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equally raised in the tube; but the water is found by the experiments above related, to rise of an inch more than the mercury; and therefore the water must expand so much more than the mercury by removing the weight of the atmosphere.
In order to determine how much the water was compressed by this, or a greater weight, he took a glass ball of about an inch and in diameter, which was joined to a cylindrical tube of 4 inches and in length, and in diameter about ! of an inch and by weighing the quantity of mercury that exactly filled the ball, and also the quantity that filled the whole length of the tube; he found that the mercury in of an inch of the tube, was the 100000th part of that contained in the ball; and with the edge of a file he divided the tube accordingly.
This done, he filled the ball and part of the tube with water exhausted of air; and left the tube open, that the ball, whether in rarefied or condensed air, might always be equally pressed within and without, and therefore not altered in its dimensions. Now by placing this ball and tube under the receiver of an air-pump, he could see the degree of expansion of the water, answering to any degree of rarefaction of the air; and by putting it into a glass receiver of a condensing engine, he could see the degree of compression of water, answering to any degree of condensation of the air. But great care must be taken in making these experiments, that the heat of the glass ball be not altered, either by the coming on of moisture, or its going off by evaporation ; which may easily be prevented by keeping the ball under water, or by using oil only, in working the pump and condenser.
In this manner he found by repeated trials, when the heat of the air was about 50 degrees, and the mercury at a mean height in the barometer, that the water will expand and rise in the tube, by removing the weight of the atmosphere, 4 divisions and, or one part in 21740; and will be as much compressed under the weight of an additional atmosphere. Therefore the compression of water by twice the weight of the atmosphere, is one part in 10870 of its whole bulk.* The famous Florentine experiment which so many Philosophical writers have mentioned as a proof of the incompressibility of water, will not, when carefully
If the compressibility of the water was owing to any air that it might still be supposed to contain, it is evident that more air must make it more compressible; he therefore let into the ball a bubble of air that measured near of an inch in diameter, which the water absorbed in about 4 days; but he found on trial, that the water was not more compressed by twice the weight of the atmosphere, than before. The compression of the glass in this experiment, by the equal and contrary forces acting within and without the ball, is not sensible: for the compression of water in two balls, appears to be exactly the same, when the glass of one is more than twice the thickness of the glass of the other. And the weight of an atmosphere, which he found would compress mercury in one of these balls but part of a division of the tube, compresses water in the same ball 4 divisions and Orig.
considered, appear sufficient for that purpose: for in forcing any part of the water contained in a hollow globe of gold through its pores by pressure, the figure of the gold must be altered; and consequently the internal space containing the water diminished; but it was impossible for the gentlemen of the academy del Cimento to determine, that the water which was forced into the pores and through the gold, was exactly equal to the diminution of the internal space by the pressure.
CIV. On the Solar Eclipse, October 16, 1762. By Mr. Samuel Dunn. P. 644. Mr. D. observed the solar spots instead of the sun's eclipse.
CV. Remarks on the Catarrhal Disorder, which was very frequent at London and in its Neighbourhood in May 1762; and on the Dysentery, which prevailed the following Autumn.* By W. Watson, M.D., F. R. S. p. 646.
In the beginning of May, 1762, there was at London and in its neighbourhood a disease, very epidemic, though not fatal, which had sometime before been very prevalent both in Italy and Germany. It continued during the course of the month, and some part of June. In it the breast was very much affected, and it was very frequently attended with a fever. It is nearly the same disease which was at London in April and May 1743, and then called influenza, the name applied to it in Italy. Dr. W. remarks that it is very well described by Dr. Huxham in the 2d vol. of his work, entitled, De Aere et Morbis Epidemicis, p. 101. Tho' of the same catarrhal kind, it was by no means so severe or so fatal as the disease of Feb. 1733, of which there is likewise a history in the 1st vol. of the above mentioned work, p. 80. The disorder, though very general, seemed to attack the women more severely than the men. Much bleeding did harm; and where there was no fever, which was frequently the case, the patients recovered equally well without it. Even without bleeding, or other evacuations, some, more especially women and lax-fibred men, were much debilitated during its whole continuance. The blood in most was not sizy; but the crassamentum was tender and the serum bilious. Where the heat was great, gentle emetics brought up much bile, and very much lessened the inflammatory state of the disease. The rest was to be left to blisters, if the cough was very troublesome and the stricture on the breast severe, balsamic medicines, gentle opiates, and light broths; carefully avoiding cordials of every denomination and volatiles. Towards the end of the disorder, after gentle evacuations by stool, decoctions of Cort. Peruv. were of signal service, both in recruiting the strength, and carrying off the remaining cough. In the disorder of 1743, the skin was very frequently inflamed, when the fever
* Of this catarrhal disorder (influenza) and dysentery a more complete account was afterwards published, in an elegant Latin dissertation, by Sir G. Baker.
ran high; and it afterwards peeled off in most parts of the body: but this was not observed to happen in the present disorder.
This autumn (1762) there was a disease, which had not been in Dr. W.'s remembrance epidemic at London. Very few of the physicians in London had seen this disorder as it had appeared then; but Dr. Huxham mentions it as frequent at Plymouth in the year 1743, in his treatise De Morbis Epidemicis, vol 1, p. 90, where it is observed that many of the children which fell under his care voided the vermes teretes. In the course of his practice Dr. W. found many of Dr. H.'s observations exceedingly well founded, and collected from them very useful remarks. Dr. Sydenham has left an admirable history of this disease, as it appeared at London in the year 1669, and the 3 subsequent years. To this work, as well as to what Dr. Huxham has given on this subject, Dr. W. was very much obliged.
As the dysentery is most frequently an autumnal disease, and as Dr. W. had not seen any person afflicted with it in the latter part of Dec. he flattered himself that the cold and frosty weather had put a stop to its progress. This disorder, though very general, most frequently attacked weak persons, and those recovering from other diseases, women during their lying-in, and children. The dysentery in some was attended with a fever, in a high degree inflammatory, in others it was without any fever. When it was attended with a fever, bleeding and gentle evacuations by stool with liberal dilution did great service. When there was no fever, as well as in those whose fever had been relieved by the methods before mentioned, if the irritating pain in the bowels, bloody or mucous discharges with the tenesmus continued, after the excrementitious sordes had been carried off, nothing relieved more than drinking large quantities of very small mutton broth, without salt, so as to be discharged but little altered. This not only warmed and nourished the patient, but diluted the acrimony, and served as a most comfortable fomentation to the whole intestinal canal. Clysters of this with Tinct. Theb. he directed to be given 3, or even if the symptoms were urgent, 4 times a day. When these symptoms were abated, as most persons were exceedingly debilitated and their appetite almost gone, light decoctions of Cort, Peruv. greatly hastened the recovery.
He had the misfortune to see 3 children die of 4 or 5 years old, after the severity of the disease was over. Their bowels had for a week or more been free from pain. They were without fever. Their discharges by stool both bloody and mucous were in a manner gone: yet they were so much debilitated, and their stomachs so languid, that they obstinately refused every species of nourishment by the mouth; nor would they retain nutritious clysters; so that in the end they sunk from absolute inanition. In 2 of these, which by his direction were opened, he found their gall bladders turgid with high coloured viscid bile.
In both, the stomach and bowels were perfectly empty, and their bodies emaciated to a great degree. In one, neither the stomach nor bowels were in the least degree inflamed or discoloured; except that a very few of the veins were preternaturally enlarged on the surface of the cæcum and colon. In the other, there. had been an inflammation on about 10 inches of the jejunum ; but that had been resolved; as the bowel was almost restored to its natural colour, and was not in its texture, even after death, more tender than the rest. The other viscera had not the least change of their colour, but exhibited a sound and natural appearance. Another child which he saw, was seized with a dysentery, attended with a very ardent fever, which, notwithstanding his utmost endeavours to relieve it, carried off the poor infant on the third day. Several, almost the whole, of this child's discharges by stool were nothing but blood. On opening the body after death, the whole of the intestines were in a very great degree inflamed, and of an intensely deep red colour, and the contents of the abdomen were inexpressibly fetid. Throughout the whole course of the disease, keeping the patient moderately warm, and promoting his perspiration, was of great importance; and the not sufficiently attending to this, he more than once saw followed by fatal effects. CVI. Observation of some Solar aad Lunar Eclipses at Leyden. By Mr. John Lulofs. From the Latin. p. 650.
At 7h 30m 26s A dense penumbra.
7 40 30 The true shadow at Grimaldi.
8 31 49 Digits observed were 6° 27′ 39′′.
CVII. An Account of the Gardenia. By Daniel C. Solander.* M. D. p. 654. The Gardenia is at present well known among the English gardeners by the
* Charles Daniel Solander, M. D. celebrated for his knowledge in natural history, was the son of a Swedish clergyman, and was born in the year 1736 in the province of Norland. In 1760 he travelled
name of the Cape Jasmine, though it has been but a few years in this country. It was first brought here, 1744, from the Cape of Good Hope by Capt. Hutchenson, in the Godolphin Indiaman, and by him presented to Richard Warner, Esq., of Woodford Row, Essex; in whose garden it long remained without the least sign of vegetation; but at last proved to be the most beautiful shrub that has been introduced among us for a long time. And indeed the botanic world is as much indebted to the abovenamed gentleman, for his skill and care in the preservation of the plant, as for his generosity in communicating it to the public.
When this plant first appeared, it was thought a new and unknown one to the European botanists; and though it came to blossom freely, the flowers unfortunately proved double. For notwithstanding the fructification is the only material thing in plants, whence they can be sufficiently known and described, yet double flowers are really a kind of monsters in the vegetable kingdom, as their principal parts are too much altered and distorted, for any thing to be determined from them with certainty. It therefore still remained a difficulty to ascertain what tribe this shrub belonged to; and the only way of forming any judgment, was by considering all its parts accurately, comparing them with other known plants, and thus by analogy finding out its affinity, and thence its proper place in the vegetable into England, and was recommended by Linnæus, whose pupil he had been, to Mr. Peter Collinson, and other botanists, as well as to George Edwards, the well-known ornithologist. By Mr. Collinson he is said to have been first recommended to the trustees of the British Museum, where he was some time afterwards appointed assistant librarian in the department of natural history. When Dr. Solander first arrived in England, his principal attention seems to have been turned to botany. Linnæus therefore particularly recommended him to the notice of Edwards in order that he might improve his knowledge in ornithology. The following is an extract from Linnæus's letter to Edwards on this subject.
"Has tibi, vir nobilissime, traditurus literas D. Dan. Solander meus totus est: hic in animum induxit Angliam adire, ut cognitione proficiat apud nobilissimos Anglos, apud quos hæc scientia hodie unice floret. Imprimis vero tua authoritas eum allicuit, qui summum suum habet oblectamentum in animalium historia. Est imbutus varia cognitione zoologica, sed, ut verum fatear, minus in ornithologicis versatus quam in reliquis partibus: te itaque præceptorem habere avidissimus est." In 1768 Dr. Solander accompanied Mr. (now Sir Joseph) Banks, his warm and liberal benefactor, in the voyage made round the globe by the celebrated Capt. Cooke, and during the various opportunities afforded, was indefatigable in collecting plants and other objects of natural history. In the year 1773 he succeeded, on the death of Dr. Maty, to the office of under librarian at the British Museum, in which situation he continued till his death, which took place in May, 1782, in consequence of an apoplectic stroke. As to the person of Dr. Solander, we are informed by the authors of the Biographical Dictionary, in 15 vols. 8vo, that "he was a short, fair man, rather fat; with small eyes, and good humoured expression of countenance." He was considered as a person of very extensive knowledge, to which was added a mode of communication not only remarkable for its readiness, but for its peculiar modesty. There are said to be some papers by Dr Solander scattered in the memoirs of various philosophical societies; but in the Transactions of the Royal Society of London the present paper, relative to the Gardenia, seems to have been his only production.