was, that it was attended with an uncommon tremour of the air, and every where in those counties very sensibly shook the glass-windows and doors in the houses, and according to some, even the houses themselves, beyond the usual effect of cannon, though near; and Mr. Cruwys at Tiverton, on this occasion, lost a looking-glass, which being loose in its frame, fell out on the shock, and was broken. We do not yet know the extent of this prodigious sound, which was heard, against the then easterly wind, in the neighbourhood of London; and by the learned Dr. Tabor, who distinctly heard it beyond Lewes in Sussex.

An Account of some Experiments to find how much the Resistance of the Air retards falling Bodies. By J. T. DESAGULIERS, LL.D.— [1719.]

I TOOK twelve balls, six of which were solid leaden globes of about two inches diameter; three hollow glass balls of about five inches diameter; and three light pasteboard hollow globes of about the same diameter; and having carried them to the upper gallery in the lantern, on the dome of St. Paul's church, I let them fall down by two at a time in the following

manner:

First, a leaden ball and a glass ball; 2dly, a leaden ball and a glass ball; 3dly, a leaden ball and a glass ball. Then I let fall, in the same manner, the three other leaden balls, each with a pasteboard ball.

After that, having the leaden and pasteboard balls brought up again, I repeated the experiment twice more with a leaden and pasteboard ball; then I made the experiment twice more with a pasteboard ball alone, to see how long it would be in falling.

On the whole it appeared, that the leaden balls were a very little more than 4 seconds in falling; the two largest of the glass balls six seconds; and the pasteboard balls 63 seconds.

The height of the gallery, from whence the bodies fell, was 272 feet above the pavement of the church, then covered with boards, on which they fell.

A pail of water thrown down met with such a resistance in falling 272 feet through the air, that it was all turned into drops like rain.

On the Plague at Constantinople. By EMANUEL TIMONE, M.D.

It is proved by historical documents, as well as by daily observation, that the plague is brought from Egypt to Constantinople. Here it is fostered and retained; and although this city is scarcely ever free from the seminia of a former pestilence, yet a new fomes of contagion is every now and then imported. It is for the most part suppressed by a severe degree of winter cold.

The following are the symptoms; namely, fever, buboes, carbuncles, exanthemata, head-ache, phrenitis, drowsiness in some, wakefulness in others, anxiety, debility, or great prostration of strength, dull or muddy appearance of the eyes, palpitation of the heart, dryness of the tongue, vomiting, hiccup, worms, diarrhoea, bleeding at the nose, bloody urine, spitting of blood; pains of the side, liver, kidneys, and other parts. To these I add a weariness and soreness of the limbs, shivering sometimes followed by heat, but more frequently not; nausea without vomiting, vertigo, trembling of the hands from the very beginning of the disorder. Of these symptoms there is not one which is inseparable from the disorder, not even buboes, carbuncles, and exanthemata. In many instances there is no fever. Hence it may be established as a general rule, that whenever a disorder is accompanied with buboes, carbuncles, &c. we may with certainty pronounce it to be the plague; but that although such symptoms be wanting we cannot with certainty pronounce the contrary. Thus many who are seized with the plague experience merely a slight shivering, not so much as in a common cold; and for several days none of the characteristic symptoms show themselves, but at length they burst forth all at once. Some after taking the infection only feel a degree of languor: they are capable of walking about, and going through their usual occupations without inconvenience; but on the third or fourth day they suddenly drop down, and die on the spot.

In some constitutions the plague remains dormant for several days, and then comes into action. If a person who is recovering from the plague commits any great error in diet before the fortieth day, and a fresh bubo appears, he dies. It is very unusual for a person who has been perfectly recovered from an attack of the plague, to have it a second time during the same year. A person who had lived in an infected house for some months without taking the plague, was at length seized with it. Old men, for the most part, escape infection; young persons, on the contrary, are very liable to take it.

Foreigners are more susceptible of it than the native inha. bitants. Of all nations the Armenians are the least liable to infection. They eat very little animal food, but are much addicted to the use of onions, leeks, garlick, and wine. It is not safe to eat pork during the plague. Nothing predisposes more to the taking of infection than passions of the mind, and particularly grief and fear. Houses which are kept clean and neat are not so readily infected as those that are dirty. Cachectic subjects, and persons labouring under the jaundice and various other chronic disorders, either entirely escape infection, or if they take the plague, they have it favourably. On the contrary, it is particularly fatal to persons of a florid complexion and robust constitution.

In 1712 the plague at Constantinople spread with increasing prevalency at the end of May, and arrived at its height towards the end of July. A person whom I employed to make observations counted above ninety dead bodies in one day. The Etesian winds blew strongly; afterwards the wind changed to the south. The first week after this change in the wind, viz. to the south, he counted only about forty dead bodies per diem; the second week, about thirty; the third week, not so many as twenty; which last is not more than the ordinary number of daily deaths at that time of the year in healthy

seasons.

Of the Infinity of the Sphere of fixed Stars. By EDMUND HALLEY, LL.D.- [1720.]

THE system of the world, as it is now understood, is taken to occupy the whole abyss of space, and to be as such actually infinite; and the appearance of the sphere of fixed stars, still discovering smaller and smaller ones, as we apply better telescopes, seems to confirm this doctrine. And, indeed, were the whole system finite, though never so extended, it would still occupy no part of the infinitum of space, which necessarily and evidently exists.

I have attentively examined what might be the conséquence of an hypothesis, that the sun being one of the fixed stars, all the rest were as far distant from one another as they are from us; and by a due calculation I find, that there cannot, on that supposition, be more than 13 points in the surface of a sphere, as far distant from its centre as they are from one another and I believe it would be hard to find how to place 13 globes of equal magnitude, so as to touch one in the centre; for the 12 angles of the icosaedron are from one

another very little more distant than from its centre; that is, the side of the triangular base of that solid is very little more than the semi-diameter of the circumscribed sphere, it being to it nearly as 21 to 20; so that it is plain that somewhat more than 12 equal spheres may be posited about a middle one; but the spherical angles or inclinations of the planes of these figures being incommensurable with the 360 degrees of the circle, there will be several interstices left, between some of the 12, but not such as to receive in any part the 13th sphere.

Hence it is no very improbable conjecture, that the number of the fixed stars of the first magnitude is so small, because this superior appearance of light arises from their nearness; those that are less showing themselves so small by reason of their greater distance. Now there are in all only 16 fixed stars, in the whole number of them, that can indisputably be accounted of the first magnitude; of which four are Extra Zodiacum; viz. Capella, Arcturus, Lucida Lyræ, and Lucida Aquila, to the north; four in the way of the moon and planets, viz. Palilicium, Cor Leonis, Spica, and Cor Scorpii; and five to the southward, that are seen in England, viz. the foot and right shoulder of Orion, Sirius, Procyon, and Fomalhaut; and there are three more that never rise in our horizon, viz. Canopus, Acharnâr, and the foot of the Centaur. But that they exceed the number 13 may easily be accounted for from the different magnitudes that may be in the stars themselves; and perhaps some of them may be much nearer to one another than they are to us; this excess of number being found singly in the signs of Gemini and Cancer.

Account of a Boy who lived a considerable Time_without Food. By PATRICK BLAIR, M.D.- [1720.]

THIS account is of a boy, of 15 years of age, said to have lived three years without eating or drinking; during which time he had several severe fevers, with sometimes the loss of the use of his limbs, and one while of his speech. After the three years he gradually recovered tolerable health, excepting the use of one of his limbs, and taking extremely little food.

Concerning a new Island lately raised out of the Sea, near Tercera, one of the Azores. By THO. FORSTER, Esq. JOHN ROBINSON, master of a small vessel, arrived at Tercera, Dec. 10. 1720; near which island he saw a fire break

M

:

out of the sea. Dec. 18. we got under sail at 12 o'clock at night, and stood from Angras, S.E. The next day at two in the afternoon, we made an island, all fire and smoke; and continued our course till the ashes fell on our deck, like hail or snow, all night. We bore from it, the fire and smoke roaring like thunder, or great guns. At day-break we stood towards it again at 12 o'clock we had a good observation, two leagues south from it. We sailed round it, and so near, that the fire and matter it threw out, had like to have done us damage: but a small gale at S. E. sprung up, and carried us clear, to our great joy. The breeze was accompanied with a small shower of rain, which caused a great dust to fall on our deck. With this breeze we stood away for Tercera. The governor informed us that the fire broke out Nov. 20. 1720, in the night, and that it was accompanied by an earthquake, which shattered many houses in the town of Angra, and places adjacent. Prodigious quantities of pumice-stones and half-broiled fish were found floating on the sea, for many leagues round the island, and abundance of sea-birds hovering about it.

Observations on the Figures of Snow. By the Rev. BENJ. LANGWITH, D.D.- [1723.]

ON Jan. 30. 1723, a little after nine in the morning, weather cold, wind south-westerly, but not very high, barometer above 30 inches, I saw that pretty phenomenon of the starlike snow, and though on comparing my observations afterwards with those of Descartes, Dr. Grew, and Mr. Morton, I find I have but little to add on the subject; yet, as I observed the progress of nature, in this sort of crystallisation, with a great deal of pleasure, I hope it will not be disagreeable to you to receive an account of it.

I shall begin with the

most simple figures A

and B, of which the BA

former is a roundish

pellet of ice; the se

cond, a small oblong

body, with parallel sides,

F

which is often as fine as a hair. Of this latter kind the flakes of snow chiefly consist; and though they look white to the eye, yet when viewed with a small magnifier of a microscope, they appear like so many transparent needles of ice thrown together, without any order.