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and altitudes are readily deduced. And let those who contend for a much less beight of this meteor, try if they can, on such their supposition, to reconcile the several phænomena with one another, and with the observation of the Rev. Mr. William Ella, rector of Rampton in Nottinghamshire, between Gainsborough and Redford, which for its exactness I must not omit. Here, at 8h. 5m. the meteor was seen to pass precisely in the middle between Sirius and the fore foot of Canis Major, moving obliquely to the southward, in a line whose direction seemed to be from the middle between the two shoulders of Orion; the latitude of the place being nearly 53° 20', and long. west from London 0° 45'. Let them try host they can account for its being seen five degrees high at Aberdeen in Scotland, and near as much at Peterhead, half a degree more northerly: and then they will be better able to judge wbether it did not exceed the reputed limits of our atmosphere. Lastly, if the apparent altitude of the meteor at Paris was not five degrees and a half, but eleven, on the W. by N. point, when it must bave been in its greatest lustre, there will be no pretence to bring it lower than I bave nade it; especially if it be allowed to have followed the track I have assigoed it, over Presteigu, Cardiff, Minehead, Tiverton, and Brest in Bres tany.

Allowing this to have been the path it moved in, it would be easy to assign the real magnitude and velocity of this meteor, if the several accounts of its apparent diameter, and of the time of its passage from one of its explosions to the other, were consistent among

themselves. But some of them making its visible appearance nearly equal to the sun's, which in the opinion of many it far ex. ceeded, we may suppose with the least that, at the time when it first broke out over Tiverton, its diameter was half a degree; and its horizontal distance being 150 geographical miles from London, and its altitude 60, the hypothenusal, or real distance from the eye, will be more than 160 such miles; to which radius ibe subtense of balf a degree will be above an English mile and half, being about 2800 yards nearly. After the same manner it is difficult to assign its due velocity, while some make it half, others less than a quarter, of a minute, in passing from its first explosion to its last extinction : but the distance it moved in that time being about three degrees, or 180 geographical miles, we may modestly compute it to have run above 300 such miles in a minute ; which is a swiftness wholly incredible;

and such, that if a heavy body were projected horizontally with the same, it would not descend by its gravity to the earth, but would rather By off, and move round its centre in a perpetual orbit like that of the moon.

Of several accidents that were reported to have attended its pase sage, some were the effect of pure fancy; such as the hearing it hiss as it went along, as if it had been very near at hand; some imagined they felt the warmth of its beams; and others thought they were scalded by it. But what is certain, and no way to be disputed, is the wonderful noise that followed its explosion. All accounts from Devon and Cornwall, and the neighbouring counties, are unanimous, that there was heard there, as it were, the report of a very great cannon, or rather of a broadside, at some distance, which was soon followed by a rattling noise, as if many small-arms had been promis. cuously discharged. What was peculiar to this sound 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 them. selves, 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 yet know the extent of this prodigious sound, which was heard, against the then easterly wind, in the neighbourhood of Lon. don; and by the learned Dr. Tabor, who distinctly heard it beyond Lewes in Sussex : so that I cannot help thinking, that such a me. teor as this might have occasioned that famous ode of Horace : Parcus deorum cultor, &c.

Namque Diespiter
Igni corusco nubila dividens,
Plerumque; per purum tonantes

Egit equos volucremque currum,
Quo bruta tellus, &c. Concutitur.

But whether the report heard near Lewes was of that explosion right over Devonshire, or rather of that latter, and much greater at the extinction over Bretany, I shall not undertake to determine, till we have some further accouuts from France, and inore satisfactory information to build upon. It remains to attempt something towards a solution of the uns common phænomena of this meteor; and by comparing them with things more familiar to us, to shew at least how they might possibly be effected. Aud first, the unusual and continued heats of the last summer in these parts of the world, may well be supposed to have excited an extraordinary quantity of vapour of all sorts; of which the aqueous, and most others, soon condensed by cold, and wanting a certain degree of specific gravity in the air to buoy them up, ascend but to a small height, and are quickly returned in rain, dews, &c. whereas the inflammable sulphurous vapours, by an innate levity, have a sort of vis centrifuga, and not only have no need of the air to support them, but being agitated by heat, will ascend in vacuo Boileano, and sublime to the top of the receiver, when most other fumes fall instantly down, and lie like water at the bottom. By this we may comprehend how the matter of the meteor might have been raised from a large tract of the earth's surface, and as. cend far above the reputed limits of the atmosphere ; where, being disengaged from all other particles, by that principle of nature that congregates homogenia, visible in so many instances, its atoms might in length of time coalesce and run together, as we see salts shoot in water, and gradually contracting thenuselves into a narrower com. pass, might lie like a train of gunpowder in the ether, till catching fire by some internal ferment, as we find the damps in mines frequently do, the flame would be communicated to its continued parts, and so run on like a train fired.

This may explain how it came to move with so ipconceivable a ve. locity: for, if a continued train of powder were no larger than a barrel, it is not easy to say how very fast the fire would fly along it; much less can we imagine the rapidity of the ascension of these inore inflammable vapours, lying in a train of so vast a thickness. If this were the case, as it is highly probable, it was not a globe of fire that ran along, but a successive kiudling of new matter : and as some parts of the earth might emit these vapours more copiously than others, this trajo might, in some parts thereof, be much denser and larger than in others, which might occasion several smaller explosions, as the fire ran along it, besides the great ones, which were like the blowing up of magazines. Thus we may account for the rattling noise like small-arms, heard after the great bounce ou the explosion over Tiverton; the continuance of which, for some time, argues that its sound came from distances that increased.

What may be said to the propagation of the sound through a medium, according to the received theory of the air above 300,000 times rarer than what we breathe, and next to a vacuum, I must confess I know not. Hitherto we have concluded the air to be the vehicle of sound; and in our artificial vacuum we fiud it greatly diminished : but we have this only instance of the effect of an ex. plosion of a mile or two diameter, the immensity of which may perlaps compensate for the extreme tenuity of the medium.

[Phil. Trans, 1719.

SECTION 19.

Meteor of a Flaming Sword, seen in Yorkshire, and other

neighbouring Counties, May 18, 1710.

By Mr. Ralph Thoresby. A STRANGE meteor was seen at Leeds, on Holy Thursday, 1710, which the common people call a faining sword. It was seen in the neighbouring towns, but a great way north, as also above fifty miles south of Leeds. It appeared here at a quarter past ten at night, and took its course from south to north: it was broad at one end, and small at the other; and was by some thought to re. semble a trumpet, and moved with the broad end foremost. The lighit was so sudden and bright, that people were startled to see their own shadows, whev neither suv nor moon shone

them. This is remarkable, that all persons, though at many miles dis. tance from each other, when they saw it, thought it fell within three or four furlongs of thein, and that it went out with bright sparklings at the small end. An ingenivus clergyman told me, that it was the strangest deceptio visus he was ever sensible of, if it was not absolutely extinguished within a few paces of him; and yet others saw it many miles off, further nortlı, in a few moments. It was likewise seen in the counties of Nottingham and Derby, as well as those of York and Lancaster.

upon

[Ibid. 1711.

SECTION V.

Luminous Meteor, seen at Peckham, Dec. 11, 1741.

By Thomas Milner, M.D.

Dec. 11, 1741, at seven minutes past one in the afternoon, a • globe of light, somewhat larger thau tlie horizontal full moon, and

as bright as the moon appears at any time while the sun is above the horizon, instantaneously appeared, in a clear blue sky, about the S.S.E. moving towards the east with a continual equable motiou, and leaving behind it a narrow streak of light, whiter than the globe itself, throughout its whole course. Towards the end it appeared less than at the beginning of its motion; and within three, or at most four, seconds, it suddenly vanished. Its apparent velocity was nearly equal to balf the medium velocity of those usual meteors commonly called falling or shooting stars.

The narrow luminous streak remained very distinct after the globe was gone; and gave a fair opportunity for taking the elevation of this phenomenon above the horizon, at the beginning and end of its motion, &c. which was found to be twenty degrees. This lumi. nous track, or path, seemed a right line, not quite parallel, but a little inclined to the plane of the horizon, viz, highest towards the east. It was at first very narrow, and pointed at each extremity; but soon grew broader, and within twenty minutes after the appearance, it was exactly like a long bright rare cloud, discontinued in two places, above three times its first breadth, and a little more inclined to, and elevated above, the horizon, than it was immediately after the motion of the globe.

[Phil. Trans. 1749.

SECTION VI.

Account of some late Fiery Meteors, with Observations.

By Charles Blagden, M.D. Sec. R. S.

This account respects chiefly the two most remarkable of the meteors that had lately appeared, and is founded partly on private conimunications, and paytly on such accounts as were publisbed in

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