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receive greater heat can escape; so living bodies do not putrify, if the particles as fast as they become putrid, can be thrown off. Nature expels them by the pores of the skin and lungs, and in a free open air, they are carried off; but in a close room, we receive them again and again, though they become more and more corrupt. A number of persons crowded into a small room, thus spoil the air in a few minutes, and even render it mortal, as in the Black Hole at Calcutta. A single person is said to spoil only a gallon of air per minute, and therefore requires a longer time to spoil a chamber full ; but it is done, however, in proportion, and many putrid disorders hence have their origin. It is recorded of Methusalem, who being the longest liver, may be supposed to have best preserved his health, that he slept always in the open air ; for, when he had lived five hundred years, an angel said to him : “ Arise, Methusalem ; and build “thee an house, for thou shalt, live yet five hundred "years longer." But Methusalem answered and said: “ If I am to live but five hundred years longer, it is “not worth while to build me an house-I will sleep “in the air as I have been used to do.” Physicians, after having for ages contendeed that the sick should not be indulged with fresh air, have at length discovered that it may do them good. It is therefore to be hoped that they may in time discover likewise that it is not hurtful to those who are in health ; and that we may be then cured of the aerophobia that at present distresses weak minds, and make them choose to be stifled and poisoned, rather than leave open the windows of a bed-chamber, or put down the glass of a coach.
Confined air, when saturated with perspirable matter,* will not receive more ; and that matter must re
* What pysicians call the perspirable matter, is that vapour which passes off from our bodies, from the lungs, and through the pores of the skin. The quantity of this is said to be five eighths of what we eat.
main in our bodies, and occasion diseases: but it gives some previous notice of its being about to be hurtful, by producing certain uneasiness, slight indeed at first, such as, with regard to the lungs, is a trifling sensation, and to the pores of the skin a king of restlessness which is difficult to describe, and few that feel it know the cause of it. But we may recollect, that sometimes, on waking in the night, we have, if warmly covered, found it difficult to get asleep again. + We turn often without finding repose in any position. This figgettiness, to use a vulgar expression for want of a better, is occasioned wholly by an uneasiness in the skin, owing to the retention of the perspirable matter—the bed clothes having received their quantity, and, being saturated, refusing to take any more. To become sensible of this by an experiment, let a person keep his position in the bed, but throw off the bed-clothes and suffer fresh air to approach the part uncovered of his body; he will then feel that part suddenly refreshed; for the air will immediately relieve, the skin, by receiving, licking up, and carrying off, the load of perspirable matter that incommoded it. For every portion of cool air that approaches the warm skin, in receiving its part of that vapour, receives therewith a degree of heat, that rarefies and renders it lighter, when it will be pushed away, with its burthen, by cooler, and therefore heavier fresh air; which, for a moment supplies its place, and then, being likewise changed, and warmed, gives way to a succeeding quantity. This is the order of nature, to prevent animals being infected by their own perspiration. He will now be sensible of the difference between the part exposed to the air, and that which remaining sunk in the bed, denies the air access: for this part now manifests, its uneasiness more distinctly by the comparison, and the seat of the uneasiness is more plainly perceived, than when the whole surface of the body was affected by it.
Here, then, is one great and general cause of unpleasing dreams. For when the body is uneasy, the mind will be disturbed by it, and disagreeable ideas of various kinds, will, in sleep, be the natural consequences. The remedies, prevestative and curative, follow :
1. By eating moderately, as before advised for health's sake less perspirable matter is produced in a given time; hence the bed-clothes receive it longer before they are saturated ; and we may, therefore, sleep longer, before we are made uneasy by their refusing to receive any more.
2. By using thinner and more porous bed-clothes, which will suffer the perspirable matter more easily to pass through them, we are less incommoded, such being longer tolerable.
3. When you are awakened by this uneasiness, and find you cannot easily sleep again, get out of bed, beat up and turn your pillow, shake the bed-clothes well, with at least twenty shakes, then throw the bed open, and leave it to cool;; in the mean while, continuing undrest, walk about your chamber, till your skin has had time to discharge its load, which it will do sooner as the air may be drier and colder. When you begin to feel the cold air unpleasant, then return to your bed; and you will soon fall asleep, and your sleep will be sweet and pleasant. All the scenes presented to your fancy, will be of the pleasant kind. I am often as agreeably entertained with them, as by the scenery of an opera. If you happen to be too indolent to get out of bed, you may, instead of it, lift up your bedclothes with one arm and leg, so as to draw in a good deal of fresh air, and, by letting them fall, force it out again. This, repeated twenty times, will so clear them of the perspirable matter they have imbibed, as to permit your sleeping well for some time afterwards. But this latter method is not equal to the former
Those who do not love trouble, and can afford to have two beds, will find great luxury in rising, when they wake in a hot bed, and going into the cool one. Such shiftings of beds would also be of great service to persons ill in a fever, as it refreshes and frequently procures sleep. A very large bed, that will admit a removal so distant from the first situation as to be cool and sweet, may in a degree answer the same end.
One or two observations more will conclude this little piece. Care must be taken, when you lie down, to dispose your pillow so as to suit your manner of placing your head, and to be perfectly easy; then place your limbs so as not to bear inconveniently hard upon one another, as for instance, the joints of your ancles : for though a bad position may at first give but little pain, and be hardly noticed, yet a continuance will render it less tolerable, and the uneasiness may come on while you are asleep and disturb your imagination.
These are the rules of the art. But though they will generally prove effectual in producing the end intended, there is a case in which the most punctual observance of them will be totally fruitless. I need not mention the case to you, my dear friend: but my account of the art would be imperfect without it. The case is, when the person who desires to have pleasant dreams has not taken care to preserve, what is necessary above all things,
ADVICE TO A YOUNG TRADESMAN.
WRITTEN ANNO 1748.
To my Friend A. B.
As you have desired it of me, I write the following hinta,
which have been of service to me, and may, if observed, be 80 to you.
REMEMBER that time is money. He that can earn ten shillings a day by his labour, and goes abroad, or sits idle one half of that day, though he spends but sixpence during his diversion or idleness, ought not to reckon that the only expense; he has really spent, or rather thrown away, five shillings besides.
Remember that credit is money. If a man lets his money lie in my hands after it is due, he gives me the interest, or so much as I can make of it during that time. This amounts to a considerable sum where a man has good and large credit, and makes good use of it.
Remember that money is of a prolific generating nature. Money can beget money, and its offspring can beget more, and so on. Five shillings turned is six; turned again, it is seven and three pence; and so on till it becomes an hundred pounds. The more there is of it, the more it produces every turning, so that the profits rise quicker and quicker. He that kills a breeding sow, destroys all her offspring to the thousandth generation. He that murders a crown, de stroys all that it might have produced, even scores of pounds