bathing a part of their religious duties. His example was followed by the ingenious founder of Mohammedanism, who required his disciples to bathe before each of their five daily prayers. Among the Greeks, and especially the temperate Spartans, the bath was regarded as one of themost essential means of securing physical health. Daily ablutions were practiced by them, every person participating in the bath, from the newborn babe to the oldest inhabitant. The Romans cultivated bathing to a remarkable extent, making it a luxury rather than the dreaded penance which many moderns seem to regard it.
Modern Neglect of the Bath.—The most celebrated physicians, from Hippocrates down to Galen, Celsus, Boerhaave, and a host of more modern physicians, have agreed in eulogizing the bath as an invaluable means for preserving the health. Notwithstanding this fact, it seems that as civilization and enlightenment have advanced, the importance of the bath has been increasingly disregarded. The magnificent public baths of the Romans were neglected as that empire declined, until they were finally destroyed. Michelet, a historian of some note, tells us that for a thousand years during the Dark Ages the bath was unknown in Europe. This fact alone is in his opinion sufficient to account for the terrible plagues and pestilences of that period. A modern writer declares that in Spain the religious instincts of the people have become so perverted that it is considered sacrilege for a woman to bathe more than once in her life, which is upon the eve of her marriage. In more enlightened countries, it is to be hoped that the condition of the feminine cuticle is not quite so bad as this;but another writer, an Englishman, asserts that a large proportion of his countrymen “never submitted themselves to an entire personal ablution in their lives, and many an octogenarian has sunk into his grave with the accumulated dirt of eighty years upon his skin.” American customs in this respect are not much better than the English; but it is gratifying to know that a very perceptible improvement is becoming evident in both countries. Our intercourse with Oriental nations and barbarians has taught us wholesome lessons in the care of the person. There is scarcely a savage tribe to be found in the deepest jungles of tropical Africa the members of which do not pay more attention to the preservation of a clean and healthy skin than the average American or Englishman.
Bathing a Natural Instinct.—All nature attests the importance of the bath. The rain is a natural shower bath in which all vegetation participates, and gains refreshment. Its invigorating influence is seen in the brighter appearance, more erect bearing, and fresher colors, of all plants after a gentle rain. The flowers manifest their gratitude by exhaling in greater abundance their fragrant odors. Dumb animals do not neglect their morning bath. Who has not seen the robin skimming along the surface of the lake or stream, dipping its wings in the cool waters, and laving its plumage with the crystal drops whichits flapping pinions send glittering into the air? No school boy who has ever seen the elephant drink will forget how the huge beast improved the opportunity to treat himself to a shower bath, and perhaps the spectators as well, for he is very generous in his use of water.
If man’s instincts were not rendered obtuse by the perverted habits of civilization, he would value the bath as highly and employ it as freely as his more humble fellow-creatures, whose instinctive impulses have remained more true to nature, because they have not possessed that degree of intelligence which would make it possible for them to become so grossly perverted as have the members of the human race. Man goes astray from nature not because he is deficient in instinct, but because he stifles the promptings of his better nature for the purpose of gratifying his propensities.