13S A SYSTEM OF 



but lefs pure, it diflblves copper, iron, 

 zink, and the regulus of antimony : the 

 copper is however more eafily diflblved, 

 when it is in form of a calx, as the calces 

 of quickfilver and cobalt like wife are. 



7. It unites with filver diflblved in aqua- 

 fortis, and with lead diflblved in aqua- 

 regia, falling with them to the bottom, in 

 form of a white fpongy mafs. This preci- 

 pitation, expofed to the fire, ftill retains 

 the acid, and melts with it into a glafly 

 fubltance, which does not diflblve in water. 



8. It is apt to attract the humidity of the 

 air, and to promote the decaying of thofe 

 dry fubftances, with which it has been 

 united. 



g. Mixed with the fpirit of nitre, it makes 

 the fo called aqua-regia, which is the true 

 liquid menftruum for gold. 



This acid feems alio, on certain occa- 

 fions, to have got loofe from thofe fub- 

 ftances, with which it has been originally 

 united in the earth : the fat ammoniacum 

 naturale at Solfatara in Italy, and the horn 

 filver ore (clxxvii.) appear to be proofs of 

 this, as they feem to be the products of 

 time. 



SECT. CXXVIII. 



l. Mixed or fatiated acid of fea-falt, Acidum 



falis hcterogeneis faturatum. 

 A. With earths, I'erris faturatum, 



1 . With a calcareous earth, ferrd calcared 

 faturatum : Sal ammoniacum fixum. 



This iomewhat decays or attracts the 

 humidity of the air: it is found in 



abundance 



