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3508

fubstances; and in this part of his task he was indebted to the learning and expertness of the Count de Bournon. The subftances were found to resemble each other very closely in their general' appearances, and in the nature of their component parts. The chief difference confisted in the different proportions in which the same component parts were combined, so as to form the aggregate of the heterogeneous maffes. Their specific gravities were nearly the same, unless that the abundance of iron in one of the masses caused a confiderable increase of its gravity. It may contribute to the formation of a precise estimate, if we present, in one view, the results of the experiments made to measure the specific gravities of the most remarkable specimens hitherto examined. The four last in the list were calculated by the Count de Bournon. The specific gravity of water being 1000, that of the Enfsheim stone is

3233 a Gaflendi'3* Bachelay'st

3535 Yorkshire Sienna

3418 Benares

3352 Bohemia

4281 All the stones examined by Count de Bournon and Mr Howard were found to consist of four distinct subftances; small metallic particles; a peculiar martial pyrites; a number of globular and elliptical bodies, also of a peculiar nature; and an earthy cement surrounding the other constituent parts. It was only the stone from Benares that Mr Howard could separate into its constituent parts, with sufficient accuracy, and in sufficient abundance, for a minute analysis of each. He found, however, that the nature of the metallic particles was the same in all; they were in each case an alloy of iron and nickel. In the pyrites of the Benares ftone, nickel as well as iron was detected; and the easy decompogtion of the pyrites by muriatic acid, in all the specimens, afforded a diftinguishing character of this substance. The globules in the Benares Itone contained Glica, magneha, and oxides. of nickel and iron ; the earthy cement confifted of the same fubstances, very nearly in the fame proportions. In the other Itones, these globules could not be easily separated from the cement and pyrites. Mr Howard, therefore, after freeing the aggregate as well as possible from the metallic particles, and several of the globules, was obliged to satisfy himself with analyzing the heterogeneous mass. Still the composition appeared wonderfully to agree with that of the basis and globules of

the

* Found in Provence,

+ Found in the Maine.

the Benares stone; as the following Table, collected from Mr Howard's experiments, and reduced to the parts of a hundred, will clearly evince.

Oxid of Oxid of Mag-silice
Nickel Iron. nefta.

2.5

15.

34.

32.

SGlobules
Stone from Benaresse

34.
- Yorkbire, Bafis, i.e. carthy cement, 2
with some globules and the pyrites deprived

· 24.6 50. of its sulphur

. Sienna. Balis

34.6 22.6 46.6 - - Bobenia. Bilgis

2.7 | 42.7 17.2 45.4 About the time that Mr Howard was engaged in these interest. ing researches, and before he had published the result of them, M. Vauquelin happened also to be occupied with the very same fub. ject. He analyzed, though by a different process, the Benares stone, and two others which fell in 1789 and 1790 in the south of France. The results of his experiments agreed with those of our distinguished countryman in every particular; and we are now entitled to conclude, with perfect confidence, that the stones which have at different times fallen upon the earth, in England, France, Italy, and the East Indies, are precisely of the same nature, confisting of the same simple substances arranged in similar compounds, nearly in the same proportions, and combined in the same inanner, so as to form heterogeneous aggregates whose general resemblance to each other is complete. We are further warranted in another important inference, that no other bodies have as yet been discovered on our globe, which contain the same ingredients; and, more particularly, that the analysis of these stones has made us acquainted with a species of pyrites not formerly known, nor any where else to be found.

The general analogy between these stones and the masses of native iron found in different parts of the world, was too striking to escape the eminent inquirers who have investigated this subject. They resemble each other in their external character, though not by any means so closely as the stones ; but in one circumstance of their chemical compofition, they have a remarkable similarity, both among themselves, and towards the stony substances. M. Proust, a conliderable time before the date of Mr Howard's discoveries, had proved that the enormous mass of native iron found in South

America, contained a large portion of nickel in its composition. Mr Howard was led to the fame conclusion by analyzing another portion of this body; and he found that the solitary masses discovered in Siberia, Bohemia, and Senegal, contained a mixture of the same metal with iron, though in various proportions. The Bo

hemian iron is an alloy, of which nickel forms eighteen parts in the hundred; in the Siberian iron, it forms seventeen ; and in the Senegal iron, five or fix. But what is still more striking, and tends to place the similarity of their origin beyond all doubt, the Siberian mass is interspersed with cavities, containing an earthy substance of the very fame nature as the earthy cement and glo. bules of the Benares stone ; nay, the proportions of the ingredients, according to Mr Howard's analysis, are nearly alike, if we except that of the oxide of iron, which is considerably smaller in the Siberian earth. This curious fact excites the strongest prepoffession in favour of the idea, that the Siberian iron owes its origin to the same causes which formed and projected the dif. ferent stones supposed to have fallen on the earth; and, coupled with the other details of the analysis, it naturally leads us to conclude, that the masses of native iron, as they are called, differ in no respect from the metallic particles, or the alloy of iron and nickel, which constitute one of the four aggregate parts in every stone hitherto examined.

It may be remarked, that, excepting the tradition of the Tartars refpecting the fall of the Siberian iron from heaven, no external evidence has been preserved to illustrate the origin of those masses of native metal which have been analyzed by chemists. A tolerably authentic testimony has, however, been lately found, to prove the fall of a similar body in the East Indies. Mr Greville has communicated to the Royal Society (Phil. Tranf. 1803, pt. I.), a very interesting document, translated from the Emperor Tchangire's Memoirs of his own reign. The Prince relates, that in the year 1620 (of our æra), a violent explosion was heard at a village in the Punjaub, and during the noise, a luminous body fell from above on the earth. That the amnil (or fiscal officer) of the district immediately repaired to the spot where the body was said to have fallen, and having found it to be still hot and not burnt up, caused it to be dug; when the heat increasing, he at last came to a lump of iron violently hot; that this was sent to court, where the Emperor had it weighed in his presence, and ordered it to be forged into a sabre, a knife, and a dagger ; that the workmen reported it was not malleable, but shivered under the stroke ; and that it required to be mixed up with one third part of common iron, when the mass was found to make excellent blades. The Royal hisorian adds, that upon the incident of this iron of lightning being manufactured, a poet presented him with a distich, purporting that, ' during his reign, the earth attained order and regularity; that raw iron fell from lightning, and was, by his world-lubduing authority, converted into a dagger, a knife, and two fabres.' VOL. III. NO. 6. Dd

The

The exact resemblance of the occurrence here related, in all its efTential circumstances, to the accounts of fallen stones formerly detailed, and the particular observation upon the unmalleable nature of the iron, give, it must be confessed, a very great de. gree of credibility to the whole narrative, and bestow additional weight on the inference previously drawn from internal evidence, that the folitary masses of natire iron found in different quarters of the globe, have the same origin with the stones analyzed by Vauquelin and Howard.

We have now gone through the whde evidence, both with respect to the circumstances in which these singular bodies are found, the ingredients of which they are compounded, and the outward appearance and structure which they exhibit : we are now to consider the inferences respecting their probable origin, which this mass of information may warrant us to draw.

Independent of the distinct negative which the external evidence gives to any such conclusions, we are fully entitled to deny that these bodies are formed in the ground by lightning, or existed previoully there, both from their exact resemblance to each other in whatever part of the earth they have been found, and from their containing substances nowhere else to be met with. It cannot surely be imagined, that exactly in those spots where fire, of some · unknown kind, precipitated from an exploded meteor, happened

to fall, there should exist certain proportions of iron, sulphur, · nickel, magnesra and filica, ready to be united by the heat or

electricity. Still less conceivable is it, that in every such fall of fire, those ingredients should first combine, by twos and threes, in the very fame manner, and then that the binary and ternary compounds should unite in similar aggregates. But, least of all is it reasonable to fuppose, that bodies formed in the earth fhould, upon being dug up, be found enveloped in a crust different from the rest of their substance, and bearing evident marks of having undergone the action of heat in contact with the air.

The same unquestionable resemblance which prevails among all these bodies, and, ftill more, the peculiar nature of the pyrites which they contain, prove very clearly that they have not a volcanic origin. Even if such an hypothesis were liable to no other objection, it would be inadmissible on this ground, that we know of no volcano which throws up so small a portion of matter, and so uniformly of the same kind. But though we were to admit the existence of this volcano, where must we place it, that its eruptions may extend from Bengal to England, France, Italy, and Bohemia; nay, from Siberia to Senegal and South America ? And if we are forced to admit the existence of a series of such volcanoes, which are known to us only by these peculiar effects of their eruptions, do

We

we not acknowledge that we are compelled to imagine a set of causes, without any other foundation for our belief in them, than our occasion for their assistance in explaining the pheno. menon ? In short, do we not account for one difficulty, by fancying a greater ! But if it is alleged that the stones come from volcanoes already known, we demand, what volcano exists in the Peninsula of India, or in England, or in France, or in Bohemia ? And if it is said that these bodies are projected by Hecla, Ætna, &c. to all manner of distances, we must alk, whether this is not

*plaining what is puzzling, by assuming what is impoffible? It 15 Jurely, much better to rest satisfied with recording the fact, and leaving it under all its difficulties, than to increase its wonders by the addition of a miracle.

The lame remark may be extended to those who have fancied mat the constituent parts of the stones exist in the atmofphere, o are united by the fire of a meteor, or by the electric fluid.

have no right to make any such hypothesis. We have never scen iron, filica, &c. in the gazeous state. These bodies may, for

we know, be compounds of oxygen and azote or hydroAc. ; but as yet we have no reason to think so. Besides, ano amuses us with this clumsy and gratuitous explication,

obably account for every other phenomenon by a similar Sof creation: He may, with equal plausibility, conceive th to be formed by a union of burnt gases, and then coith vegetables, and people it with living creatures, by a

re conflagrations and explosions. Such, however, is the and unpr

most heavily expounded by M. Izarn—spun, with tiresome Profitable industry, into cobwebs, which touch every fact,

Catching it—and enveloped in the mist of general logical

as, which faintly conceal the fundamental postulate-an entire act of creation. tion have

m the whole, we may safely infer, that the bodies in quef

ve fallen on the surface of the earth, but that they were not prois

ojected by any volcanoes, and that we have no right, from Town laws af nature, to suppose that they were formed in

Pper regions of the atmosphere. Such a negative concluentitled i

ems all that we are, in the present state of our knowledge, a to draw. But an hypothelis may perhaps suggeit itself, mbered by any of the foregoing difficulties, it we attend

following undoubted truths. tary synte

the attraction of gravitation extends over the whole planeItem, a heavy body, placed at the surface of the Moon, cted chiefly by two forces; one drawing it towards the of the Earth, and ano:her drawing it towards that of the The latter of these forces, however, is beyond all com

the earth to be formed ver it with vegetables, and few more conflagrat theory most heavily.

the known laws the upper regi

unincumbered by any

As the attraction

Dd 2

is affected chiefly, by centre of the Lar Moon. The !

parison

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