Cn. XIL] METEORITES IN DRIFT. 177 



Erman, in his Archives of Eussia for 1841 (p. 314), cites a very cir- 

 cumstantial account drawn up by a Eussian miner of the finding of a 

 mass of meteoric iron in the auriferous alluvium of the Altai. Some 

 small fragments of native iron were first met with in the gold-washings 

 of Petropawlowsker in the Mrassker Circle ; but though they attracted 

 attention, it was supposed that they must have been broken off from the 

 tools of the workmen. At length, at the depth of 31 feet 5 inches from 

 the surface, they dug out a piece of iron we'ghing 17J pounds, of a 

 steel-gray color, somewhat harder than ordinary iron, and, on analyzing 

 it, found it to consist of native iron, with a small proportion of nickel, as 

 usual in meteoric stones. It was buried in the bottom of the deposit 

 where the gravel rested on a flaggy limestone. Much brown iron ore, 

 as well as gold, occurs in the same gravel, which appears to be part i i 

 that extensive auriferous formation in which the bones of the mammoth, 

 the Rhinoceros tichorhinus, and other extinct quadrupeds abound. No 

 sufficient data are supplied to enable us to determine whether it be of 

 Post-Pliocene or Newer Pliocene date. 



We ought not, I think, to feel surprise that we have not hitherto 

 succeeded in detecting the signs of such aerolites in older rocks, for, 

 besides their rarity in our own days, those which fell into the sea (and it 

 is with marine strata that geologists have usually to deal), being chiefly 

 composed of native iron, would rapidly enter into new chemical combi- 

 nations, the water and mud being charged with chloride of sodium and 

 other salts. We find that anchors, cannon, and other cast-iron imple- 

 ments which have been buried for a few hundred years off our English 

 coast have decomposed in part or entirely, turning the sand and gravel 

 which inclosed them into a conglomerate, cemented together by oxide of 

 iron. In like manner meteoric iron, although its rusting would be some- 

 what checked by the alloy of nickel, could scarcely ever fail to decompose 

 in the course of thousands of years, becoming oxide, sulphuret, or car- 

 bonate of iron, and its origin being then no longer distinguishable. The 

 greater the antiquity of rocks, — the oftener they have been heated and 

 cooled, permeated by gases or by the waters of the sea, the atmosphere 

 or mineral springs, — the smaller must be the chance of meeting with a 

 mass of native iron unaltered ; but the preservation of the ancient 

 meteorite of the Altai, and the presence of nickel in these curious bodies, 

 renders the recognition of them in deposits of remote periods less hope- 

 less than we might have anticipated. 



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