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found that all my former observations were very just and true; viz. that sound moves a mile in 9 half seconds and 1, two miles in 18 and }, and three miles in 27 half seconds and *, and so on.
I caused guns to be fired every half hour, from six in the evening till midnight, and found the report always reach the ear, without any remarkable variation, in 120 or 122 half seconds of time, though the wind was directly against it; but at other times, when the wind was favourable, and blew either direct, transversely, or obliquely: on observing the report of the same guns reach in 111, 112, 113, 114, 115, 116, or at most in 117 half seconds of time, I was at length assured, that some real difference caused this variety in the observations. And not only do winds with or against the sound accelerate or retard its motion, but likewise according to the various degrees of their strength and weakness, is the sound more or less promoted or impeded; of which I made particular observations.
The greatest difference I have observed in the motion of sound in the space of about 13 miles, was about 9 or 10 half seconds, when a strong wind promotes, and only a gentle wind impedes it; but when only a gentle wind, or almost none at all, opposes or favours the sound, the difference hardly exceeds two or three half seconds.
To discover the quantity of space that winds pass over in any given time, I took some light bodies, such as down, &c. and from the several experiments I made with these, when the strength of the wind was different, found that the strongest wind scarcely passed over 60 miles in an hour; for instance, on August 11. 1705, the violence of the wind was such, as almost to beat down a windmill, near the place where I made
my observations; and estimating by the numeral characters, 0, 1, 2, 3, 4, 5, 6, to 10, 15, or more degrees, the strength of winds, the strength of this I reckoned at about 12 or 14 of these degrees; and from repeated experiments I found, that that hurricane passed over about 33 feet in a half second of time, or 45 miles in an hour; whence I conclude, that in the most violent storms, not excepting that in Nov. 1703, the wind does not traverse above 50 or 60 miles in an hour.
Having thus determined the velocity of rapid winds, we may from hence more easily conjecture the velocity of such as are less so; and I have found from several experiments, that some of them move 15 miles, others 13, some more and some fewer, in an hour; and that others again have so slow a motion, as scarcely to pass over one mile in an hour: also
some are so slow, that a person, walking or riding, may easily outrun them, as is apparent to sense.
From what has been said above, I firmly conclude, that sound is propagated with this degree of velocity, viz. that in 9 half seconds and ļ it moves the space of a mile, or 5280 English feet; or, which is the same thing, 571 feet in a half second of time, or 1142 feet in a whole second. Thus, sound moves through the above space, if the flux of the atmosphere or wind be transverse or across, and is its mean motion ; but should the wind increase the rapidity of sound, it is possible that it may move upwards of 600 feet in a half second of time; or, on the contrary, should it retard sound, it may move not above 560 feet in the same time.
A new Island raised near Sant-Erini, in the Archipelago. By
Dr. W. SHERARD, Consul at Smyrna. — [1708.] On the 12th of May, 1707, an island began to rise up, a musket-shot distant from the island of Sant-Ěrini, which continually increasing from day to day in the same manner, and troubling the sea, there rose up several rocks, that fixed themselves to this island; so that now, June 21., it is about half a mile in circumference.
Constantinople, Jan. 4. 1708. - They write from the island of Sant-Erini, in the Archipelago, about 28 leagues north of the town of Candia, that there lately sprung up from the bottom of the sea an island, formed of stones cast up by a volcano, which has often produced the same effects, and after the same manner, In the year 726, in the time of the Emperor Leo Isauricus, an island was formed on the north side, called the Burnt Island, by matter thrown up and heaped together by this volcano. In 1427, in the month of December, this Burnt Island was increased by huge rocks cast up by subterraneous fires. In 1650, in the month of September, the volcano again took fire, and produced the same effects, without forming any island, but only a shelf or bank 10 fathoms under water. Lastly, in the month of November last, 1707, the volcano made an island, which is already two miles in circum. ference, and still increases by rocks and other new matter thrown up. This burning was preceded, as at all other times, by violent shakings of the earth, followed by a thick smoke, that rose out of the sea in the day-time, and by flames in the night, and accompanied with a terrible roaring under ground. There is no instance of the effects of any volcano at land, like these in the sea ; and yet what renders them the mor
credible, is, that the island of Sant-Erini itself is almost all of it composed of burnt rocks and pumice-stones: it produces some sorts of grain, but has neither rivers nor springs, nor any other water but what is saved in cisterns.
Microscopical Observations on the Tongue and Taste. By
Mr. Anthony Van LEUWENHOEK. [1708.] Having taken some neats' tongues, and separated some thin parts of the outer skin, where I conceive is the place that admits the juices into the tongue, by which that sensation is produced which we call the taste, I separated those aforesaid external particles as well as I could from those that lay under them, and observed that the latter, that is, the internal, were furnished with a multitude of pointed particles, the tops of which were mostly broken off
, and remained sticking in the outer skin : and one of those internal particles of the tongue, before a microscope, appeared as a transparent body, something larger than a thimble, having small internal holes or cavities, through which a greater quantity of light was admitted than by the other parts ; and it seemed that the extreme parts of those cavities had exceedingly small orifices in them. On viewing with a microscope that space of the tongue which is between the protuberances, it was all over covered with abundance of exceedingly small rising round particles, so close to each other, that you could not put in two hairs between them. I stripped off also the surface of the tongue with a sharp knife, and repeated the same a second time, and then discovered an unspeakable number of small holes, some of which seemed to be filled, others were cut through lengthwise. From this appearance I inferred, that when we press our tongues against the roof of the mouth, in order to taste any thing, the said long particles, the ends of which are exceedingly slender, press through the uppermost skin, which at that place is also very thin, and endued with small pores or holes, and so receives a little juice; from all which proceeds the kind of sensation which we call taste.
I had often thought that our taste proceeds alone from the tongue, but within these few days I am become of another opinion ; for when I viewed that part of the roof of the mouth, opposite to the top of the throat, where the notched or jagged parts of the tongue are determined, I judged that to be the place from whence the head partly discharges itself, and the matter to be cast out, which comes into the mouth without its proceeding from the lungs; as also that there are a great many parts in it, which receive the matter which we call the taste.
I took a cow or ox's head, and cut out the roof or palate, close to the throat, while yet warm ; and pressing it gently, I could perceive issue out of several parts of it, small
, round, protuberant, transparent drops ; and pressing it a little harder, there ensued a yellow moisture. I took the uppermost skin of the said part, and viewing it through a microscope, I observed, that at most of the places from which the said liquor proceeded, there was a round ring or circle, of rather a darker colour than the skin or membrane that lay next it ; I could also perceive in some of the said places, out of which the liquor camę, that there were small holes or orifices, and these moist places were not all at equal distance from each other.
I discovered, also, in the said skin or membrane, a vast number of exceedingly small protuberances; as also in the uppermost thin skin, holes so very small, that they almost escaped the view through a microscope. On viewing the rough skin that lay under the thin skin, I perceived such slender fibres or bristles, of a darkish colour, that passed straight through the said skin, corresponding with the small protuberances and little holes, discovered in the uppermost skin. From this observation I imagined, that the last-mentioned holes or orifices, and the little fibres which I saw in the thick rough part, were those long particles that receive the juices, and which also produce that sensation called taste.
I also discovered several long slender pointed particles, which I conceived to be rooted or planted in the skin with a pointed end, and that these caused the afore-mentioned protuberances. And as these pointed parts, which were fixed in the said protuberances, were opposed to the sight with the points uppermost, one could not easily make any
observation of them.
I was desirous to search into the inward parts of the nostrils of an ox, as well as I was able, with a view to the organs of smell ; in doing which, I saw that each side of the mouth, which one might call the lips, was furnished with a great many pointed parts, that were very thick in the inner skin, and being round ran into a very slender point. I likewise observed the skin of several of the said parts, which were very strongly united to the parts that lay in it; and found that one of those parts that lay within, consisted of a great many pointed particles, which were much thicker and longer than those I had discovered in the inward parts of the tongue.
The new Island thrown up near the Island of Santerini. By
Mons. BOURGIGNON. - [1708.] On Monday the 23d of May, 1707, at sun-rising, we observed between the two Burnt Islands, commonly called the Little and Great Cameny, as it were a floating rock; which we thought at first had been some vessel shipwrecked on that coast, and seemed as if it would in a little time be dashed to pieces against the Lesser Cameny, that was hard by; on which account some mariners, in hopes of booty, put out immediately to view it. Soon after we were surprised to hear by them, that it was a shoal, which began to spring up
from the bottom of the sea, and was not as yet very plainly to be discerned. Next day several persons went out of curiosity to satisfy themselves. Some of them went upon this new shoal, which was still moving, and sensibly increased under their feet. They brought back several curiosities, and among others a kind of oysters, very large, and of an exquisite taste, which they found sticking to the rock, and raised out of the water, as the shoal had increased in height; also a remarkable fine pumice-stone.
Two days before the springing up of this shoal there was an earthquake over the whole island ; and this was the only trouble and fear that this new island gave us ; for from its first appearance to the 13th or 14th of June it has continually increased very sensibly, both in extent and height, being now about half a mile in circuit, and from 20 to 25 feet high. This shoal is very pleasant
to the view, being of a white colour, and round figure. The earth composing it is light, with a small mixture of clay. The sea appears now more and more troubled every day; not so much by this shoal lately removed, and still foating, as on account of the mixture of a vast quantity of different matters, continually thrown up night and day from the bottom of the sea; so that one might easily distinguish several sorts of minerals, by the diversity of colours they made on the surface of the water ; but sulphur was in the greatest abundance, insomuch that the sea was coloured with it about Santerini, to near 20 miles' distance. The excessive rolling of the waves about the new shoal was greater than ever, and a more than ordinary heat was sensible to any one that approached too near, which was doubtless the cause of such quantities of fish being found dead on the shore.