in the Pyrites. 235 



ly gone off. Melt this filver once more, nay 

 twice, with a little borax and falt-petre, and it 

 will prove as fine and ductile as a tefted filver. 

 Then granulate and difiblve it in aqua fortis, and 

 you will have a number of fmall black flocks, 

 which being melted, prove to genuine gold. Re- 

 peat this with the fame filver afecond and a third 

 time, and you will always procure fome black 

 geld ca!x. in the fir ft procefs, the particles, 

 which are proximately fitted to become gold, be- 

 gin to be perfect, and fall down as fmall black 

 flocks. Jn the fecond, there are fome more pre- 

 pared and perfected •, and in the third, none at 

 ail: when it appears, that the particles, fitted to 

 become gold, are by the two firft operations 

 quite exnaufied, or drained out of the filver. 



c Here it may be objected, that the regulus of 

 antimony (regule de Mars) has produced or 

 educed this black calx from itfelf: if fo, there 

 muft as much be procured in the fecond and 

 third operations as in the firft : whereas in the fe- 

 cond, there is not* fo much as in the firft, and in 

 the third, none at all. To this add, that we 

 very often meet with grown, native gold in the 

 earth, much paler than a fine fort mould be, yet 

 without yielding the leaft filver, and which, by 

 a repeated fmeking, begins to become perfect, 

 and to attain its due colour. Thus we find in 

 filver a matter that turns to gold •, and in gold, a 

 a pale (blanchatre) matter, which by the fire gains 

 the genuine gold colour. Thefe are the two mat- 

 ters, which are a middle metal between gold and 

 filver, but which remain not long in this ftate, 

 being by each fm citing brought ft ill more and 

 more to the perfection of gold V 



* Mem. fcCi Tan. 1709. p. 141, feq. 



T*1 *„ 



j. ms 



