« 上一頁繼續 »
treating the small-pox, which you call the tonic or bracing method : I will take occasions from it, to mention a practice to which I have accustomed myself. You know the cold bath has long been in vogue here as a tonic ; but the shock of the cold water i as always appeared to me, generally speaking, as too violent, and I have found it much more agreeable to my constitution to bathe in another element, I mean cold air. With this view I rise early almost every morning, and sit in my chamber, without any clothes whatever, half an hour or an hour, according to the season, either reading or writing. I his practice is not in the least painful, but on the contrary, agreeable; and if I return to bed afterwards, before I dress myself, as sometimes happens, I make a supplement to my night's rest 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 ocGasion 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 ! l'opose 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 some suspicions that the common notion, which attributes 10 cold the property of stopping the pores and obstructing perspiration, was ill-founded, I engaged a young physician, who is making some experiments with Sanctorivus's. balance, 'to estimate the different proportions of his Berspiration 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 PREVAIL ING DOCTRINES of LIFE and DEATH.
TO THE SAME.
VOUR observations on the causes of death, and
I 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 aces: 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 acs quainted 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 torpici state, perspiring less because they use no exercise, should have less need of alement ; and that others, which are covered with scales or shells, which stop perspiration, such as land and sea turtles, serpents, and some species of fish, should be able to subsist a considerable time without any nourish
ment 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 from 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 commodia ous method of transporting from distant countries those delicate plants whieh are unable to sustain the inelemency 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 Alies 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 tl:eir legs, wiped their eyes with their forefeet, beat and brushed their wings with their hind feet, and soon after began to fly, find. ing themselves in Old England, without knowing how they came thither. The third continued lifeless until sun-set, when, losing all hopes of him, he was thrown away.
I wish it were possible, from this instance, to invent 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 turkey-cock.
PRECAUTIONS to be used by those who are about te
undertake A SEA VOYAGE.. U THEN you intend to take a long voyage, no
VV thing is better than to keep it a secret till the momentof 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 thou. sand things which you wish to remember, so that when you are embarked, and fairly at sea, you recol. lest, with much uneasiness, affairs which you have not terminated, accounts that 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 to suffer a trava eller, 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 people of this description, but they are not common ; however, if yours 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 cantiot 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 undoubt. edly 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 gave 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