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nearly in the same proportion as the globular substances. But it will be necessary to exhibit a specimen of some of the analyses, as published by the philosophers to whom we are indebted for them. A stone which fell at Benares in India was analysed by Howard. The pyrites consisted of

2.0 sulphur
10.5 iron

1:0 nickel
2.0 earths and foreign bodies

15:5

The spherical bodies 50.0 silica

15.0 magnesia
34.0 oxide of iron
2.5 oxide of nickel

101.5

The eartlıy cement 48.0 silica

18.0 magnesia
34.0 oxide of iron
2.5 oxide of nickel

102.5

A stone which fell in Yorkshire, deprived as much as possible of its metallic particles, gave Mr. Howard from

150 grains, ..... 75 silica

37 magnesia
48 oxide of iron
2 oxide of nickel

162

The increase of weight was owing to the oxidizement of the metal. lic bodies.

Stones which fell at Laigle in France, in 1803, yielded, by the analyses of Vauqueliu and Fourcroy,

54 silica
36 oxide of iron
9 waglesia
3 oxide of nickel
2 sulphur
I live

105

The following Table exliibits the result of the most remarkable analyses of such stones, which bave been made since the publication of Howard's paper on the subject.

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5. The experiments of Ioward, thus confirmed by others, and supported by the most respectable historical evidence, having de. monstrated that these stony bodies really do fall from the heavens, it was natural to expect that various attempts would be made to accouut for their appearance. But such is the obscurity of the subject, so litile progress have we made in the science of meteorology, that no opinion in the slightest degree probable lias hitherto

Phil. Mag. xvi. 302. + Vauquelin, Phil. Mag. xvi. 302. The stone fell at Ensisheim, in 1492.

Klaproth, Gehlen's Jour. i. 8. The stone fell at Sienna, in 1794.
Klaproth Ibid. p. 19. The stone fell at Anchstadtschen, in Germany.

Laugier, luid iv. 331. The stone fell at Vaucluse in 1804. See a description of it by Vauquelin, Ann. de Chim. xlviii. 225.

Proust, Jour. de Phys. Ix. 185. The stone fell at Sigena, in 1773.

been advanced. It was first supposed that the bodies in question had been thrown out of volcanoes; but the immeuse distance from all volcanoes at which they have been found, and the absence of all similar stones from volcanic productions, render this opinion untenable. Cbladni endeavoured to prove that the meteors from which they fell were bodies foating in space, unconnected with auy planetary system, attracted by the earth in their progress, and kindled by their rapid motion through the atmosphere. But this opinion is not susceptible of any direct evidence, and can scarcely be believed, one would think, even by Dr. Chladni binself. La Place suggests the probability of their having been throwo off by the volcanoes of the moon : But the meteors wbich almost always ac. company them, and the swittuess of their horizontal motion, militate too strongly against this opinion. The greatest number of philosopbers consider them, with Mr. King and Sir William Hannil. ton, as concretions actually formed in the atmosphere. This opinion is undoubtedly the most pro able of all; but in the present state of our knowledge, it would be absurd to attempt any explanation of the manner in which they are förmed. The masses of native iron found in South America, in Siberia, and near Agnam, contaiu pickel, as bas been ascertained by Proust, Floward, and Klaproth, and resemble exactly the iron found in the stones fallen from the atmosphere. We have every reason therefore to ascribe to thein the same original : aud this accordingly is almost the uniform opi. nion of philosophers. Klaproth hath shown that real native iron is distinguished froin meteoric iron by the absence of nickel *.

[Good's Lucretius, Thomson's Chemistry. 2. Lunar or Selenitic Origin of Meteoric Stones. The best and fullest examination which has yet occurred to us upon this curious subject, is contained in a long and interesting original note of the Editors of the “ Philosophical Transactious Abridged,” appended to Dr. Halley's paper on Meteors, or lights

• Gehlen's Jour. i. 8.

This closing remark is a strong proof of the difference between the two, and the article which immediately follows is sufficient to show that the ingenious chemist is in an error, in conceiving that the hypothesis to which he soems to incline is “almost the uniform opinion of philosophers.”.

[EDITOR.

in the sky, published in vol. xxix. of the Transactions at large. The note is as follows:

Dr. Halley's mind fixes on nothing but vapour or exhalations, to solve the appearance; though the difficulty, not to say impossi. bility, of conceiving how any exhalations could be raised so high, ought to have hinted the idea of some other origin. Later obser. vations however have induced a belief, that these luminous appear. ances are allied to, if not the same as, the stones which have fre. quently been known to fall from the atmosphere, at different times, and in all parts of the earth. Several of the phænomena are common to both. These luminous bodies are seen to move with very great velocities, in oblique directions descending; com. monly with a loud bissing noise, resembling that of a mortar shell, or cannon ball, or rather that of an irregular hard mass projected violently through the air ; surrounded by a blaze or flame, taper. ing off to a narrow stream in the hinder part of it; are heard to explode or burst, and seen to fly in pieces, the larger parts going foremost, and the smaller following in succession ; are thus seen to fall on the earth, and strike it with great violence; that on exa. mining the place of the fall, the parts are found scattered about, being still considerably warm, and most of them entered the earth several inches deep. After so many facts and concurring circumstances, it is difficult to refuse assent to the identity of the two phænomena : indeed it seems now not to be doubted, but generally acquiesced in. And hence it is concluded, that every such meteor. like appearance is attended by the fall of a stone, or of stones, though we do not always see the place of the fall, nor discover the stones.

This conclusion, however, has contributed nothing towards dis. covering the origin of the phenomenon, at least as to its genera. tion in the atmosphere : on the contrary, it seems still more diffi. cult to accouut for the production of stones, than gaseous meteors, in the atmosphere, as well as to inflame and give them such violent motion. In fact, it seems concluded as a thing impossible to be done, or conceived; and philosophers have given up the idea as hopeless. This circumstance has induced them to endeavour to discover some other cause or origin for these phænomena. But no idea that is probable, or even possible, has yet been started; excepting one, by the very celebrated mathematician La Place, and

that of so extraordinary a nature, as to astonish us with its novelty and boldness of conception. This is no less than the conjecture, that these stony masses are projected from the moon! a conjecture which none but an astronomer could have made, or at least have shown to be probable, or even possible. Any ordinary person might at random utter the vague expression of a thing coming from the moon : but no one, except the philosopher, could propose the conjecture seriously, and prove its possibility. This M. La Place has been enabled to do by strict mathematical calculation. He has proved that a mass, if projected by a volcano from the moon, with a certain velocity, of about a mile and half per second, (which is possible to be done) it will thence be thrown beyond the sphere of the moon's attraction, and into the confines of the earth's; the consequence of which is, that the mass must presently fall to the earth, and become a part of it.

To prepare the way for a calculation, and a comparison of this supposed cause with the phænomena, it will be useful here to pre. mise a short account of the late and best observed circumstances in the appearance of fireballs, and the fall of stony masses from the atmosphere, extracted from the last published accounts of some of the more remarkable cases.

It is remarkable how generally the tradition has prevailed, in almost all ages, and among all people, of the fall of solid materials from the atmosphere, under the various denominations of thunder. bolts, showers of stones, masses of native iron, &c. generally believed by the common people ; who had often witnessed the fact, as coming from the sky or the heavens, and thence ascribed to the miraculous judgments of the Deity ; while they were as generally disbelieved by the philosophers, either because they had never seen them fall, or because they found it impossible to account for the cause of them.

In the later ages of the world, however, the fact has been observ. ed by more respectable evidences, and recorded with circumstances of considerable accuracy.

One instance of this kind, is that given by the celebrated astronomer Gassendi, who was an eye. witness of what he relates. November 27, 1627, the sky being quite clear, he saw a burning stone fall on mount Vaisir, in the south east extremity of France, near the city of Nice, on the coast of the Mediterranean Sea. While in the air, it seemed to be

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