142 Prof. Wohler and Dr. Atkinson's Analysis of the 



It was seen in brilliant shining lamellse on boiling out the me- 

 teorites with hydrochloric acid. 



The chief mass consists of two kinds of silicates, of which one 

 is decomposed and gelatinized by hydrochloric acid, and the 

 other is not decomposed. 



A microscopic examination showed that most of the minerals 

 which occur in rounded pai'ticles on the dark mass of the me- 

 teorite are silicates undecomposable by acids, while the mass of 

 the stone is chiefly made up of decomposable constituents. Ex- 

 clusive of the determination of the quantity of hydrogen evolved 

 on treating the meteorite with acid, three kinds of analysis were 

 made. One by fusing the meteorite with carbonate of soda, 

 from which the quantity of silica was found to be 41 "62 per cent. 

 A second was made with hydrofluoric acid, in which the quan- 

 tity of silica estimated from the difference was 43'94 per cent. 

 This excess of 2'32 of silica is explained partly from the unequal 

 mixedness of the meteorite, partly from the unavoidable loss in 

 so many constituents, which of course fell on the difference, and 

 partly from the phosphorus, sulphur, and oxide of chromium, 

 the quantities of which were too small to be determined with any 

 degree of accuracy. In this manner, by the usual methods, the 

 meteorites were found to contain in 100 parts the following 

 constituents : — 



Metallic iron . . . 18-10 



Nickel 1-45 



Cobalt 0-05 



Graphite .... 0-25 



Magnesia . . . . 23-83 



Protoxide of iron . . 4-61 



Protoxide of manganese 0-28 



Alumina .... 3-15 



Lime 1-80 



Soda 2-34 



Potassa 0-50 



Sulphur . . ,~\ 



Phosphorus . . I ^g.g^ 



Oxide of chromium [ 



SUica ... .J 



100-00 

 An experiment was made to separate the two kinds of silicates. 

 The finely-powdered meteorite was heated for a long time with 

 strong hydrochloric acid. The residue was well washed out, and 

 boiled repeatedly with carbonate of soda. The insoluble residue 

 amounted to 30-48 per cent. (In a second experiment, where 

 the mass was not boiled so long with carbonate of soda, 36 per 

 cent, was obtained.) 



