Изображения страниц
PDF
EPUB

which the luminous body or its to whose inspection many of the fragments were seen to move : fallen bodies were submitted. But the scattering or ploughing up of fortunately a considerable number the soil at those spots, always in of these singular substances have proportion to the size of the stones; been examined, with the greatest the concussion of the neighbour- care, by the first chemists and naing ground at the time; and, above turalists of the age ; and their inall, the impinging of the stones vestigations have put us in posupon bodies somewhat removed session of a mass of information, from the earth, or lying loose capable of convincing the most upon its surface are circum- scrupulous inquirer, that the bodies stances perfectly well authenticat. in question have a common origin, ed in these reports ; and, when and that we are as yet wholly untaken together, are obviously fatal acquainted with any natural proto any theory, either of the mas. cess which could have formed ses having previously existed in them on our globe. the soil ready formed, and hay. M. De la Lande appears to have ing been disclosed by the electrick examined the stones which fell fuidor of their component parts near Bourg, in the province of having existed there, and having Bresse, 1753, with some attention. been united and consolidated by He remarks their external coating that fluid.

of black vitrified matter, the metal. II. While the internal evidente lick or pyritical threads intersper on this question, that is, the infer- sed through them, and more parence arising from an examination ticularly the cracks filled with me. of the stones themselves, agrees tallick particles. His chemical most harmoniously with the con- analysis is very meagre and unclusion to which the narratives satisfactory ; but such as it was, above analyzed force our assent, its results, as well as the general and greatly strengthens that con- observations of external character, clusion, it also leads to a farther corresponded with the inferences knowledge of the subject, than the drawn by him from a similar examere external evidence could of mination of the stone which fell, itself have afforded us.

in 1750, near Coutances, in NorThe reports from all those who mandy, at the distance of three observed the meteors, and found hundred and sixty miles from the stones in the neighbourhood, Bourg. after the explosions, agree in des. The external appearance of the cribing those substances as differ. three stones presented to the Acad. ent from all the surrounding bodies, emy of Sciences, as having fallen and as presenting, in every case, in different parts of France during the same external appearance of the year 1768, was precisely the semi-metallick matter, coated on same. But Messrs. Lavoisier, &c. the outside with a thin black crust, the committee appointed to exam. and bearing strong marks of re- ine them, performed the chemical cent fusion. This general re- analysis with much greater accu. semblance we should be perfectly racy and fulness than M. De la entitled to infer from the various Lande had done. That which fell accounts of eye-witnesses, even if in the Maine, and was presented no more particular observations by the Abbe Bachely, underwent had been made by men of science, the most careful process. It was

found to contain, of sulphur, 81 sis pursued both by Barthold and per cent. ; iron, 36 ; vitrifiable the academicians, the metallick earth, 55. It must be remarked, particles were not examined with however, that this decomposition sufficient precision. The specifick was effected by means of experi- gravity of the stones examined by ments performed upon an integral the academicians was to that of part of the whole stone, consider water, as 3535 to 1900. The spe- : ed as a homogeneous substance ; cifick gravity of the stone of En. whereas, it is in fact a congeries sisheim, as tried by Barthold, was of substances, which ought to have 3233; that of the stone examined been separately analyzed. This by Gassendi (who saw it fall) was consideration will, in part at least, 14, common marble being 11; enable us to account for the ap- and, taking the specifick gravity of parent discrepancy between the marble to that of water, as 2716 to results obtained by the academi. 1000, the specifick gravity of the cians and those of later experi- stone observed by Gassendi will mentalists. Messrs. Lavoisier, &c. be to that of water as 3456 to 1000. also examined particularly another So near a coincidence between obstone, said to have fallen in a dif- servations, made at such a distance ferent part of France, and obtained of time, upon these various subvery nearly the same results. The stances, cannot fail to strike us as only difference was, that it did not very remarkable, and to prepare give out sulphurated hydrogenous us for that fuller demonstration of gas when acted upon by the mu. their identity, which was reserved riatick acid ; a peculiarity distinct. for the labours of our countryman ly observable in the other sub. Mr. Howard. stance.

This excellent philosopher has The description which Professor elucidated the subject of our preBarthold gives of the external sent consideration, by a course of character of the stone which fell experiments, as interesting and innear Ensisheim, in the fifteenth structive as any that the science of century, corresponds exactly with chemical analysis can boast of. the descriptions given of these He fortunately obtained specimens stones, and of the ores examined of the stones, which fell in several by M. De la Lande. The results very distant quarters of the globe; of his analysis are somewhat dif, the Benares, and in Yorkshire (as ferent ; but he examined the whole we have already describedl); near heterogeneous compound, and not Sienna, and in Bohemia, according the parts separately. He conclud. to evidence not altogether so satis, ed, that this mass contained 2 per factory, as that upon which the cent. of sulphur, 20 of iron, 14 other narratives rest. magnesia, 17 alumina, 2 lime, 42 He began his inquiries, very jusilica.' Mr. Howard has very just. diciously, by a minute examination ly remarked, that the Professor's of the external mineralogical charown account of his experiments is acters of these four substances ; at variance with the idea of lime and in this part of his task he was being contained in the substance ; indebted to the learning and exand that he has given no sufficient pertness of the Count de Bournon. proof of the existence of alumina. The substances were found to reIt is also to be observed, that from semble each other very closely in the exceptionable method of analy, their general appearances, and in

the nature of their component Benares that Mr. Howard could parts. The chief difference con- separate into its constituent parts, sisted in the different proportions with sufficient accuracy, and in sufin which the same component ficient abundance, for a minute parts were combined, so as to form analysis of each. He found, howthe aggregate of the heterogene- ever, that the nature of the metalous masses. Their specifick gra- lick particles was the same in all ; vities were nearly the same, unless they were in each case an alloy of that the abundance of iron in one iron and nickel. In the py rites of of the masses caused a considera- the Benares stone, nickel as well ble increase of its gravity. It may as iron was detected ; and the easy contribute to the formation of a decomposition of the pyrites by precise estimate, if we present, in muriatick acid, in all the specione view, the resalts of the experie mens, afforded a distinguishing ments made to measure the spe- character of this substance. The cifick gravities of the most re- globules in the Benares stone conmarkable specimens hitherto ex- tained silica, magnesia, and oxides amined. The four last in the list of nickel and iron ; the earthy cewere calculated by the Count de ment consisted of the same subBournon. The specifick gravity stances, very nearly in the same of water being 1000, that of the proportions. In the other stones Ensisheim stone is

3233 these globules could not be easily Gassendi's*

3456 separated from the cement and Bachelay'st

3535 pyrites. Mr. Howard, therefore, Yorkshire

3508 after freeing the aggregate as well Sienna

3418 as possible from the metallick parBenares

3352 ticles, and several of the globules, Bohemia

4281 was obliged to satisfy himself with All the stones examined by analyzing the heterogeneous mass. Count de Bournon and Mr. How. Still the composition appeared ard were found to consist of four wonderfully to agree with that of distinct substances ; small metal- the basis and globules of the Belick particles ; a peculiar martial nares stone ; as the following Ta. pyrites ; a number of globular and ble, collected from Mr. Howard's elliptical bodies, also of a peculiar experiments, and reduced to the Dature ; and an earthy cement parts of a hundred, will clearly surrounding the other constituent evince. parts. It was only the stone from

Oxide of | Oxide of | Magne- | Silica.
Nickel. Iron.

[merged small][merged small][merged small][merged small][merged small][merged small][merged small][ocr errors][ocr errors][ocr errors][merged small][ocr errors][merged small]

About the time that Mr. How- Howard's discoveries, had proved ard was engaged in these interesting that the enormous mass of native researches, and before he had pub- iron found in South America, conlished the result of them, M. Vau- tained a large portion of nickel in quelin happened also to be occupi- its composition. Mr. Howard was ed with the very same subject. He led to the same conclusion by ana. analyzed, though by a different lyzing another portion of this boprocess, the Benares stone, and dy ; and he found that the solitary two others which fell in 1789 and masses discovered in Siberia, Bo1790 in the south of France. The hemia, and Senegal, contained a results of his experiments agreed mixture of the same metal with with those of our distinguished iron,though in various proportions. countryman in every particular ; The Bohemian iron is an alloy, of and we are now entitled to con- which nickel forms eighteen parts clude, with perfect confidence, that in the hundred ; in the Siberian the stones, that have at different iron, it forms seventeen ; and in times fallen upon the earth, in Eng. the Senegal iron, five or six. But land, France, Italy, and the East- what is still more striking, and Indies, are precisely of the same tends to place the similarity of nature, consisting of the same sim- their origin beyond all doubt, the ple substances, arranged in similar Siberian mass is interspersed with compounds, nearly in the same cavities, containing an earthy subproportions, and combined in the stance of the very same nature, as same manner, so as to form heter- the earthy cement and globules of ogeneous aggregate whose general the Benares stone ; nay, the proresemblance to each other is com- portions of the ingredients, accord. plete. We are further warranted ing to Mr. Howard's analysis, are in another important inference, nearly alike, if we except that of that no other bodies have as yet the oxide of iron, which is consid. • been discovered on our globe, erably smaller in the Siberian which contain the same ingredi- earth. This curious fact excites ents ; and, more particularly, that the strongest prepossession in fathe analysis of these stones has vour of the idea, that the Siberian made us acquainted with a species iron owes its origin to the same of pyrites not formerly known, nor causes, which formed and projectany where else to be found.

ed the different stones supposed to The general analogy between have fallen on the earth : and, these stones and the masses of na- coupled with the other details of tive iron found in different parts of the analysis, it naturally leads us the world, was too striking to es- to conclude, that the masses of nacape the eminent inquirers who tive iron, as they are called, differ have investigated this subject. in no respect from the metallick They resemble each other in their particles, or the alloy of iron and external character, though not by nickel, which constitute one of the any means so closely as the stones: four aggregate parts in every stone but in one circumstance of their hitherto examined. chemical composition they have a 2 It may be remarked, that, ex remarkable similarity, both among cepting the tradition of the Tartars themselves, and towards the stony respecting the fall of the Siberian substances. M. Proust, a consid- iron from heaven, no external evi. erable time before the date of Mr. dence has been preserved to illus

[graphic]

trate the origin of those masses of of the iron, give, it must be connative metal which have been ana- fessed, a very great degree of credlyzed by chemists. A tolerably ibility to the whole narrative, and authentick testimony has, however, bestow additional weight on the been lately found to prove the fall inference previously drawn from of a similar body in the East-In- internal evidence, that the solitary dies. Mr. Greville has communi. masses of native iron, found in difcated to the Royal Society (Phil. ferent quarters of the globe, have Trans. 1803, pt. I.), a very inter- the same origin with the stones esting document, translated from analyzed by Vauquelin and Howthe Emperour Jehangire's Memoirs ard. of his own reign. The prince re We have now gone through the lates, that in the year 1620 (of our whole evidence, both with respect zra), a violent explosion was heard to the circumstances in which at a village in the Punjaub, and, these singular bodies are found, during the noise, a luminous body the ingredients of which they are fell from above on the earth. That compounded, and the outward apthe aumil (or fiscal officer) of the pearance and structure which they district immediately repaired to exbibit : we are now to consider the spot where the body was said the inferences respecting their to have fallen, and finding the probable origin, which this mass ground still hot and burnt up, of information may warrant us to caused it to be dug ; when the heat draw. increasing, he at last came to a Independent of the distinct neglump of iron violently hot ; that ative which the external evidence this was sent to the court, where gives to any such conclusions, we the Emperour had it weighedin his are fully entitled to deny that these presence, and ordered it to be forg- bodies are formed in the ground ed into a sabre, a knife, and a dag- by lightning, or existed previously ger ; that the workman reported there, both from their exact reit was not malleable, but shivered semblance to each other in whatevunder the stroke ; and that it re- er part of the earth they have been quired to be mixed up with one third found, and from their containing part of common iron, when the mass substances no where else to be Was found to make excellent blades. met with. It cannot surely be

The Royal historian adds, that up- imagined, that exactly in those on the incident of this iron of spots where fire, of some unknown lightning being manufactured, a kind, precipitated from an explodpoet presented him with a distich, ed meteor, happened to fall, there purporting that, during his reign, should exist certain proportions of the earth attained order and regu- iron, sulphur, nickel, magnesia larity ; that raw iron fell from and silica, ready to be united by lightning, and was, by his world- the heat or electricity. Still, less

subduing authority, converted into conceivable is it, that, in every such "a dagger, a knife, and two sabres. fall of fire, those ingredients should

The exact resemblance of the first combine, by twos and threes, occurrence here related, in all its in the very same manner, and then essential circumstances, to the ac- that the binary and ternary comcounts of fallen stones formerly de pounds should unite in similar agtailed, and the particular observa- gregates. But, least of all is it reation upon the unmalleable nature sonable to suppose, that bodies

[graphic]
[graphic]
[graphic]
« ПредыдущаяПродолжить »