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to obtain the one kind, and avoid the other; for whether real or imaginary, pain is pain and pleasure is pleasure. If we can sleep without dreaming, it is well that painful dreams are avoided. If, while we sleep we can have pleasing dreams, it is, as the French say, tante gagne, so much added to the pleasure of life.
To this end it in the first place, necessary to be careful in preserving health, by due exercise, and great temperance; for, in sickness, the imagination in disturbed ; and disagreeable, sometimes terrible ideas are apt to present themselves. Exercise should precede meals, not immediately follow them; the first promotes, the latter, unless moderate, obstructs digestion. If, after exercise, we feed sparingly, the digestion will be easy and good, the body lightsome, the temper cheerful, and all the animal functions performeci agreeably. Sleep, when it follows, will be natural and undisturbed. While indolence, with full feeding, occasion nightmares and horrors inexpressible ; we fall from precipices, are assaulted by wild beasts, murderers, and demons, and experience every variety of distress. Observe, however, that the quantities of food and exercise are relative things ; those who move much may, and indeed ought to eat more ; those who use little exercise, should eat little. In general, mankind, since the the improvement of cookery, eat about twice as much nature quires. Suppers are not bad, if we have not dined ; but restless nights naturally follow hearty suppers, after full dinners. Indeed, as there is a difference in constitutions, some rest well after these meals; it costs them only a frightful dream, and an apoplexy, after which they sleep till doomsday. Nothing is more common in the newspapers, than instances of people, who, after eating a hearty supper, are found dead a-bed in the morning.
Another means of preserving health, to be attended ta, is the having a constant supply of fresh air in your
bed-chamber. It has been a great mistake, the sleep. ing in rooms exacıly closed, and in beds surrounded by curtains. No outward air, that may come into you, is so unwholesome as the unchanged air, often breathed, of a close chamber. As boiling water does not grow hotter by longer boiling, if the particles that receive greater heat can escape ; so living bodies do not putrisy, 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-ful; 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 year's 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 bave been used to do.” Physicians, after having for ages contended that the sick should not be indulged with fresh air, have at length discovered that it may do tliein 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 acrotihobia 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 mata ter,* will not receive more ; and that matter must remain in our bodies, ad occasion diseases : but it gives some previous notice of its being about to be hurtful, by producing certain uneasinesses, slight indeed at first, such as, with regard to the lungs, is a trifling sensation, and to the pores of the skin a kind of reste lessness which is difficult to describe, and few that feel it know the cause of it. But we may recoilect, 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 rarifies and renders it lighter, when it will be pushed away, with its burthen by cooler, and therefore heavier fresh air ; which, for a moment, sup. plies its place, and then, being likewise changed, and warmed, gives way to a succreding 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
* What physicians call the perspirable matter, is that vapour which passess off from our bodies, from the lungs, and through the pores of the skin. The quantity of this is said to be five.eights of what we eat
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, preventative, 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 meanwhile, 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 pleasing 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 yur bed-clothes 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, ree peated twenty times, will so clear them of the persp;..
rable matter they have imbibed, as to permit your sleeping well for some tinte 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 shifting of beds would also be of great service to persons ill of 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 neces-sary above all things,
A GOOD CONSCIENCE