The Siberian mass of native iron was first transport ed to Krasnojark, where it was found to weigh fifteen quintals. In 1772, it was conveyed to St. Petersburgh, and deposited in the collections of the Imperial Aca demy of Sciences. M. P win, who examined it in 1778, describes it as a large bomb, somewhat flattened, and partly covered with a rough ochraceous crust. So bard and compact was it in its natural state, that three or four forgers employed between ten and twelve hours in detaching from it a fragment of two pounds weight.
Of a similar description seems to have been the frag ment which was found between Eibenstock and Jo hanngeorgenstadt.—Another, probably from Norway, preserved in the Imperial Cabinet of Vienna.—A small mass, of some pounds weight, kept at Gotha.—A mass, found under the pavement of Aken, near Magdeburg. Loeber.—A mass of iron from the coast of Honduras. Annals of Phil.—Scattered masses of black rock, con taining native iron, on the right bank of the Senegal. Compagnon, Forster, A mass of iron at the Cape of Good Elope, in which Stromeyer detected the presence of cobalt. Von ifarurn and Dankelman.
In the Philosophical Transactions for 1816, there is an interesting history and accoudt of a mass of native iron, found in the province of Bahia in Brazil, commu nicated by A. F. Mornay, Esq. to Dr. Wollaston. It is about seven feet long, four feet wide, and two feet in thickness, its solid contents being rudely estimated on the spot at twenty cubic feet, and its weight at 14,000 lb. The colour of the top and sides is chesnut, and the surface glossy, though not smooth, being slightly in dented all over, as if hammered, while the hollow pact underneath is covered with a flaky crust, whose exter nal surface is rusty. Here we should not overlook, that the cavities, or indentations on the surface, are sometimes also observed on well ascertained meteorites. Thus one of the Siena stones is described by Mr. King, " as having many rounded cavities on its surface ; as if the stone had been struck with small balls whilst it was forming, and before it was hardened, which left their impressions. And some appearances of the same kind," he adds, " were found on one of the four surfaces of another stone in the possession of Soldani." The sur face of the Yorkshire stone, too, presents similar cavi ties or depressions. Wherever the Brazilian block is struck with a steel, it gives out abundance of sparks, and, when rubbed with a quartz pebble in the dark, it becomes beautifully luminous. It is not only magne tic, but manifests well-defined poles. Small fragments were detached from it with much difficulty, and re vealed an internal crystallization, not previously noticed in meteoric iron. From the observations and experi ments of Dr. 'Wollaston on the specimens transmitted to him, it appears that the texture of this iron is nut only crystalline, but that it is disposed to break in the forms of the regular octohedron and tetrahedron, or in the rhomboid, a combination of both these lorms.
" Though the fragments," observes the Dr. e 6 arc not in the least attractive as magnets, and have in them selves no polarity, they are precisely like any other pieces of the best soft iron, and assume polarity instant ly, according to the position in which they are held with respect to the magnetic axis of the earth. When a long fragment is held in a vertical position, its lower extremity being then within 20° of the (lip of the north magnetic pule, becomes north, and repels the north pole of a magnetic needle suspended horizontally. But this power is instantly reversed, by being suddenly inverted : so that the apparent contradiction between the observed polarity of the mass, and the seeming want of it in the fragments, is thus completely re moved.
" Although Mr. Mornay reasonably expected, that this iron would not differ from the many others now on record that have been found in various parts of the world, and from his experiments was led to infer the presence of nickel, it appeared desirable to ascertain this point with more precision than he had been ena bled to do, acid to determine also in what proportion this peculiar ingredient of meteoric bodies might be found to prevail." Then, after detailing the steps of
his process, he thus concludes: "From the presence of nickel in this mass, we can not but regard it as having the same meteoric origin with the various other specimens that have been found; and although in the spot whence it had been first re moved Mr. Mornay discovered a bed of matter, from which it appears, by analysis, that similar iron might be formed by art, it seems by far more probable that an opposite change has really taken place, and that the whole of this supposed ore is the result of progressive oxidation during a series of years, of which we have no other evidence, and affords the sole ground on which a conjecture could be formed of the very remote period at which this problematic body has fallen upon the earth." Since the expulsion of the Spaniards from the pro vince of the great Chaco Gulamba, the country situa ted to the south of the river Vermejo, and to the west. of the Parana, has been mostly abandoned. A few In dians only inhabit the district of St. Jago del Estero, to gather the honey and bees-wax which abound in the woods. These Indians discovered, in the middle of a very extended plain, a considerable mass of metal, which they reported to be iron. When the viceroy of Peru was apprized of this discovery, he was struck with the singularity of the phenomenon, because there arc no hills in that part of the country, and scarcely a stone of any description is to be found within a circum ference of a hundred leagues. Some individuals, re gardless of every danger, and stimulated by the pros pect of gain, repaired to the spot to obtain some por tions of the metal, and actually conveyed specimens of it to Lima and Madrid ; but the only fruit of their toils, was the assurance that the substance with which they had loaded themselves was very fine and malleable iron. According ,to these adventurers, the vein ex tended several leagues, and promised an abundant pro duce. The viceroy of Rio de la Plata, therefore, dis patched Don Celis to examine the mass with greater accuracy, and to fix some settlers in the neighbourhood, if he should judge the working beneficial. Cells de parted, accordingly, from Rio Salado, on the 3d of Fe bruary, 1783, accompanied by the requisite attendants; and, after performing a journey of seventy leagues, through a fine level country, he reached the spot, which, agreeably to his observations, is in 27° 28' of south lati tude. He found the ferruginous mass mostly buried in pure clay. Its external surface was very compact ; but, on breaking some pieces from it, he perceived that its substance was full of cavities, as if the whole had at one time undergone fusion. In the course of separat ing 25 or 30 bits, the seventy chisels with which he had been furnished, were rendered useless. On re moving the surrounding earth, he observed that all the surface which had beet) covered by the soil was inves ted with a layer of rust, of about six inches thick, and which he ascribed to the humidity of the ground. Having rent it in two different places by the force of gunpowder, he examined the deepest chasm, and found it precisely of the same nature with that of the surface, and also with the earth which was dug at a hundred paces to the east and west of the mass. As he could not conceive the latter, under the circumstances in which he found it, to be produced by any Natural process, or conveyed by human means, he prestm.ed that it must have been projected by some volcanic explosion. Ac cording to its cubical measure, and allowing a specific gravity somewhat greater than that of iron, this enor mous mass should weigh about 300 quintals.