Analysis of Meteoric Iron from Tennessee. 355 



It turns out therefore, to be a portion of the mass described by 

 Dr. Troost in Vol. xxxviii, p. 250, of this Journal. Having been 

 presented by Dr. T. with several fragments, as illustrative of the 

 portion in his hands, I found on comparing them with the spe- 

 cimen sent by President Easterbrook, that the latter differed very 

 much from the former, in external appearance. Unlike to them, 

 it was to a degree, free from the plumbaginous and pyritous ad- 

 mixtures with which they abound. It agreed with them how- 

 ever, in possessing a coarsely crystalline texture. Its proportion 

 of nickel falls much below that quoted by Dr. Troost ; but this 

 is a circumstance which I have found to hold true in the Texas 

 iron, wherein my experiments have proved the nickel to vary from 

 3.2 to 9.6 per cent. The specific gravity of the mass was 6.222. 



I. Ten grains were treated with nitro-hydrochloric acid. The 

 metal was rapidly taken into solution ; but a blackish residuum 

 remained. This was treated by itself, with heated nitro-hydro- 

 chloric acid for several hours. The quantity was thereby redu- 

 ced ; but a few black grains (of the size of fine-grained gunpow- 

 der) together with numerous shining scales, still remained in the 

 fluid. These were well washed and dried. They weighed 0.01 

 gr. The acid solutions were mingled, and precipitated by am- 

 monia, in large excess. The fluid stood along with the precipi- 

 tate for six hours, at a temperature of nearly 100°. The peroxide 

 of iron was then separated, and thoroughly washed for several 

 hours with tepid water. The washings and the original ammo- 

 niated liquor were mingled and boiled ; after which they were 

 transferred to a glass bottle, and decomposed while hot by potassa. 

 The clear liquid was separated after twenty four hours, by filter- 

 ing (the hydrosulphate of ammonia, when added to it, produ- 

 ced no change of color). The precipitated oxide of nickel was 

 ignited, and weighed 0.6 gr. The peroxide of iron after ignition, 

 weighed 13.4 grs. We have then, 



Iron, - - . - 9.380=93.80 p. c. 

 Nickel, - - - - .466= 4.66 p. c. 



Undissolved, - - - .010= 0.10 p. c. 



A second and parallel analysis was conducted upon 30 grs., the 

 results of which were as follows : 



Peroxide of iron, 40.30=Iron, 28.210=94.033 p. c. 



Protoxide of nickel, 1.68=Nickel, 1.333= 4.444 p. c. 



Undissolved, 0.03=Undissolv'd, .030= 0.1,00 p. c. 



