MODE VI. SERPENTINE. 



345 



" M. Chenevix, the chemist, who has em- 

 ployed himself in a succession of analyses of 

 magnesian rocks, found that serpentine and ol- 

 lite are composed of the same elements; and 

 that, according to a medial sum of many ana- 

 lyses, they contain, silex 28, argil 23, magnesia 

 34, oxyd of iron 4, water 11."* 



The name, serpentine seems to have been de- 

 rived from the Italians, who however applied it 

 in differently to several substances; as black 

 porphyry was called serpentino nero, and the 

 green porphyry serpentino antico^. The name, 

 which was vague at first, was afterwards con- 

 fined to this magnesian rock, to which it is most 

 strictly applicable, from the variegation and 

 unctuous appearance of the colours. 



Ferber has minutely described several of the 

 Italian serpentines, particularly that of Impru- 

 neta, near Florence. The colours are white, 

 red, black, yellow, and green ; sometimes uni- 

 form, sometimes intermingled. It is often inter- 

 sected by small veins of asbestos, and sprinkled 

 with an unctuous micarel, of a greenish silvery 



* Patrin Min. i. 177. 



t Wall. i. 432. It is singular that this truly learned author 

 should have followed the common error concerning the ophites of 

 Pliny. 



Name. 



Italian. 



