Among all the millions of outside agencies that go to build up and strengthen, or if improperly used to undermine, the health of the human body, there is none so constant in our environment as air. At intervals it is necessary to eat and to sleep. At intervals it is equally essential for us to have light; but the use of air goes on from birth to death; completely deprived of it only for a few minutes we die, and it is largely because breathing is so obviously and always essential, because except in definite ill-health it is completely automatic, that few people even give a thought to the question, and most would be disposed to laugh if they were told that there are different ways of breathing, some right and some wrong. Consequently, most people with the inherent perverseness of human nature use one of the wrong ways.

Observe, for instance, the way that the first hundred people you meet down any crowded thoroughfare are breathing, and you will find probably that (leaving out of the question those who are evidently out of breath) more than three quarters have their mouths open, and are breathing through them. That is the wrong way. Many of these may have a physical difficulty in getting sufficient air through the nostrils. Some have colds, perhaps, but more have over-large adenoids. Consequently if, when you have no cold at all, you find you cannot get enough air through the nostrils without effort, go straight to a doctor. But probably you can; therefore, breathe through the nostrils. For nature, who, take her all round, is a safe guide to follow, if she clearly indicates something, has provided three passages by which air may reach the lungs. One is the mouth, two are the nostrils. But the mouth (in addition to its sense of taste most conveniently placed there) has the duty of carrying food and drink to the stomach. The chances, therefore, are that the nostrils (in addition to their sense of smell, again most conveniently placed there, a sentinel to challenge the air, as it were, as the taste is a sentinel to challenge the food) were designed to give air to the lungs. And they are not ill-contrived. Witness, to take a horrible but convincing instance, the amount of soot and smuts that are prevented from reaching the lungs if we breathe through the nose during a London fog. The nostrils are a sort of filter, tortuous, averting impurities. On the other hand, many advocates of a sensible idea (as in vegetarianism and total abstinence) are their own foes when they say that only the air warmed by the longer passage is good for the lungs and makes them less liable to catch cold. The reverse is probably the case, since people with delicate lungs are cured of their delicacy or disease in the coldest possible air, if it be dry.

Anyhow, the air gets to the lungs, otherwise we die; but the lungs, which are the largest single organ in the human body and in many ways the most adaptable, have this defect, and at the same time this enormous advantage in case of disease, that a very small part of them need be used in order to supply sufficient air to the stove of combustion. We can at will (most of us do) employ the bottom part of them only, we can (with more difficulty) employ mainly the middle part, or we can with about the same difficulty employ the upper part. But since much of the health of any organ or part of the body lies in its use, for not to use an organ either passively or intentionally implies (with the only exception of those organs which are partly intended as storers of energy) its gradual atrophy, it is clearly the path of wisdom to give the lungs their proper work. For “proper work” means not exhaustion to a healthy organ but increase of strength and health. It is on the scabbarded sword that the rust grows.

In the case of men, the use of the lower part of the lungs may at once be dismissed, for it is without exception natural and habitual, whereas in many women chest-breathing, owing no doubt largely to the use of the old and unscientific corsets, is correspondingly habitual; and for men the defect lies in hardly ever, except during violent effort, when one is out of breath, using the middle and upper breathing. Roughly speaking, lower breathing is accomplished by distention of the abdominal part of the apparatus, middle breathing by distention of the part of the body between the ribs, upper breathing by inflation of the chest. In what we call a long breath, and in a yawn, the breathing is complete throughout the whole of the lungs. It is this which is worth cultivation, not only for the sake of the lungs themselves, but for the sake of the control of breathing which is often useful.

But the main point lies in the habitual use of the whole of the lungs. Take half a dozen long slow breaths, expanding the lungs to the utmost, and again completely expelling the air, and you will find by experiment that you can hold your breath for very much longer than you could do without such preparation, the reason being that you have in the blood a store of oxygen, however minute, that will carry you on for an additional number of seconds. The advantages of this are obvious in the case of great bodily exertion when the lungs have difficulty in getting enough oxygen to supply the racing heart, for if they can easily, through thorough practice, come without effort into complete use, they will be able to supply without effort a greater fund of oxygen which automatically (and God knows how) they for ever extract from the air, returning the dead air, carbonic acid gas. In other words, the man who can without effort use the whole of his lungs will keep them in a better state of health than one who from continued non-use of the middle and upper parts of them, has not maintained them in similar vigour. Such a man, also, will be far less liable to be attacked by forms of pulmonary disease than one who has half these organs in a state which corresponds to being “below par” as applied to the whole body.

Here, as in the case of other muscles, definite exercises are good for increasing the power of the lungs.

The following will be found invariably useful:—

(1) Breathe slowly in through the nostrils till the whole of the air cavity is expanded to its fullest capacity.

(2) Hold the air there from five to ten seconds.

(3) Breathe it slowly out till the whole of the air cavity is as far as possible empty.

(4) Hold it out for from five to ten seconds.

At first this exercise will be found fatiguing to the lungs and the fatigue will be manifested, if not in giddiness, in a tendency to be out of breath. By all means be out of breath, and, when the breathing is normal again, repeat the exercise, going through it half a dozen times. After a week you will find you can repeat it a dozen times or so without intermission, or the desire for intermission. During the breathing in, it will both help the lungs and encourage a greater fulness of breath to raise the arms and shoulders. They should be held in “shrugged” position while the breath is held, be allowed to drop gradually as the breath goes out, and remain utterly relaxed during the fourth part of the exercise. This exercise will be found most beneficial in enlarging the capacity of the lungs and the power of expansion of the chest, which, by the way, is a far more important thing than the actual size of the chest. The exercise may also be used with the following (see Chapter III.):—

Stand erect with the arms outstretched and hands together in front of the face. Bring the arms quickly and suddenly back until they are level with the shoulders, still at full stretch, at the same time letting the breath come suddenly and fully into the lungs. After a pause of a second or two, with the chest inflated to its utmost, bring the arms back to the original position, expelling all the breath with the same suddenness.

These two exercises, it must be repeated, are (especially for those who need them—i.e., those who have not been in the habit of using the whole of the lungs) rather trying, particularly at first; on no account, therefore, strain or exhaust yourself over them. Let the facility in doing them come slowly. These, like all lung exercise, should be performed by an open window or in a room with good ventilation and as free as possible from dust, since the point is to charge the lungs thoroughly with air, which had therefore better be pure air. The open mouth may be used in these exercises, since a full draught of air has to be taken in suddenly.

But apart from actual exercises for the lungs, an even more important point is that these organs should as far as possible be given, night and day alike, a proper supply of air for their normal and automatic working; and their one and constant demand is oxygen. Considering how much there is in existence, it is wonderful how rare civilised life has contrived to make it, while builders and architects seem to adopt the uncompromising attitude of saying, “We will give you air and draughts, or no air and no draughts.” Sometimes even, by an excess of diabolical humour, they manage to give one draughts and no air, and render rooms both cold and stuffy; and the continual breathing of unvivified air, of air which has been exhausted of its oxygen by the breathing of other people and not renewed by a constant fresh supply coming in, is probably responsible for as much languor and indisposition as any of the errors of diet mentioned in the previous chapter. Nor is it the least necessary that because a room is hot the air should be bad; indeed, one of the reasons why a good fire in the room is healthy is that, if there is an adequate ventilator, the fire by its burning and by the passage of the heat up the chimney induces a current of air, and though it warms a room and may make it even over-hot, yet that heated air is not nearly so enervating as the air of a cooler and ill-ventilated room. The lungs do not in the least object to be fed with even roasted air, as in a Turkish bath, any more than they dislike air of the utmost extremity of cold; what they do rebel against is being given vitiated and exhausted air. It is the quality rather than the temperature of the air we breathe which has to be considered, and many people who say they cannot stand a hot room mean not really a hot room but a stuffy one.

We have heard a good deal lately about the policy of the open door, and recommend to our readers’ serious consideration the policy of the open window as much as possible by day and always at night. Unless the head of the bed is immediately by the window (and scarcely even then), it is practically impossible to catch cold when one is in bed and properly covered. To live under canvas, for instance, means to sleep almost invariably in a thorough draught. But those who have tried that delightful mode of life know that to catch cold under such circumstances is almost unknown; one is constantly wet and is usually in a draught, but one does not catch cold because these things in themselves do not produce a cold in a healthy person, and one’s health in such conditions is improved, because one has enough air and probably not too much food. The air itself is tonic, strengthening; it is largely because in civilised city-life we do not have enough that we are liable to colds. The passages to the lungs, with their lining of mucous membrane, and the lungs themselves, are clogged with impurities, and weak through a mild form of starvation. Feed them. Clean them.

We do not, however, advise the ordinary city man deliberately to sit in a draught, though if that were the only plan of getting air it might be far better than his present procedure. Instead, we recommend him to look to his ventilators, and whenever he feels that the office is stuffy let him cut another or two, one low and one high; let him—and these remarks apply to all dwellers in houses—warm his offices by fires rather than hot pipes, if possible; for fires assist ventilation while they also give heat, but pipes are valueless except for heat. Furthermore, a screen of paste-board, or if light is wanted, of glass, can often be arranged so that a window may be opened without creating a draught at all; for though draughts are not, we think, so guilty in the way of cold-giving as their reputation would seem to justify, yet they are uncomfortable. But above all have windows open during sleep, that mighty friend of recuperation, when rest ought to be brought to every organ. And the natural rest to give the lungs is to supply them with plenty of pure air, so that their work is made easy for them. Nothing is commoner than long drowsiness and heaviness on waking, even after perfectly sufficient sleep, and for this nothing is more responsible than the fact that we have been breathing all night air which has been steadily deteriorating because drained of its oxygen. Let the windows be shut by all means, if you will, while you are dressing; but while sleeping, never.

Though the lungs perform the main part of the breathing, much is done also by the skin, which has this further function of continually striving to throw off those waste products and impurities of the body which rise like scum to the surface. How vastly important these functions are is shown by the story of Pietro Riario, the boy Cardinal-Archbishop of Florence, who at a feast gilded a child all over to serve as a huge lamp bearer, with the consequence that in a few hours the unfortunate victim died. It is clearly, then, desirable to listen to the demands of the skin, which are as simple and intelligible as those of the lungs, and consist of air, warmth (though to a far less extent than is generally supposed), and cleanliness. It is by clothing and baths that we meet these demands.

Now our general method of dealing with the skin is to wrap it up and put it in the dark; in other words we cover it as much as possible, because we say it is delicate and to expose it gives us colds. It is delicate—that is quite true; but what has made it delicate is our habit of covering it up. A woman, for instance, will pass with arms, shoulders, breast, and a large part of the back bare, out of a heated ball-room into a cool sitting-room and not catch cold, because her skin is used to what—as far as the skin is concerned—is most sanitary and healthy treatment. She does not catch cold, because her skin is used to it, and one of the surest ways to guard against colds is deliberately and every day to accustom it to exposure. Reasons of decency forbid us to make this a public performance, but everyone can and should adopt some course of the following kind. Strip completely on getting up and (whether the bath, hot or cold, is taken immediately or not) go through the other incidentals of dressing, shaving, etc., without clothes on. Similarly at night undress completely at once and give the skin ten minutes’ airing before getting into bed. At the same time, it is well to avoid any feeling of chill, and if it is cold, sit before the fire a few minutes, or, better still (unless you find that they keep you awake), have a few minutes at the exercises given above, which will supply a more thorough and invigorating warmth. The effect of this simple treatment is, as we know from personal experience, quite amazing, both in its hardening virtues, whereby we are far less liable to catch cold at sudden chills or changes of temperature, in its tonic effect on the skin itself, as shewn in a vastly increased firmness and elasticity, and also in the constant and immediate feeling of freshness that it produces. We all know how vivifying is fresh air on the face only; here the whole skin is invigorated.

Not less important is the matter of clothing, which should be in the first place as natural as possible, so that it may not distort the natural shape, or cramp a natural movement. In the main, the ordinary man’s clothing, though ugly enough, is in this respect sensible, except with regard to boots, which really seem to be an invention of the devil so as to thwart in every possible way what was meant to be the natural play of the foot. Toes in a bunch, like asparagus, tightness over the insteps, and the whole infernal contraption strapped on by a cruel string cramping the muscle above, the ankle! A more insanitary contrivance, or one better calculated to cramp the muscles and distort the shape of the foot, especially if a man take much exercise on his feet, could not be devised. Moreover, there is a sort of idea that boots which conform to the natural shape of the foot must necessarily be clumsy. This is not the case; but even if it were, it would be the part of sense to go clumsily but healthily shod. What is necessary is to be carefully measured for boots with the two feet separately, and with the weight resting on the foot that is being measured, since the weight naturally spreads out and flattens the foot, and it is of the first importance to have a boot that is not cramped when the muscles of the foot are being used. It is the toes that chiefly suffer in ill-fitting boots, since the boot is, as a rule, made broad enough for the foot in repose, but does not allow for the spread of the toes which takes place (or should take place) every time a step is made. At this moment it is obvious that the toes are being used as a lever to throw the body forward to its next step, the whole weight is for the moment on them, and their natural and reasonable tendency is to flatten out. Instead of allowing for this, most bootmakers make their boots for the foot in rest, with the result that the toes get crushed together at each step. This point, doubly important in the case of children whose feet are still growing is, it is satisfactory to see, being taken into serious consideration at last, and year by year more children are allowed to wear sandals, either with or without socks—an admirable institution, for they give the foot its natural development. Many women’s feet are really altogether unfit for walking purposes owing to the persistent way in which they have been cramped from childhood upwards, following the barbaric and Chinese fashion of considering a small foot a beautiful thing. A delicately made foot of course is, but a foot naturally of moderate size and cramped of its growth is merely a shapeless lump of bent bones and packed flesh.

Secondly, clothing should be as easy as possible; there should not be pressure, except for definite medical purposes of support, on any part of a properly developed body; for pressure not only prevents the free flow of blood to the capillary vessels of the skin, but checks the play of any muscle which is being used, forbidding its expansion at the moment of its energy, and thus cramping the freedom of its movement.

Thirdly, clothing should be as light as is possible consistently with reasonable warmth. What is wanted, therefore, next the skin (in cold weather at any rate) is some material like wool, which is porous and therefore holds in its interstices innumerable little air-chambers that when once warmed by the heat of the body form between it and the outer clothing and air a layer of protection. It is exactly this plan that nature has adopted in the covering of birds, and we find the lower part of the feather-quill clad, not in the hard plumage of its tip, but in soft down which interposes a cushion of air between the body and the atmosphere. This is especially and markedly the case in aquatic birds, part of whose body is incessantly in water; the natural oil of the stiff part of the feathers is absolutely waterproof, while the down near their base prevents, by its air and warmth-holding capacities, the chill of the water reaching the body. Wool also has this advantage, that it absorbs moisture, and thus a man clad in under-garments of wool will be less liable to take cold if he gets chilled after violent exercise, since the sweat is to a large extent drawn away from complete contact with the skin.

On the other hand, cotton or silk next the skin, while it is less warming and has not the full protective advantages of wool, gives more air to the skin, since it does not cling so closely, and thus facilitates the breathing functions of the skin, and also allows more light to pass through it. Much must depend on the constitutional vigour of the skin in individual cases, and on its reacting powers. For a person naturally liable to catch cold, wool is certainly the safer clothing.

Finally, all clothing worn next the skin should be very frequently washed, for it is absorbing all day and every day the waste products of the skin; it should also be well aired before use and kept if possible, not in hermetically sealed drawers, but where air can get to it.

Perhaps no change of fashion in the last fifty years is greater than the change that has come over bedrooms. Fifty years ago the ordinary healthy man (if he could afford it) slept in a deep feather-bed into which his unfortunate body sank and was smothered; his bed was probably draped at the head with large curtains so as to prevent anything like a movement of air getting to him (not that it was very likely, for he kept his windows shut and curtained), while in case of anything so untoward happening he had an additional protection in the shape of a nightcap, while over the whole bed, as likely as not, was a heavy quilt. In fact, the bed gear of fifty years ago was all that bed gear should not be. By degrees the curtains were taken down, the feather mattress was supplanted by a thinner and harder affair which got its elasticity from springs below it, windows were opened, and the nightcap wore out and was not replaced. In fact, the proper rule—the utmost coolness consistent with comfort—came in. The head should be cool, the body not hot nor smothered airlessly beneath masses of coverlets. The feet, however, unless naturally warm, may with advantage have a rug thrown over them; for, if they are warm, proper circulation of the blood is ensured, and a most fruitful cause of insomnia removed.

To sum up in one sentence the general principles we have tried to lay down in this chapter, we should say, “When in doubt, open it or take it off”; the point being that you should whenever possible expose yourself to air. Think for a moment of the different rÉgime adopted now, not for people in health, but for consumptives, from what those unfortunates suffered thirty years ago, and think also of the vastly increased percentage of recoveries. Thirty years ago patients were sent to warm enervating places, draughts and cold were treated as if they themselves were the microbes of disease. Now air, air, air, and when the damp and dulness of English winters arrives, up they go into piercing elevations of Swiss mountains. And if air will heal definite disease, we may take it completely for granted that so natural a remedy will be highly beneficial to those in health, for it must and does act as a preventive to disease, and is in itself health-giving. So also with clothing: when in doubt take it off, for the more the skin is either directly exposed or, though clad, allowed to get the maximum possible of air and light, the healthier and the more vigorous it will become; and instead of saying, “Put on a coat, or you will catch cold,” it will be nearer the truth to say, “Continue not to put on a coat and you will not catch cold.” Of course, there are an immense number of days when, especially if one is out in the open air without taking exercise, a coat is advisable, since the feeling of being cold is a natural danger signal, and it is then our business to get warm. But the habit of being cold is often due—and this is our point—to a relaxed and unvigorous condition of the skin, and the coat is, as it were, only a dose to meet a special need, whereas the rational treatment is to get the skin into such a condition that the body is less liable to feel cold. And this diminished liability to feel cold is promoted, not by covering the skin up, but by accustoming it to be uncovered.