LECTURE VII.

Air. Clothing. Cleanliness. Evacuations. Sleep: 1. The proper time for sleep; 2. the proper quantity; 3. the means of promoting it. Manners. Influence of the Imagination and Passions upon Health.

GENTLEMEN,

Intimately connected with the subject of exercise, is that of

AIR.

Indeed when urging the importance of spending at least two hours each day in the open air, I have anticipated the most important part of this subject. A few things, however, ought to be added.

Pure air.

The clear dry air of the country, such as we breathe in this land when a mild westerly breeze prevails, is the natural state of the atmosphere, and most conducive to health. Indeed, who does not immediately feel its invigorating influence? It then consists of about 79 parts of nitrogen, and 21 of oxygen.

Bad air-evening air.

The agents that contaminate this air, are an excess of moisture, carbonic acid, and the various vegetable and animal miasms arising from putrefaction.

During clear days the sun dissipates the excess of moisture, which rises by evaporation from the land and the water. But at night it acccumulates; hence the proverbial

unhealthiness of the night air. To avoid this, should be a grand point with the invalid; or if exposed to it necessarily, it is folly not to protect himself by an additional garment. The healthy too, should always be on their guard against the damps of the evening; as no constitution can. harden itself against their morbific influence. In hot climates such exposure is the height of presumption; and in our climate, those mild and balmy evenings, which most tempt the student abroad, and induce him to saunter by the way, or to sit down under the open sky, are usually the most dangerous. A notion prevails with some, that fearless and unprotected exposure to evening air, is the way to become hardened against its influence: whereas, he is best prepared to resist it, who by temperance and vigorous exercise during the day, has imparted a healthy tone to his constitution.*

On the same principles, exercise abroad in the day time, in damp, foggy weather or in low plains, is not as good as that taken under a clear sky, and on moderately elevated ground. The damps of the morning, however, are not injurious to those in tolerable health: on the contrary, exposures then are less often followed by colds, than at any other time of the day; and indeed there is very little weather during the day, so unfavorable, as to justify the omission of the stated out-door exercise.

These same principles show us the importance of having our studies, our dwellings, and our sleeping apartments, in airy and dry situations, where they can be frequently ventilated. And if Providence should make it our duty to spend our lives in a low and marshy region, our only security lies in most vigorously adopting those rules, which serve as a security against the damps and putrid miasms that surround

us.

See Note D. D.

Crowded rooms.

By breathing, each individual renders a gallon of air unfit for respiration again, in about a minute: that is, he consumes its oxygen, or vital principle. Hence the reason why close rooms filled with people for some time, are so injurious. A hall 30 feet long, 25 broad, and 30 high, containing 22,500 cubic feet, would not permit a hundred people to remain in it more than four and a half hours; twice that number could remain in it only half the time. Hence we see the reason why theatres, ball rooms, and, indeed, any public places of meeting which continue several hours, are so injurious to the health. And the danger here is greatly increased, by being so much hidden for the person perceives little more than slight debility or headach, even when serious mischief has been done to his health. The same is true of air rendered irrespirable by the burning of charcoal in close rooms-a cause that yearly sends not a few out of the world, and debilitates many more.

It is the opinion of respectable medical writers, that the reception of other deleterious gases into the lungs, such as sulphuretted and carburetted hydrogen, exerts more influence upon the health than is generally imagined, by actually poisoning the blood.*

Unhealthiness of large towns.

These various circumstances are the cause why cities and large towns are so much more unhealthy than the open country for they are all operating more or less, in such places; though other circumstances must doubtless be taken into the account. In England the annual proportion of deaths in the large towns, is not far from one in twenty; in moderate towns, about one in twentyseven; and in small villages and the open country, about one in fortyeight. this country, the difference is not so great.

* See the Manual of the Invalid, Chap. IX. p. 141.

+ Sure Methods, &c. p. 107.

In

Also Paris on Diet,

HOW MUCH CLOTHING SHALL WE USE? 237

The chlorides.

For destroying the putrid and contagions effluvia of the rooms of the sick, and indeed, of every other place, the chloride of lime, a substance lately discovered, and mentioned in a former lecture, is by far the most effectual; and as it can be most easily and safely applied, no educated man ought to be ignorant of its uses. It can now be easily obtained at the shops of our apothecaries, with directions how to employ it.

CLOTHING.

Clothing is another point in a system of regimen, that deserves attention; especially as there are erroneous notions prevailing on the subject. Some sedentary men are engaged in the Quixotic scheme of hardening their systems by reducing themselves almost to nudity in the winter.* But even if they could succeed, it is doubtful whether it would not be at the expense of life: that is, they would probably shorten life. For it is certainly plain, both from the nature of the case and from the Bible, that men were intended to use clothing. They are the only species of animal that is not naturally provided with clothing. The only question is, how much they shall employ. And my an

swer is, enough to keep them warm. For this is the chief object of clothing. And of what service is it, except merely for decency's sake, to wear clothes at all, if this be not accomplished. To effect it, will of course require a great variety in the articles of dress, according to the age, constitution, state of weather, the health, and the season of the year. But the man whose clothing is so thin that he is shivering with the cold most of the time, may be sure that he is injuring his constitution, instead of hardening it.

"It is absurd to endeavor to inure one's self with few or thin clothes. Let but the clothing be comfortable, not too heavy; and regular exercise and regular living will be found the best means for fortifying the body against the elements.”—Journal of Health, Vol. II. p. 54.

True, he may envelope himself with as many folds of dress as an Egyptian mummy every time he goes abroad, and thus bring on an oppressive heat and debilitating perspiration; but this is not likely to prove so injurious, as the too common practice of exposure to the cold and dampness of the evening, without an additional garment. Many consumptions take their rise from this imprudence. When a person has thrown himself into profuse perspiration by exercise, he ought also to put on an additional garment, instead of endeavoring to cool himself by natural or artificial currents of air. When he goes abroad to exercise, he should be thinly dressed; but when exposed without much exercise to cold and damp air, he should put on clothes enough to secure to himself the natural warmth of the body; the feet in particular should always be kept warm and dry. This part of the frame is peculiarly sensible to the effects of cold and moisture; and a person ought never to sit down after they have been wet, until his stockings are changed. Indeed, this should be a general rule in regard to every part of the body. The absurd notion that it is better to let wet clothes dry upon one's back, has sent many to a premature grave; and the escape of any who follow such a rule, is rather to be imputed to the strength of their constitution, than to the harmlessness of the practice.

Hardening ourselves by exposure.

Great injury is often sustained by sedentary men in the spring and autumn, by attempting to harden themselves so as to live in cold, damp rooms without any fire. If indeed they were vigorously to exercise in such rooms, there would be no danger; but to sit still there until they are chilled, and this day after day, is a sure method to lay the foundation for rheumatism, consumption, and dyspepsy. True, there is some danger of making our studies too hot, so that debility will be the consequence; but small fires, rather late in the spring and rather early in autumn, are important to counteract the moisture.