Analysis of the Meteoric Iron, 415 



specific gravities of iron and nickel meteorolites as ranging 

 from 6 5 to 8-00. After the mass had been divided, the 

 specific gravity was taken in a similar manner to the above, 

 and the larger, heavier, and more solid half, gave a specific 

 gravity of 6*499 ; the smaller and lighter half, as already 

 mentioned by Dr Smith, having been broken in two, the pro- 

 cess of taking the specific gravity was repeated on each of 

 these, with the following results :-— 



The smaller, rounded, or lobed portion gave, 6-1919 

 The larger, or pointed portion of the mass, 6*7400 



The higher specific gravity of the pointed portion is appa- 

 rently accounted for by its having been compressed more than 

 the other parts. Dr Smith has also noticed that this portion 

 was stated to be tougher before the edge of the graver. 



The analysis was made on some filings of the mass obtained 

 before polishing the surfaces of the halves. I should have 

 preferred for this purpose a sample derived from various parts 

 of the mass, but this, it would appear, was not easy to obtain 

 without endangering the good appearance of the meteorolite. 



There is no point in the analysis calling for special descrip- 

 tion, except, perhaps, the determination of the nickel. This 

 metal was estimated by dissolving a known weight of the 

 meteorolite in hydrochloric acid, and after separation of the 

 gangue of carbon and silica, the iron was peroxodized by heat- 

 ing with nitric acid, and then the iron oxide was precipitated 

 by carbonate of baryta, and the excess of baryta afterwards re- 

 moved by sulphuric acid. The precipitate of sulphate of 

 baryta was separated by filtration, and the filtrate presented a 

 decided green colour, which on concentration was deepened, 

 showing the amount of nickel it contained to be considerable. 

 The nickel in this solution was then precipitated and weighed 

 as oxide. To arrive at a good result, it was necessary to 

 operate on as much as 60 or 70 grains of the meteorolite. In 

 the course of this process other metals, such as manganese, 

 chromium, cobalt, as well as magnetic oxide of iron, &c, were 

 carefully sought for, but no trace of them could be discovered. 

 The qualitative analysis, therefore, showed the presence of 



VOL. II, 3 H 



