612 



APPENDIX. 



may generally be considered as indicative of the presence of 

 these gems. 



" Having thus examined the strata upon the shore, I 

 walked into the country for about two miles, but could ob- 

 serve no trace of the serpentine, or marble, or talcaceous 

 schistus j but in several places I observed the hornblende rock. 

 I ascended a hill a few hundred feet high j upon the side of 

 it were masses of hornblende rock and gneiss scattered about, 

 but towards the summit it was entirely composed of schistose 

 quartz. This is a rare rock in Scotland j nor has it been 

 observed but in a very few places upon the Continent." 



o 



ffi 



& 



No. VI. Further illustrations of Miagite and Niolite. 



[Translated from Faujas, Essai de Geologic, Paris 180Q, 

 tome ii. p. 679.] 



ORBICULAR GRANITE OF CORSICA ; 

 Discovery of the Site of this Stone. 



In 1785 was discovered in Corsica, on a small eminence 

 with a level summit in the plain of Taravo, an insulated and 

 rounded, but at the same time unparalleled block of rare and 

 extraordinary granite with globular crystallisations, which 

 deeply excited the curiosity of naturalists. 



If, on the one hand, this discovery was interesting to mi- 

 neralogists; on the other, geologists readily comprehended 



