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which the luminous body or its fragments were seen to move the scattering or ploughing up of the soil at those spots, always in proportion to the size of the stones; the concussion of the neighbouring ground at the time; and, above all, the impinging of the stones upon bodies somewhat removed from the earth, or lying loose upon its surface-are circumstances perfectly well authenticat ed in these reports; and, when taken together, are obviously fatal to any theory, either of the masses having previously existed in the soil ready formed, and having been disclosed by the electrick fluid-or of their component parts having existed there, and having been united and consolidated by that fluid.

II. While the internal evidence on this question, that is, the inference arising from an examination of the stones themselves, agrees most harmoniously with the conclusion to which the narratives above analyzed force our assent, and greatly strengthens that conclusion, it also leads to a farther knowledge of the subject, than the mere external evidence could of itself have afforded us.

The reports from all those who observed the meteors, and found the stones in the neighbourhood, after the explosions, agree in describing those substances as differ ent from all the surrounding bodies, and as presenting, in every case, the same external appearance of semi-metallick matter, coated on the outside with a thin black crust, and bearing strong marks of recent fusion. This general resemblance we should be perfectly entitled to infer from the various accounts of eye-witnesses, even if no more particular observations had been made by men of science,

to whose inspection many of the fallen bodies were submitted. But fortunately a considerable number of these singular substances have been examined, with the greatest care, by the first chemists and naturalists of the age; and their investigations have put us in possession of a mass of information, capable of convincing the most scrupulous inquirer, that the bodies in question have a common origin, and that we are as yet wholly unacquainted with any natural process which could have formed them on our globe.

M. De la Lande appears to have examined the stones which fell near Bourg, in the province of Bresse, 1753, with some attention. He remarks their external coating of black vitrified matter, the metal. lick or pyritical threads intersper sed through them, and more particularly the cracks filled with me. tallick particles. His chemical. analysis is very meagre and un satisfactory; but such as it was, its results, as well as the general observations of external character, corresponded with the inferences drawn by him from a similar exa mination of the stone which fell,. in 1750, near Coutances, in Nor. mandy, at the distance of three hundred and sixty miles from Bourg.

The external appearance of the three stones presented to the Acad. emy of Sciences, as having fallen in different parts of France during the year 1768, was precisely the same. But Messrs. Lavoisier, &c. the committee appointed to examine them, performed the chemical analysis with much greater accu racy and fulness than M. De la Lande had done. That which fell in the Maine, and was presented by the Abbe Bachely, underwent the most careful process. It was

found to contain, of sulphur, 8 sis pursued both by Barthold and

per cent.; iron, 36; vitrifiable earth, 55. It must be remarked, however, that this decomposition was effected by means of experiments performed upon an integral part of the whole stone, considered as a homogeneous substance; whereas, it is in fact a congeries of substances, which ought to have been separately analyzed. This consideration will, in part at least, enable us to account for the apparent discrepancy between the results obtained by the academicians and those of later experimentalists. Messrs. Lavoisier, &c. also examined particularly another stone, said to have fallen in a different part of France, and obtained very nearly the same results. The only difference was, that it did not give out sulphurated hydrogenous gas when acted upon by the muriatick acid; a peculiarity distinctly observable in the other sub

stance.

The description which Professor Barthold gives of the external character of the stone which fell near Ensisheim, in the fifteenth century, corresponds exactly with the descriptions given of these stones, and of the ores examined by M. De la Lande. The results of his analysis are somewhat different; but he examined the whole heterogeneous compound, and not the parts separately. He conclud. ed, that this mass contained 2 per cent. of sulphur, 20 of iron, 14 magnesia, 17 alumina, 2 lime, 42 silica. Mr. Howard has very just ly remarked, that the Professor's own account of his experiments is at variance with the idea of lime being contained in the substance; and that he has given no sufficient proof of the existence of alumina. It is also to be observed, that from the exceptionable method of analy.

the academicians, the metallick particles were not examined with sufficient precision. The specifick gravity of the stones examined by the academicians was to that of water, as 3535 to 1000. The spe-cifick gravity of the stone of Ensisheim, as tried by Barthold, was 3233; that of the stone examined by Gassendi (who saw it fall) was 14, common marble being 11; and, taking the specifick gravity of marble to that of water, as 2716 to 1000, the specifick gravity of the stone observed by Gassendi will be to that of water as 3456 to 1000. So near a coincidence between observations, made at such a distance of time, upon these various substances, cannot fail to strike us as very remarkable, and to prepare us for that fuller demonstration of their identity, which was reserved for the labours of our countryman Mr. Howard.

This excellent philosopher has elucidated the subject of our present consideration, by a course of experiments, as interesting and instructive as any that the science of chemical analysis can boast of. He fortunately obtained specimens of the stones, which fell in several very distant quarters of the globe ; the Benares, and in Yorkshire (as we have already described); near Sienna, and in Bohemia, according to evidence not altogether so satisfactory, as that upon which the other narratives rest.

He began his inquiries, very judiciously, by a minute examination of the external mineralogical characters of these four substances; and in this part of his task he was indebted to the learning and expertness of the Count de Bournon. The substances were found to resemble each other very closely in their general appearances, and in

the nature of their component parts. The chief difference consisted in the different proportions in which the same component parts were combined, so as to form the aggregate of the heterogeneous masses. Their specifick gravities were nearly the same, unless that the abundance of iron in one of the masses caused a considerable 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 specifick gravities of the most remarkable specimens hitherto examined. The four last in the list were calculated by the Count de Bournon. The specifick gravity of water being 1000, that of the Ensisheim stone is 3233 Gassendi's*

Bachelay'st

Yorkshire

Sienna

Benares
Bohemia

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 metallick particles was the same in all; they were in each case an alloy of iron and nickel. In the py rites of the Benares stone, nickel as well as iron was detected; and the easy decomposition of the pyrites by muriatick acid, in all the specimens, afforded a distinguishing character of this substance. The globules in the Benares stone contained silica, magnesia, and oxides of nickel and iron; the earthy cement consisted of the same substances, very nearly in the same proportions. In the other stones these globules could not be easily separated from the cement and 3535 pyrites. Mr. Howard, therefore, 3508 after freeing the aggregate as well 3418 as possible from the metallick par3352 ticles, 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 Benares stone; as the following Table, collected from Mr. Howard's experiments, and reduced to the parts of a hundred, will clearly evince.

3456

4281

All the stones examined by Count de Bournon and Mr. How ard were found to consist of four distinct substances; small metallick 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

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About the time that Mr. Howard was engaged in these interesting researches, and before he had published the result of them, M. Vauquelin happened also to be occupied with the very same subject. 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, that have at different times fallen upon the earth, in England, France, Italy, and the EastIndies, are precisely of the same nature, consisting of the same simple substances, arranged in similar compounds, nearly in the same proportions, and combined in the same manner, so as to form heterogeneous aggregate 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 composition they have a remarkable similarity, both among themselves, and towards the stony substances. M. Proust, a considerable 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 same 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 Bohemian 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 six. 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 same nature, as the earthy cement and globules of the Benares stone; nay, the proportions of the ingredients, accord. ing 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 prepossession in favour of the idea, that the Siberian iron owes its origin to the same causes, which formed and projected the different 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 metallick 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, ex. cepting the tradition of the Tartars. respecting the fall of the Siberian iron from heaven, no external evidence has been preserved to illu

trate the origin of those masses of native metal which have been analyzed by chemists. A tolerably authentick 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. Trans. 1803, pt. I.), a very interesting document, translated from the Emperour Jehangire's Memoirs of his own reign. The prince relates, that in the year 1620 (of our zra), 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 aumil (or fiscal officer) of the district immediately repaired to the spot where the body was said to have fallen, and finding the ground still hot and 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 the court, where the Emperour had it weighed in his presence, and ordered it to be forged into a sabre, a knife, and a dagger; that the workman 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 historian 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 worldsubduing authority, converted into a dagger, a knife, and two sabres.'

The exact resemblance of the occurrence here related, in all its essential 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 degree of credibility to the whole narrative, and bestow additional weight on the inference previously drawn from internal evidence, that the solitary masses of native 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 whole 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 previously there, both from their exact resemblance to each other in whatever part of the earth they have been found, and from their containing substances no where 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, magnesia and silica, 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 same manner, and then that the binary and ternary compounds should unite in similar aggregates. But, least of all is it reasonable to suppose, that bodies

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