316 MR. E. W. BINNEY ON SOME SUPPOSED 



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 combinations, the water and mud being 

 charged with chloride of sodium and other acids. We 

 find that anchors, cannon, and other cast-iron implements, 

 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 enclosed them into a conglo- 

 merate, cemented together by oxide of iron. In like man- 

 ner meteoric iron, although its rusting would be somewhat 

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

 decompose in the course of thousands of years, becoming 

 oxide, sulphuret, or carbonate of iron, and its origin being then 

 no longer distinguishable. The greater the antiquity of 

 the rocks — the oftener they have been heated and cooled, 

 permeated by gases or by the waters of the sea, the atmo- 

 sphere or mineral springs — the smaller must be the chance 

 of meeting with a mass of native iron unaltered ; but the 

 presei-vation 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." 



In the translation of Humboldt's Cosmos, before cited, 

 at page 11 8 of Vol. I. is the foUojving passage, which, as it 

 contains valuable information on the subject before us, will 

 be given at length : — " The solid masses which reach the 

 earth— whether they have been seen to fall at night from 

 balls of fire, or in the daytime from a small dark cloud, 

 usually in a clear sky, and with a loud noise — though con- 

 siderably heated, are not incandescent. They exhibit, on 

 the whole, a general unmistakeable resemblance to one 

 another in their external form, in the nature of their crust, 

 and in the chemical composition of their principal constitu- 



