CHAPTER XL.

CLOTHING.

=Physiological Considerations.=—The average temperature of the surface of the body in man is 98·4 to 98·6°. The maintenance of a tolerably uniform temperature is an essential condition of life. The factors governing the temperature of the body are _the amount of heat produced_ and _the amount lost_. If more heat escapes, more has to be generated; and the source of all the heat produced in the body is the food taken. This becomes changed by the metabolic processes occurring in the body which produce heat.

=Heat is lost=, (1) by the _skin_; (2) in _respiration_, the expired air having been heated during its stay in the lungs; (3) with the _food and drink_ taken, if not at the temperature of the body; (4) with the _excreta_; and (5) by transformation of heat into _mechanical energy_. Of the whole loss by these different channels, probably eighty to ninety per cent. is through the skin.

=The Loss of Heat by the Skin= is in three different ways. First, by _conduction_, when the skin comes in contact with anything cooler than itself; secondly, by _radiation_ into space; and thirdly, by _evaporation_ of the perspiration. The last cause produces a considerable reduction of temperature, even when the perspiration is not so abundant as to be visible, but is in the form of insensible perspiration. The losses by these different sources vary in amount; when one is increased, another is diminished, by way of compensation. Thus, in very cold weather, the amount of radiation and conduction of heat are increased; but evaporation greatly decreases, and the diminished loss of heat in this respect counter-balances in some degree the increased loss by radiation and conduction.

When the external warmth is considerable, increased evaporation occurs; while when the weather is cold, the cutaneous arteries contract, and less blood goes to the skin, and so the loss of heat is diminished. In most climates, however, this action of the skin requires to be supplemented by some kind of clothing.

=Requisites of Dress.=—1. The first and most important requirement is that _clothing should maintain a uniform and equable temperature_ in all parts of the body.

In hot climates clothes are required in order to protect the body from external heat. In this country, they are required to prevent the too rapid escape of heat from the body. For both these purposes, dress must be of a non-conducting material, in order not to encourage transfer of heat into or from the surrounding atmosphere.

The loss of heat by the skin may be prevented by interfering with radiation or conduction of heat, or with evaporation from its surface. Radiation of heat from the skin is prevented by clothing, the dress taking the place of the skin as a radiating surface. The amount of radiation from the dress will depend on the rapidity of conduction of heat from the skin. The amount of conduction and of radiation of heat will vary considerably with the _material_ and _colour_ of the dress.

As regards =conductivity=, the two extremes are represented by linen and fur. It is found that if the conducting power for heat of linen = 100, then that of wool = 50 to 70. This partly explains why woollen goods are so much warmer than linen. We shall find that there is another explanation in the relative hygroscopic properties of the two materials.

As regards =radiation= of heat, in one experiment it was found that while a piece of linen took 10½ minutes to cool, a corresponding piece of flannel took 11½ minutes.

Apart from the material, the =colour of dress= has some influence in regulating the loss of heat. Dark-coloured materials absorb more light and heat than lighter coloured materials; they may be good or bad conductors of heat, according to the nature of the material. White reflects the rays of light and heat; hence it is a poor absorber. In summer it prevents the passage of heat inwards, and, in winter, may prevent its passage from the body. It is thus well adapted for both winter and summer clothing, and has the additional advantage of being the cleanest colour.

Franklin placed a number of squares of different coloured cloths of the same material on snow, and found after a time that the snow covered by the black piece was most, and by the white piece least melted. In another set of experiments, shirting materials dyed various colours were taken, and it was found that if the rays of heat received by white were represented as 100, pale straw received 102, dark yellow 140, light green 155, Turkey red 165, dark green 168, light blue 198, black 208.

The influence of colour is antagonised to a large extent by the nature of the material; the increased heat absorbed by a dark material may be counterbalanced by the material being a good conductor. Also the influence of colour is only exerted superficially; hence, although it produces considerable effect in thin textures, as gauze, it has little influence on thick materials.

2. _The dress should not interfere with perspiration._ In order that it may not do this, it should be competent to absorb moisture easily, without its surface becoming wetted. Materials like linen which lose their porosity and rapidly become wetted by perspiration, cause rapid loss of heat from the body, inasmuch as water is a better conductor of heat than air. Pettenkofer found that while the maximum hygroscopic power of wool (flannel) is 174 and the minimum 111; the maximum of linen is 75 and the minimum 41. Hence, with a flannel vest next the skin, the liability to chill is much less than with a linen one. There is one slightly counterbalancing drawback; hygroscopic materials absorb moisture from the air, as well as from the skin. A woollen coat during a damp day, without rain, increases considerably in weight.

Waterproof clothing is injurious when worn beyond a short period, on account of its being non-porous and consequently keeping the body enveloped in a vapour bath composed of its own perspiration. For a similar reason India-rubber boots are objectionable, except for short periods; they make the feet damp, and even sodden. Sealskin jackets are objectionable for walking, not only because of their weight, but because they are not porous.

3. _The warmth of clothing should be uniformly distributed_ throughout the body. This principle is very frequently departed from; and consequently one part may be chilled while another is over-heated. This is seen especially in female apparel. The same evil is seen in the short sleeves, and short and low-necked dresses of young children. “Combination” garments for women, and sleeves and leggings for young children are happily becoming more generally adopted, and will diminish the diseases due to exposure to cold.

4. _The clothing should not be tight_; and this for three reasons. First, because _loose clothing is warmer_ than tight; this everyone has experienced in the case of gloves. The retention of air in the meshes of clothing is one of the main causes of its warmth, air being a bad conductor of heat. The imprisonment of air in the meshes of the material largely explains the warmth of eider-down quilts, furs, and flannels as contrasted with linen.

Secondly, clothing should not be tight, in order _to avoid interference with the action of the muscles_. Tight sleeves prevent the muscles of the arms and chest from being exercised. Tightly laced corsets imprison the trunk muscles, prevent their contractions, and so lead to muscular weakness and occasionally spinal curvature. Tight skirts similarly prevent free play of the lower limbs, leading to a halting gait, a diminished amount of exercise, with all the evils following deficient exercise. Tight clothing is not confined to one sex, and in all cases leads to hampered movements and deficient muscularity.

Thirdly, tight clothing tends to _impede the functions of circulation, respiration, and digestion_. The fashion which more than any other interferes with important functions is _tight-lacing_. This produces (1) compression and displacement of the viscera; the liver and the stomach especially suffer. (2) Respiration and circulation are impeded, the action of the diaphragm being impeded. (3) The muscles of the trunk being tightly encased, are incapable of movement, and consequently tend to waste and atrophy. The general outline of the body is altered. Instead of the waist being elliptical, as it naturally is, it becomes nearly circular; and instead of its circumference averaging twenty-six to twenty-seven inches, it may be eighteen to twenty-one inches. Tight _garters_ tend to produce varicose veins.

_Tight boots_ are injurious, as they tend to destroy the natural elasticity of the movements, and confine them within narrow limits. They act to some extent the part of splints. By interfering with the circulation of blood through the feet, they cause cold feet, and not uncommonly chilblains. _High-heeled boots_ do not allow the natural elasticity of the foot to come into action. They distort the movements of the body and cause corns and bunions. Similar effects are produced by boots which are too narrow and have pointed toes, thus not allowing free movement of the toes.

5. _The weight of the clothing should be the smallest amount consistent with warmth, and it should be evenly distributed._ The chief weight should not be suspended from the waist, as here the parts are not well supported by bones. The shoulders and hips should share in the suspension of clothing, thus diminishing the danger of compression and displacement of internal organs. In order that garments may be as light as possible, they should be made to fit to each limb separately, thus diminishing the amount of material required.

6. _The materials of dress should be as far as possible non-inflammable._ This may sometimes be disregarded, but is often important, as in the nursery. In this respect, as in many others, wool possesses great advantages. Woollen fabrics smoulder rather than burst into flames, and thus the injury resulting from any accident is limited. Cotton is more inflammable than linen, linen than silk, and silk than wool. A closely woven cloth is less inflammable than one with open meshes.

Dress materials, and more particularly muslin, have been rendered non-inflammable by treating with a solution of ammonic phosphate, or ammonic phosphate and ammonic chloride mixed. The best material, however, is sodic tungstate, which, unlike the others, is not affected by ironing. Sodic molybdate is used in arsenals to render the workmen’s clothing non-inflammable. All the above plans are objectionable, as the weight of the material is increased 18 to 29 per cent., and they all wash out. To remedy this, a “fire-proof starch,” containing sodic tungstate has been devised.

Perfect non-inflammability is only required in certain dangerous occupations. The plans hitherto mentioned simply prevent the fabric breaking out into flame. The only cloth absolutely unaffected by fire is asbestos cloth.

7. _Elegance of dress_, although not so important as utility, is not to be neglected, and the two are perfectly compatible. In fact, elegance is indirectly associated with utility, for nothing which is awkward, or leads to obstructed movements or distortions of the body, is really elegant. A sudden constriction, as in a very tight waist, is not only bad from a hygienic point of view, but is also ugly.

=Materials for Clothing.=—The materials used are derived partly from the vegetable world, as hemp, flax, cotton; and partly from the animal world, as silk, wool, hair, feathers. The most important materials are wool, silk, cotton, and flax.

1. _Wool_ varies somewhat in character, according to the animal from which it is derived. In all its varieties, however, it preserves the character of a bad conducting and porous substance, the two most important requisites in a dress material.

(1) Wool from the sheep is really a soft and elastic hair, composed of fibres three to eight inches long, and about 1∕1000 inch thick. The finer and shorter wools are used for fine cloth, the longer and coarser for “poplins,” “worsted pieces,” etc. Flannel is a woollen stuff of rather open and slight fabric. Wool is irritating to delicate skins, and may be so much so, that it cannot be worn next the skin, whether as flannel, worsted, or merino. In these cases, it may be worn outside a linen or gauze vest, and so all its advantages secured. It is one of the worst conductors of heat, and ought always to be worn in winter; while even in summer, it ensures a greater immunity from chill after perspiration than any other material.

(2) _Cashmere_ is made from the down found about the roots of the hair of the Thibet goat. Imitation cashmere is made of various materials mixed together.

(3) _Alpaca_ is obtained from the fleece of the llama, alpaca, and vicuna. It is longer than the fleece of the sheep, the fibres, which are soft and strong, averaging six inches in length. It is commonly made up with cotton or silk.

(4) _Mohair_ is the hair of a goat inhabiting the mountains near Angora. It is woven into an almost waterproof cloth, and used in making plush, braid, etc.

2. _Hair_ derived from the horse or cow differs from the hair usually called wool, in the greater solidity of its structure, which makes it ill adapted for clothing. Its chief use is in the manufacture of felts, of which hats are made.

3. _Leather_ is a kind of natural felt, very close and firm in its texture. It is used in this country chiefly for boots, but in some colder climates also for coats, etc. It is impervious to moisture, like sealskin, and is consequently not very healthy. The same objection applies to _chamois-leather underclothing_, which is non-porous, and consequently keeps the skin hot and clammy; also, it cannot be washed without becoming stiff on drying. This necessitates wearing the material after it has become impregnated with perspiration.

4. _Silk._ The thread spun by the silk-worm is composed of filaments 1∕2000 inch wide, and is the strongest and most tenacious of textile fabrics. Its thread is three times as strong as a thread of flax of the same thickness, and twice as strong as a thread of hemp.

Its fibres are round like those of linen, but softer and smaller; it gives an agreeable sensation of freshness to the skin even more than linen. It is a worse conductor of heat than cotton or linen. Its great disadvantage for wearing next the skin, apart from its expense, is that it irritates delicate skins. _Satin_ is silk so prepared as to form a smooth, polished surface.

_Velvet_ is a silk fabric of which the pile is due to the insertion of short pieces of silk thread under the weft or cross-thread. Cheaper kinds are made, containing a certain proportion of cotton.

_Crape_ is made of raw silk gummed and twisted to form a gauze-like fabric. Taffety, moire, brocade, and plush are made of silk alone or combined with cotton.

5. _Cotton_ consists of the downy hairs investing the seeds of the gossypium plant. The threads of which it is composed are flat, ribbon-like, and twisted, about 1∕800 to 1∕2000 inch wide. Owing to its flat fibres with sharp edges, it is apt to irritate delicate skins; linen is preferable for dressing wounds for a similar reason. Cotton is warmer than linen, being a worse conductor of heat. It also absorbs moisture better, not becoming wet so soon; but it lacks the “freshness” which makes linen materials pleasant to wear. Calico, fustian, jean, velveteen, and muslin are the chief cotton fabrics.

6. _Flax_ is formed from the fibres of the flax plant. Linen is made from it. Cambric and lawn are very fine and thin linen materials. The fibres of linen are round and pliable; thus it is smooth and soft, and peculiarly agreeable to the skin. It is, however, a good conductor of heat, and consequently “it feels cold” to the skin. Furthermore its pores quickly become filled with perspiration, which escapes rapidly, thus chilling the body.

7. _Mackintoshes_ are valuable as a temporary protection against external wet. Worn for more than a short period, they produce great heat and a sense of closeness, owing to retention of the perspiration. The best form of mackintosh is one having a cape, with a space for evaporation between it and the rest of the garment.

=The Amount of Clothing required= varies with circumstances. 1. _Health_; those of robust constitution require less than the feeble. The more active are digestion and assimilation, the less is the amount of clothing required. If heat is preserved by clothing, less food is required. Thus a distinct saving of food is effected by warm clothes. Warm clothes are the equivalent of so much food that would have been required to keep up the temperature of the body, if the clothes had not been worn. Thinly clad persons under conditions of starvation die more quickly than those who are better protected.

2. Clothing requires to be adapted to _climate and season_. In winter and in cold climates the amount of clothing must be increased, and warmer materials chosen. In the changeable climate of Great Britain, it is difficult to adapt the character of one’s dress to the requirements of the weather. _Clothing ought, however, not to be changed according to the calendar_, but according to the weather. The tendency is to assume summer clothing too early in the spring, and to continue it too far into the autumn. According to Boërhave, winter clothing should be put off on Midsummer day, and resumed the day after. This, although rather exaggerated, may serve to impress the caution required. The same authority says that only fools and beggars suffer from cold, the latter not being able to procure sufficient clothes, the former not having the sense to wear them.

3. _Age._ Those at the two extremes of life are specially susceptible to cold. The mortality of infants during the first three months of life is nearly doubled in winter. Bronchitis and pneumonia prove fatal chiefly at the two extremes of age.

The younger a child the larger is its surface as compared with its bulk, inasmuch as the area of a body varies as the square of its dimensions, while its mass varies as their cube. Thus a cube 1 inch each side has 6 square inches of surface to 1 cubic inch of bulk, while a cube 10 inches each side has 600 square inches of surface to 1000 cubic inches in bulk. Similarly a child 1∕10 the size of its mother, besides its feebler powers of producing heat, has ten times as much surface in proportion to its size by which heat is lost.

After the age of thirty-five, it is better to exceed than to be deficient in clothing. A degree of cold that would act as a useful tonic to the robust and middle-aged, produces serious and even fatal depression of the vital powers in children or aged people. For the same reason it is advisable to discontinue cold baths as age advances.

A very pernicious delusion is prevalent, that children ought to be “hardened” to the influences of cold, and that too much clothing “makes them tender.” Excessive clothing may possibly increase the tendency to “catch cold,” owing to its exciting perspiration, or owing to the fact that the extra clothing is commonly thrown off at irregular intervals—witness the effects of wearing a scarf round the neck occasionally. But to suppose that children can be hardened by exposure of arms and legs, and other parts of their bodies, is irrational. A large amount of heat is lost from these bare surfaces, and apart altogether from the danger of chill, more food must be taken to compensate for this loss of heat, and keep up an equable temperature. Also if the food taken is expended in preserving the warmth of the unprotected body, less material is left for the purpose of growth. From these causes it frequently happens that children remain stunted in growth, even if latent disease is not actually developed by the extra strain on their resources.

The children of the very poor are often pointed to as demonstrating the power of hardening. It is forgotten how many of these poor children have perished under the hardening system, and that the good health of those remaining is in spite of the hardening.

=Poisonous Dyes in Clothing.=—These, like poisonous wall-papers, were formerly much more common than at present, and, as in wall-papers, the poisonous agent has most frequently been arsenic, large quantities of which were formerly used in the preparation of certain dyes. Occasionally such poisonous pigments are still employed.

The means of detecting arsenic in any fabric or wall-paper are given on page 216.