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binson, in our Philosophical Transactions, volume 59, page 30, for the year 1757. He asserts, that fat persons with small bones float most easily upon water.

The diving bell is accurately described in our Transactions.

When I was a boy, I made two oval pallets, each, about ten inches long, and six broad, with a hole for. the thumb, in order to retain it fast in the palm of my hand. They much resemble a painter's pallets. In 'swimming 1 pushed the edges of these forward, and I struck the water with iheirflat surfaces as I drew them back. I remember I swam faster by means of these

pallets, but they fatigued my wrists I also fitted to

the sales of my feet a kinds of sandals; bue I was not satisfied with them, because I observed that the stroke is partly given with the mside of the leet and the ancles, and not entirely with the soles of the feet.

We have here waistcoats for swimming, which are made of double sail cloth, with small pieces of cork quilted in between them.

I know nothing of the scafihandrc of M. dela Chapelle. I know by experience that it is a great comfort to a swimmer, who has a considerable distance to go, to turn himself sometimes on his back, and to vary in other respects the means of procuring a progressive motion.

When he is seized with the cramp m the leg, the method of drivmg it away is to give the parts affected a sudden, vigorous, and violent shock; which he may do in the air as he swims on his back.

During the gteat heat of summer there is no danger in bathing, however warm we may be, in rivers which have been thoroughly warmed by the sun. But to thiow o.iesf:lf mto cold wa'er, wh..n the body has been heated by e*erei-.e inttie sun, is an imprudence which in.iy prove fatal. I once knew an inatanceioffouryoung men, .vnv, havmg worked at harvest in the heat of the day, with a view of refreshing themselves plunged intoa sprint* of old waie': two died upon the spot, a third lite next mornmg, and tuc fourth recovered vt4h gteat difficulty. A .copious draught of cold water, in similar circumstances, is frequently attended with the same effect in North America.

The exercise of swimming is one of the most healthy and agreeable in the world. After having swam; an hour or two in the evening, one sleeps coolly ,th« whole night, even during the most arnent heat of sum-. mer. Perhaps the pores being cleansed, the insensible perspiration increases and occasions this coolness. It is certaiu that much swimming, is the means of stopping a diarrhoea, and even of producing a constipation. With respect to those who do not know how to swim or who are affected with a diarrhoea at the season v.hji Vi does not permit them to use that exercise, a warm bath,. by cleansing and purifying the skin, is found very salutary, and often effects a radical cure. 1 speik from my own experience, frequently repeated, and that oF ethers to whom I have recommended this.

You will not be displeased if I conclude these hasty remarks by informing you, that as the ordinary method ©f swimming is reduced to the act cf rowing with the arms and legs, and is consequently a laborious and fatiguing operation when; the space of water to be crossi.d is considerable; there is a method in which a swimmer may pass a great distance with much facility, by means of a sail. This discovery I fortunately made by accident, and in the following manner.

When I was a boy I amused myselfone day with flying a paper kite; and approaching the bank of a pond, which was near a mile broad, I tied the string to a stake, and the kite ascended to a very considerable height above the pond, while I was swimming. In a little time, b^ing desirous of amusing myself with my kite, and enjoying at the same time the pleasure of swimming, I returned ; and loosing from the stake the string with the little stick which was fastened to it, went again ino the water, where I found, that, lying on my back and holding the slick in my hands, I was drawn alocg.the surface ci". the water in a very agreeable manner. Havmg then engaged another boy to earrjp Biy clothes round the pond, to a place which I pointed cut to him on the other side, I began to cross the pond 'witlj my kite,,which carried me quite over without the least fatigue, and with the greatest pleasure imaginable. I was only obliged occasionally to halt a little in my course, and resist its progress, when it appeared that, by following too quick,! lowered the kite too much; by doing which occasionally I made it rise again. I have never since that time practised this singular mode, of swimming, though I think it not knpossiuie to crosft in this manner from Dover to Calais. The packet. Jfo*t however, is still preferable.



London, July 28, 1768.. I Greatlt approve the epithet you give, in you* letter of the 8th of June, to the new method of treating the small-pox, which you call the tonic or bracing me-, thod; I will take occasion, 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; tut the shock of the cold water has always appeared tome, generally speaking, as too violent, ai.d 1 have found it much more agreeable to my constitution to bathe in another element, I mean cold air. With this view t 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. This practice is not in the least painful, but, o» 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 «f .least it does not injure my health, if it does not in fact contribute much to its perservation.—I shall there.-' fere 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 net ones, because I doubt the f.ict. I imagine that neither the one nor the other contribute to this effect, and that the causes of colds are totally mdependent of wet and even cold. I propose writing a.short paper on this subject, the first leisure moment I have at rny disposal—In the mean time I can only say, that having suspicions that the common notion, which attributes to cold the property of stopping the pores and obstructing perspiration, was ill founded, I engaged a young physician, who is making some experiments with Santoriusts 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 dot' trines of Life and Death.


Your observations on the causes of death, and the experiments which you propose for recalling to Iif» 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 but littl». understood.

A toad, buried in sand, will live, it is said, until irre sand becomes petrified; and then, being inclosed ir\ the. stone, it may still live for we know not hew marvy S %

ages. Tlie facts which ave Cited in support of tfiis' opinion are too numerous and too circumstantial not to' deserve a certain degree of credit. As we are accus-. tomed to see all the animals with wiiich 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 slate, 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, serpents, 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.. loots 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 color. 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.

1 have seen an instance of common flies preserved ire si 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 wasj three drowned flies fell'into the first glass. Which was filled* Having heard it remarked that' browned flies were capable*>f being revived by the rays •f the sun, I proposed making the exptriment upon 4hese* They were therefore exposed to the sun, upon

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