t240 



ILLUSTRATIONS OF THE 



foft and miilU able *. The Siberian fpecimen 

 clefcribed by Pallas, is alfo very large ; it is foft 

 and malleable, and full of round cavities, con- 

 taining a fubftar ce, which, on examination, has 

 been found to be chryfolite -j-. Now, it is cer- 

 tainly quite impoffiblc, that^ in an artificial fu- 

 fion, fo much chryfolite could have come by 

 any means to be involved in the iron ; but, if 

 the fufion was natural, aad happened in a mi- 

 neral vein, the iron and the chryfolite were both 

 in their native place, and their meeting toge- 

 ther has nothing in it that is inexplicable. 



212. Some circumftances in the defcription 

 of the fpecimen in South America, fuoji as the 



^ 



impreffions of the feet of men and of birds on 

 its furface, are not to be accounted for on any 

 hypothelis, and certainly require more care- 

 ful inve {ligation. It is faid, that this iron is 

 very little fubje6l to ruft, and the analyfis of i| 

 piece of it by Proust makes it probable, that 



it owes this qualit 



its union with nickel J. 



It 



appe 



alfo, that the country of Chaco, 



where this fpecimen was found, affords many 



others of the fame kind, one of which is men- 



tioned in the defcription above referred to. That 



country 



* Phil. Tranf. 1788. p. 37. alfo p. 183, &c. 



4- Kirwan's Mineralogy, vol. ii. art. Native Iron. 



t Annales de Chimie; torn. xxxv. Meffidor, p. 47» 



