14 TRAVELS THROUGH 



8. White, compact, and fine calcareous fpar j 

 or rather limeftone with mica and fherl-cryftals, 

 both of different colours. This is probably be- 

 longing to a vein (gang-arth)> and feems to fup- 

 port my fuppofition of veins under ground at Vefu- 

 vius. They appear in fragments of different big- 

 nefs , fome as large as a man's head. Neither I, 

 nor Mr. Guettard, could imagine thefe Hones to be 

 really thrown out of Vefuvius; we conjectured 

 them to have been broken at monte Somma, or elfe- 

 where. But having found monte Somma deftitute 

 of fuch ftones, and plenty of them fcattered all 

 around Vefuvius, we changed our opinions ; and 

 this the more fo, as we happened to fee in Don 

 Valenclanis magazine, at Portici, fome fragments, 

 which vifibly had been affected by fire. 



9. The mica, or glimmer, in this calcareous 

 fpar, is more or lefs hard, fofr, and fimilar to talc. 

 Its colour white transparent, white argentine, and 

 then fat to the touch ; yellow, green, dark-green, 

 blackim. Its texture lamellated. 



10. Adherent to fuch a fpar, foft, loofe, and 

 fat glimmer; of a fplendent blofTcm 1 colour, fimi- 

 lar to molybdana. In Mr. Eottfs collection. 



1 1 . The Jherl cryft alii fattens of this calcareous 

 fpar, (n. 8.) are cofnmonly found in its holes, 

 which they cover all around. According to my 

 ppinoin, they feem to have belonged with the mica 



and 



