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Fiery Meteors, with Balls that have descended to the Earth*.
1. Account of a fiery Meteor seen, at Jamaica, to strike into
By Mr. Henry Barham, F.R.S. About the year 1700, as I was riding one morning about three miles north-west from St. Jago de la Vega, I saw a ball of tire, appearing to me of the size of a bomb-shell, swiftly falling down with a great blaze. When I arrived where it fell, I found the peo. ple wondering at the ground being broken in by a ball of fire, which they said fell down there. I observed there were many holes in the ground; one in the middle, of the size of a man's head, and five or six smaller holes round about it, of the size of a man's fist; and so deep, especially the largest, as not to be fathomed by what long sticks they had at hand. It was observed, that the green grass was perfectly burnt near the holes, and a strong smell of sulphur remained thereabouts for a good while after.
We had a very rainy night before, with much lightuing and thunder, which is frequent in Jamaica, often killing cattle in the fields. These claps are much louder and stronger than any in Europe, aud our showers of rain are also more violent. We have lightning all the year round; but our great raios are in the inonths of May, August, and October.
Our island is full of mines, and, I question not, very rich. It is very subject to earthquakes; several happening every year, especially after great rains, which fill up all the great cracks in the surface of the eartı: for in a very dry time, they are so very large, deep, and gaping so open and wide, that it is dangerous to ride over some parts of the Savannas, for fear a horse should get his legs into them. Our earthquakes make a noise or rumbling in the earth, before we feel the shake; and seem to run swiftly to the westward.
[Phil. Trans. 1718.
* See for other instances, chap. xliii. sect. iv.
2. Ball of Sulphur supposed to be generated in the Air.
By Mr. Benjamin Cooke, F.R.S.
The great heats we have lately suffered were ushered in by a very gloomy night, of almost continual lightning, accompanied with very loud claps of thunder; which, as usual, were towards the morning followed by very beavy showers of rain. Early next day, in a meadow near the sea-shore, far from any house, and where it has not been known that any improvement has been carried on, a hus. bandman found a beautiful yellow ball lying on the turf. It proved to be of sulphur, of which it smelt uncommonly strong. It was frosted, as it were, all over with an efflorescence of fine, shining, yellowish crystals, which soon fell off with the lightest toucb.
It has on one side a deep hole, admitting the end of a middle. sized knitting-needle ; and on the opposite side a deep depression, which would induce one almost to think its form had been at first nearly spheroidal, formed by a revolution round a supposed axis connecting those two parts. It has several other boles scattered irregularly up and down its whole surface, some fit to admit a hog's bristle, others a hair; as if it had been made of a fine powder, and some liquid, and after mixing had suffered some fermentation ; but those parts of it which are solid, seem more compact than those of the common roll brimstone of the shops, and the powder of it burns with a wbiter flame, and less acid fumes. Its longest diameter is between eight and nine, and its shortest betwixt six and seven tenths of an inch ; its weight is 108 grains.
We find frequent mention, in the description of thunder-storms in hot climates, that there falls often a flaming bituminous matter to the ground, which sometimes burns not to be soon extinguished; but more frequently spatters into an infinite number of fiery sparks, doing great damage where they strike, always attended with a sulphurous suffocating smell, commonly compared to that of gunpowder.
Whether this sulphurous ball was intended for one of these, but by some accident missed firing, it is now time to consider. Had it been formed in the earth, how should it get to the surface, without losing that most elegant frosty covering of fine shining crystals, and
appear not in the least sullied, or its pores filled with earth, or other terrestrial matter ? on the contrary, not the least adhesion of any thing of that kind can be observed : besides, brimstone made the ordinary way seems to have a different texture of its internal parts, from this ball. From these observations Mr. Cooke concludes it not formed in the earth.
3. Fire-ball accompanied with a shower of Stones from the
Atmosphere. C. Bior, member of the National Institute, in a letter to the French Minister of the Interior, dated July 20, 1813, gives a detailed account of his inquiries, &c. respecting a fire-ball which exploded in the neighbourhood of Laigle.
On Tuesday, April 26, 1812, about one in the afternoon, the weather being serene, there was observed from Caen, Pont Aude. mer, and the environs of Al nçon, Falaise, and Verneuil, a fiery globe of a very brilliant splendour, which moved in the atmosphere with great rapidity.
Some moments after there was heard at Laigle, and in the envi. virons of that city, in the extent of more than thirty leagues in every direction, a violent explosion, which lasted five or six minutes.
At first there were three or four reports like those of a cannon, followed by a kind of discharge which resembled a firing of mus. ketry; after which there was heard a dreadful rumbling, like the beating of a drum. The air was calm and the sky serene, except a few cloods, such as are frequently observed.
The noise proceeded from a small cloud which had a rectangular form, the largest side being in a direction from east to west. It appeared motionless all the time that the phenomenon lasted. But the vapour of which it was composed was projected momentarily from the different sides by the effect of the successive explosions. This cloud was about half a league to the north-north-east of the town of Laigle; it was at a great elevation in the atmosphere, for the inhabitants of two hamlets, a league distant from each other, saw it at the same time above their heads. In the whole canton over which this cloud hovered, a kissing noise like that of a stone discharged from a sling was heard; and a multitude of mineral måsses, exactly similar to those distinguished by the name of meto oric stones, were seen to fall at the same time.
The district, in which the stone fell, forms an elliptical extent of about two leagues and a half in length, and nearly one in breadth ; the greatest dimension being in a direction from south-east to north west, forming a declination of about 20°. This direction which the nieteor must have followed is exactly that of the magnetic meridian; which is a remarkable result
.. The largest of these stones fell at the south-east extremity of the large axis of the ellipse; the middle.sized ones fell in the centre, and the smallest at the other extremity. It thereby appears that the largest fell first, as might naturally be supposed.
The largest of all those which fell weighs 17 pounds. The smallest he saw weighed about two gros, which is the thousandth part of the former. The number that fell is certainly abode twoor three thousand. They were friable some days after their fall, and smelled strongly of sulphur. Their present hardoess was acquired gradually.
Observations on Fire Balls.
By F. C. Falda.
Notwithstanding the great progress which the sciences have made in the present century; and though our knowledge of the atmosphere bas, in particular, been much enlarged; we are still far from being able to explain all its phænomena, especially those of the luminous kind, in a manner sufficiently satisfactory to the cautious and reflecting philosopher. Though many, in consequence of the im. portant discoveries made respecting the electricity of the clouds, imagine that they have found in the electric fluid, so widely diffused, a certain key to all distant phænomena of a similar kind; yet the greater part of them as mere observations, and the explanations given of them as mere hypotheses, must be left to the decision of posterity. It would be useless, and perhaps it is impossible, to mention all these phænomena in any certain order: but the most
singular of them are large fire-balls (bolides), which, on account of their importance in natural philosophy, have in modern times ex. cited universal attention *.
Respecting the origin and nature of these phænomena, which are but seldom seen, and always surprise us as it were accidentaly, we can venture conjectures and explanations only when we have com. pared a series of observations carefully made with the circumstances by which they were attended, and have then deduced from them general conclusion i t, which in the hands of the mathematician may conduct with the greatest certainty to a knowledge of their nature, and of the causes by which they are produced. I shall endeavour, therefore, to present the reader with such conclusions drawn from a series of observations made in regard to fire-balls, not with the iotention of giving any explanation from them myself, but in compli. ance with the excellent rule laid down by Le Roy, when he says, speaking of this circumstance : “Let us always collect observations without being too forward to deduce consequences from them, and to explain phænomena respecting which we have at present so little knowledge 1."
* On the 13th of July, 1797, about 42 minutes after nine in the evening, I had the good fortune, when in company with several of my friends, to see a meteor of this kind. It appeared in the southern part of the horizon, at the height of 8 or 10 degrees; had the form of a perfect globe or sphere well de fined at the edges, almost as large as the moon when at full, and proceeded in the space of scarcely a second, while its course was only marked by a fine white streak of light, in an almost perpendicular direction towards our horizon, which was confined by houses, and disappeared behind them. Its colour and splendour near the middle were sometimes of a dazzling white. The heat during the day, and in the evening, was considerable. The thermometer varied from 18 to 20 of Reaumur, and between the hours of four and five in the afternoon there had been a storm in the same quarter of tbe heavens. At the surface of the earth there was a perfect calm, and in the evening the weather-cocks shewed that a light south-west wind prevailed at some beight in the atmosphere. At the time of this phenomenon the earth was overspread by a pale mist, through which no stars could be perceived, and which the following night became a thick fog.
+ Il faudroit etudier avec soin les rapports de ces phénomenes avec les autres phénomènes atmosphériques ; rechercher l'état du ciel avant et aprés leur apparition, déterminer les tems, les circonstances, et lieux, ou ils sont les plus communs, savoir pourquoi ils sont rares, et pourquoi ils arrivent. Que d'observations 6 faire ! Que d'observateurs à occuper !--Sennebier.
Memoires de l'Academie des Sciences, 1771.