22 Professor Apjohn on a Meteoric Stone 



Sulphuret of iron 8.75 



Iron 43.87 



Nickel 2.28 



Protoxide of iron 10.71 



Magnesia . 18.69 



Lime ' . . 0.52 



84.82 



This part of the analysis having been completed, it appeared to me that it 

 would be interesting, before proceeding further, to examine the oxide of nickel 

 above obtained, for the purpose of ascertaining whether it included any cobalt, 

 these two metals being so frequently found associated in nature. 



With this view 2.67 grs. of the oxide were dissolved in muriatic acid, and to 

 the solution ammonia was added in excess, which threw down a very minute quan- 

 tity of peroxide of iron. This latter being separated by filtration, caustic potash 

 was added in considerable excess to the ammoniacal solution, and the oxide of 

 nickel thus precipitated was separated by filtration. Through the filtered fluid 

 sulphureted hydrogen was now passed. This, upon the application of heat, de- 

 termined a small amount of dark precipitate, which, upon examination, proved to 

 be sulphuret of cobalt. Thus it dissolved in nitric acid with the separation of 

 sulphur ; and the solution, when heated by the blowpipe with alumina, gave to 

 this earth a beautiful blue colour. The quantity of the cobalt present was not 

 determined, but its amount was undoubtedly extremely small. 



We now return to the portion (B) of the aerolith, left unsolved by the nitro- 

 muriatic acid. This portion of the stone, when dried upon the sand bath, was 

 found to weigh 128.28 grs. Of this 114.12 were reduced by a red heat to 

 102.47. Hence, as 114.12 : 102.47 : : 128.28 : 115.18, the exact weight of the 

 portion of the stone left undissolved by the acids. 



The 102.47 grs. which had been exposed to heat were mixed in a platinum 

 crucible with three times their weight of carbonate of potash, and fluxed at a strong 

 red heat for twenty minutes. The fused mass was then transferred, by repeatedly 

 boiling it with water, from the crucible to a porcelain capsule, dissolved in a 

 dilute nitro-muriatic acid, and then cautiously evaporated to dryness. The dry 



