29*} The Vitriol 1 



tirely in yield, namely, having neither copper nor 

 arfenic, no not in the lead quantity, but only ful- 

 phur and iron along with the unmetallic earth ; 

 alfo one and the fame figure, colour, &c. yet one 

 fort ' y viz. that of Almerode in HefTe, as alfo the 

 fort from Altfattel by Egra run exceeding quick to 

 this metallic fait •, another fort, as that from Boll 

 and Toplitz, very difficultly, nay, if not beat very 

 fmall, and buried in the earth, not at all. Amidft 

 thofe contradictory inftances, I have fometimes 

 dropped the copper, and afligned as caufes, the 

 figure, the colour, and fometimes the texture and 

 the grain of the pyrites, fometimes again the arfe- 

 nic, at other times the unmetallic earth, fometimes 

 the bed, and the adjoining or interfperfed mine- 

 rals, and fometimes one of thefe circumftances 

 only, fometimes two or three at a time; or rather, 

 as colours and figures are not caufes fo much as 

 figns only of thefe caufes; from the figns I have 

 endeavoured to come at the things themfelves, and 

 from their difference, was obliged to abide by the 

 contents, the mixtion and texture of the pyrites. 



From the arfenic there accrued a great degree of 

 probability, that as the white pyrites does not at all 

 vitrioUfe, its arfenic, according to its greater or 

 lefs quantity, muft at leaft be the reafon, why the 

 yellowifh often undergo vitriolifation, and the yel- 

 low always with difficulty, or not at all -, did not 

 that fort, which is without any arfenic, and yet re- 

 maining unvitriolifed as the other, ftand in the way: 

 The unmetallic earth, which is two- fold, either 

 flinty or calcarious, afforded no light in the cafe. 

 From the texture, one pyrites appears not only 

 denfer and more fine-grained than another, but has 

 alfo, though no other mixtion- materials, yet ano- 

 ther mixtion-guife, as well in proportion as in ela- 

 boration 



