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morning : which though he hiinself saw not, was yet there observed by several persons, who made various reports of it; but the more intelligent agreed that it was seen descending in the north, and left behind it a long white streak where it had passed. At the same time, at Haarburg, the like appearance was seen in the N. E. or rather N.N.E.; as also at Hamburg, Lubec, and Stralsund, all which are about forty German miles from Leipsic: but in all these places, by persons unacquainted with the manner of properly describing things of this kind. So that all we can conclude from it is, that this meteor was exceedingly high above the earth, as well as the former.

All the circumstances of these phænomena agree with what was seen in Eugland, in 1708 ; but it commonly so happens, that these contingent appearauces escape the eyes of those that are best qua. lified to give a good account of them. It is plain, however, that this sort of luminous vapour, is not exceedingly seldom thus collected; and when the like shall again happen, the curious are entreated to take niore notice of them ihan has been hitherto done, that we may be enabled the better to account for the surprising appearances of this sort of meteor.

[Phil. Trans. 1714.

SECTION III.

Extraordinary Blazing Meteor, seen all over England, March

19, 1718-19.

By the same. This wonderful luminous meteor, which was seen in the heavens on the 19th of March, as it was piatter of surprise and astonisbment to the vulgar spectator, so it afforded no less subject of inquiry and entertainment to the speculative and curious in physical matters; some of its phænomena being exceedingly hard to account for, according to the notions hitherto received by our naturalists; such are the very great height thereof above the earth, the vast quantity of its matter, the extreme velocity with which it moved, and the prodigious explosions beard at so great a distance, whose sound, attended with a very sensible tremour of the subject air,

was certainly propagated through a medium extremely rare, and next to a vacuum.

In No. 341 of these Transactions, I have collected what I could find of such meteors; and since, turuing over the Ephemerides of Kepler, I accidentally hit upon another, prior to all those there described, and which was seen all over Germany, Nov. 7,0. S. 1623, and in Austria also was heard to burst with an explosion like thun. der. Yet neither this, nor any of the other hitherto described, seem to come up in any circumstance to this late appearance; of which I am in hopes to give a satisfactory account, being enabled thereto by the numerous accounts communicated to the Royal Society from most parts of the kingdom. Some of the most per. fect descriptions we have received are the following.

First, our very worthy vice president, Sir Hans Sloane, being abroad at that time, happened to have his eyes turned towards it, at its very first eruption; of which he gave the following account: that walking in the streets in London, at about a quarter after eight at night, he was surprised to see a sudden great light, far exceed. ing that of the moon, which shone very bright. He turned to the westward, where the light was, which he apprehended at first to be artificial fire works, or rockets. The first place be observed it in, was about the Pleiades northerly; whence it moved after the man. ner of a falling star, but more slowly, in a seeming direct line, de. scending a little beyond and below the stars in Orion's Belt, then in the S.W. The long streain appeared to be branched about the middle, and the meteor in its way turned pear. fashioned, or taper. ing upwards. At the lower end it came at last to be larger and spherical, though it was not so large as the full moon. Its colour was whitish, with an eye of blue, of a most vivid dazzling lustre, which seemed in brightness very nearly to resemble, if not surpass, that of the body of the sun in a clear day. This brightness obliged him to turu his eyes several times from it, as well when it was a stream, as when it was pear-fashioned and a globe. It seemed to move in about half a minute, or less, about the length of 20€, and to go out about as much above the horizon. There was left be. hind it, where it had passed, a track of a cloudy or faint reddish yellow colour, such as red-hot irou or glowing coals have, which continued more than a minute, seemed to sparkle, and kept its place without falling. This tract was interrupted, or had a chasm. VOL. IV.

2

towards its upper end, at about two-thirds of its length. He did not liear any noise it made ; but the place where the globe of light had been, continued for some time after it was extinct, of the same reddish yeHow colour with the stream, and at first some sparks seemed to issue from it, such as come from red-hot iron beated out on an anvil.

All the other accounts of the phenomenon, in London, agree is this, that the splendour was little inferior to that of the sun; that within doors the candles gave no' manner of light, and in the streets not only all the stars disappeared, but the moon, then nine days old, and high near the meridian, the sky being very clear, was s6 far effaced as to be scarcely seen; at least not to cast a shade, even where the beams of the meteor were intercepted by the houses; so that for some few seconds of time, in all respects resembled perfect day.

The time when this happened was generally reckoned at a quarter past eight; but by the more accurate account of the Rev. Mr. Pound, who only saw the light, agreeing with what has been sent us from the Parisian observatory, it appears to have been at eight hours eight minutes apparent time at London. And the sun being then in glo of Aries, the right ascension of the mid-heaven was 130° 45', by which the position of the sphere of fixed stars is given. Hence the lucida pleiadum will be found at that time to have been 254° high, in an azimuth 6° to the northward of the west ; and consequently the arch the meteor moved in, was inclined to the horizon with an angle of about 27°, having its node or intersection with it, pearly south-south-west, as will be more evident by what follows.

At Oxford, five minutes earlier, Mr. John Whiteside, R. S. Soc. Keeper of the Ashmolean Museum, and very skilful in both matbematical and physical matters, immediately after the extinction of the meteor, made haste out to see what it might be; and well con. sidering the situation of the track it had left in the sky, found it to have passed about 11° above the preceding shoulder of Orion, and about 34° above the middle of his Belt, where there appeared a Juminous nubecula of a reddish light, being a dilation of the track, seeming to have been occasioned by some explosion there; and by what he could learn from those that saw it, it was thereabout that it broke out, and first began to efface the stars. Hence it proceeded as to sense, in an arch of a great circle ; and passing in the middle between the tail of Lepus, Bayer's 0 and ß in the fore-foot of Canis Major, it terminated about & in the breast of the same, nearly in 95° of right ascension, with 23° south declination; and at the place of its extinction there remained a large whitish nebula, much broader, and of a stronger light, than the rest of the track, which he took for a certain indication of a very great explosion made there. By computation, it will be found that the angle this track made with the horizon of Oxford was nearly 40°, and its intersection due S. S.W.; and that the place of its extinction was about go above the horizon in the azimuth of 32° to the west.

At Worcester, Mr. Nicolas Fatio, a person greatly skilled in astrouomical affairs, saw this meteor descend obliquely towards the south, making an angle with the horizon of about 65°, and intersecting it about S. S.W. Į S. The track left all Orion and Canis Major to the westward, and divided the distance between Sirius and Procyon, so as to be almost twice as far from Procyon as Sirius. The time here was one minute before eight, this city being about nine mi. nutes of time to the west of London, and consequently the right ascension of the mid-heaven 1284 degrees.

Now the situation of the three cities, London, Oxford, and Worcester, being nearly on the same W.N.W. point, on which the track of the meteor had its greatest altitude above the horizon, equal to the angle of its visible way; if we suppose it at London to have been 27 degrees high, and at the same time at Worcester to be 65 degrees high, in the plane of the vertical circle passing through London and Worcester; supposing likewise the distance between them to be 90 geographical miles, or one degree and a half of an arch of a great circle of the earth, we shall, by an easy trigonometrical calculus, find the perpendicular height to have been 64 such miles; and the point over which it was then perpendicular to have been 30 such miles W.N.W. from Worcester; and the geographical mile to the English statute mile being nearly as 23 to 20, this height will be no less than 78 English miles; the place directly under it will be found to be about Presteign, on the confines of Hereford and Radnorshires. The Oxford observation nearly agrees in the same conclusion,

This altitude being added to the semidiameter of the earth as radius, becomes the secant of 11 degrees: so that the meteor might be seen above the horizon, in all places not more than 220 leagues distant from it. Whence it will not be strange that it should be seen over all parts of the islands of Great Britain and Ireland, over all Holland, and the hither parts of Germany, France, and Spain, at one and the same instant of time.

This suggests a cousiderable use that might be made of these momentaneous phænomena, for determining the geographical longitudes of places. For if, in any two places, two observers, by help of pendulum elocks duly corrected by eelestial observation, exactly note at what hour, minute, and second, such a meteor as this ex. plodes and is extinguished, the difference of those tiines will be the difference of longitude of the two places, as is well known.

Having thus fixed one point in the line of its motion, let us now consider what course the meteor took from thence. And first at the town of Kirby Stephen, on the borders of Yorkshire and Westmoreland, in a meridian very little to the westward of Worcester, but about two degrees and a half more to the north, it was observed to break out as from a dusky cloud, directly under the moon, and from thence to descend, nearly in a perpendicular, almost to the horizon. Now the moon, being at that tine in the third degree of Len, was about half an hour past the meridian, and consequently much about a point to the west, or S. by W.: and the situation of Presteign from Kirby-Steven being sufficiently near on the same point, it follows that the direction of the track of the meteor was according to the great circle passing over those two places.

And this is further confirmed by the observation of Sam. Cruwys, Esq. Reg. S. S. who at Tiverton, about twelve geographical miles nearly due north from Exeter, observed the first explosion of this meteor exactly in his zenith, as he was assured by applying his eye to the side of his door, which he took to be perpendicular, and looking upwards : and from thence he saw it descend to the south. ward, directly in the same azimuth, without declining either to the right or left. Hence it is plain, that the track likewise passed over this place, which by our best maps is found to lie in a line with Presteign and Kirby-Steven; so that we shall take it for granted that this was the very course it beld.

On this supposition, that the first explosion, attended with the reddish nubecula, was directly over Tiverton, we have the Oxford

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