from the Pyrites! 301 



fort, are Found not only radiated and ftellate bails, 

 which are at leaft of a different texture from the 

 globular, but alfo cubical ; which, in regard to 

 their metal earth, differ remarkably from both the 

 former, and are not without fome copper ; though 

 the ground and bottom, where they lie intermixed, 

 nay compreffed together, be one and the fame. 



In the territory of Boll, are whole tracts ftrewed 

 with various forts of pyrites, as the periwinkle, 

 mufcle, nut, globe, and radii kind ; and fuch py- 

 rites generally agree in mixtion, like that fort in, 

 and under the under-turf earth, and of like figures, 

 and neither coppery nor arfenical ; and yet I have 

 had inilances, though rarely, of pyrites, containing 

 fome little arfenic and copper, and yet produced in 

 one neft and matrix, near and among the former ; 

 a thing not to be wondered at, as fuch mineral pro- 

 ductions are fubject to many incidents, which in- 

 terupt their growth •, nor is it at all furprifing to find 

 pyrites fimilarly, and difTimilarly vitriolife. The 

 globular refolve fooneft and with the greateft eafe ; 

 the radiated or conical more difficultly, and tho* 

 they mould foon enough refolve into radii or cones, 

 yet they here remarkably flop fhort, before they 

 fully change to vitriol. The conical confiding of 

 a number of cones or pyramids put together, with 

 their points concurring in the middle, and their 

 bafes again projecting into fhort, either fharp or 

 obtufe, and thefe again partly in broken angles ; 

 and where joined together, they are, doubtlefs, 

 not fo clofe and firm, as in the remaining parts. 



That the air is the genuine and absolutely ne- 

 ceffary inftrument in litriolifation we have already 

 fhewn, and it may be fummarily confirmed from 

 this con h deration, that pyrites , which remain un- 



refolved 



