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of one or two hours of the most pleasing sleep that can be imagined. I find no ill consequences whatever resulting from it, and that at least it does not injure my health, if it does not in fact contribute much to its preservation. I shall therefore call it for the future a bracing or tonic bath.
March 10, 1773.
I shall not attempt to explain why damp clothes occasion colds, rather than wet ones, because I doubt the fact ; I imagine that neither the one nor the other contribute to this effect, and that the causes of colds are totally independent of wet and even of cold. I propose writing a short paper on this subject, the first leisure moment I have at my disposal. In the mean time I can only say, that having sonie - uspicions that the common notion, which attributes to cold the property of stopping the pores and obstructing perspiration, was ill-founıled, I engage a young physician, who is making some experiments with Sanctorius's balance, to estimate the different proportions of his perspiration, when remaining one hour quite naked, and another warmly clothed. He pursued the experiment in this alternate manner for eight hours successively, and found his perspiration almost double during those hours in which he was naked.
OBSERVATIONS ON THE GENERALLY PREVAILING DOCTRINES OF LIFE
TO THE SAME.
YOUR observations on the causes of death, and the experiments which you propose for recalling to life those who appear to be killed by lightning, demonstrate equally your sagacity and humanity. It appears that the doctrines of life and death, in general, are yet but little understood.
A toad, buried in sand, will live, it is said, until the sand becomes petrified; and then, being inclosed in the stone, it may still live for we know not how many ages. The facts which are cited in support of this opinion, are too numerous and too circumstantial not to deserve a certain degree of credit. As we are accustomed to see all the animals with which we are acquainted eat and drink, it appears to us difficult to conceive how a toad can be supported in such a dungeon. But if we reflect, that the necessity of nourishment, which animals experience in their ordinary state, proceeds from the continual waste of their substance by perspiration : it will appear less incredible that some animals in a torpid state, perspiring less because they use no exercise, should have less need of aliment; and that others, which are covered with scales or shells, which stop perspiration, such as land and sea turtles, serperts, and some species of fish, should be able to subsist a considerable time without any nourishment whatever. A plant, with its flowers, fades and dies immediately, if exposed to the air without having its roots immersed in
a humid soil, from which it may draw a sufficient quantity of moisture, to supply that which exhales fr m its substance, and is carried off «continually by the air. Perhaps, however, if it were buried in quicksilver, it might preserve, for a considerable space of time, its vegetable life, its smell and colour, If this be the case, it might prove a commodious method of transporting from distant countries those delicate plants which are unable to sustain the inclemency of the weather at sea, and which require particular care and attention.
I have seen an instance of common flies preserved in a manner somewhat similar. They had been drowned in Madeira, wine, apparently about the time when it was bottled in Virginia, to be sent to London. At the opening of one of the bottles, at the house of a friend where I was, three drowned flies fell into the first glass which was filled. Having heard it remarked that drowned flies were capable of being revived by the rays of the sun, I proposed making the experiment upon these. They were therefore exposed to the sun, upon a sieve, which had been employed to strain them out of the wine. In less than three hours two of them began by degrees to recover life. They commenced by some convulsive motions in the thighs, and at length they raised themselves upon their legs, wiped tħeir eyes with their fore feet, beat and brushed their wings with their hind feet, and soon after began to fly, finding themselves in Old England, without knowing how they came thither. The third continued lifeless until sunset, when, losing all hopes of him, he was thrown away.
I wish it were possible, from this instance, to in vent a method of embalming drowned persons, in such a manner that they might be recalled to life at any period, however distant; for having a very ardent desire to see and observe the state of America an hundred years hence, I should prefer to an ordinary death, the being immersed in a cask of Madeira wine, with a few friends, until that time, then to be recalled to life by the solar warmth of my dear country. But, since, in all probability, we live in an age too early, and too near the infancy of science, to see such an art brought in our time to its perfection, I must, for the present, content myself with the treat, which you are so kind as to promise me, of the resurrection of a fowl or a turkeycock.
Precautions to be used by those who are about to under
take a Sea Voyage.
WHEN you intend to take a long voyage, nothing is better than to keep it a secret till the moment of your departure. Without this, you will be continually interrupted and tormented by visits from friends and acquaintances, who not only make you lose your valuable time, but make you forget a thousand things which you wish to remember; so that when you are embarked, and fairly at sea, you recollect, with much uneasiness, affairs which you have not terminated, accounts which you have not settled, and a number of things which you proposed to carry with you, and which you find the want of every moment.
Would it not be attended with the best consequences, to reform such a custom; and suffer a traveller, without deranging him, to make his preparations in quietness, to set apart a few days, when these are finished, to take leave of his friends, and to receive their good wishes for his happy return ?
It is not always in one's power to choose a captain ; though great part of the pleasure and happiness of the passage depends upon this choice, and though one must for a time be confined to his company, and be in some measure under his command. If he is a social sensible man, obliging, and of a good disposition, you will be so much the happier. One sometimes meets with peo.
ple of this description, but they are not common; how: ever, if yo'ırs be not of this number, if he be a good seaman, attentive, careful, and active in the management of his vessel, you may dispense with the rest, for these are the most essential qualities.
Whatever right you may have, by your agreement with him, to the provisions he has taken on board for the use of the passengers, it is always proper to have some private store, which you may make use of occasionally. You ought, therefore, to provide good water, that of the ship being often bad; but you must put it into bottles, without which, you cannot expect to preserve it sweet You ought also to carry with you good tea, ground coffee, chocolate, wine of the sort you like best, cyder, dried raisins, almonds, sugar, capillaire, citrons, rum, eggs dipped in oil, portable soup, bread twice baked. With regard to poultry, it is almost useless to carry any with you, unless you resolve to undertake the office of feeding and fattening them yourself. With the little care which is taken of them on board ship, they are almost all sickly, and their flesh, is as tough as leather.
All sailors entertain an opinion, which has un doubtedly originated formerly from a want of water, and when it has been found necessary to be sparing of it, that poultry never know when they have drank enough; and that when water is given them at discretion, they generally kill themselves by drinking beyond measure. In consequence of this opinion, they give them water only once in two days, and even then in small quantities : but as they pour this water into troughs inclining on one side, which occasions it to run to the lower part, it thence happens that they are obliged to mount one upon the back of another in order to reach it; and there are some which cannot even dip their bcaks in it Thus continually tantalized and tormented by thirst, they are unable to digest their food, which is very dry, and they soon fall sick and die. Some of them are found thus every morning, and are thrown into the sea; whilst those which are killed for the table