ON A NATURAL SYSTEM 



The combination of gold with fulphur, by the 

 intermedium of iron ; is not yet made fuflicient- 

 ly evident; for that which is found in pyrites 

 feems to be rather mixed than diilblved; as in a 

 folution of pyrites, in the nitrous acid, the 

 gold is depoiited in molecules, not in powder, 

 but diil'ering from each other both in lize and fi- 

 gure *. 



As to 7.inc, that metal appears in the pfeudo 



galena to be joined T uith iulphur by means of 

 iron. 



CL. Miner alifing Acids. 



OF mineralifing acids there are fevcral, asthd; 

 vitriolic, muriatic, phofphoric, aerial, and pro- 

 bubly the arfciiical. 



} CLI. Vitriols. 



VITRIOLS of copper, iron, and zinc, are the 

 fpontaneous productions of nature. Combina- 

 tions of the fame acid with lead, niccolum, and 

 cobalt, are likewife fometimes found ; and they 

 feem generally to be the refult of decompofed 

 mineralifations. 



ictii, 



* EfTayi, vol. ii. p. 412. 



\ JbiJ.p. 329, an 



