reded , though I kept it a long time 

 in the Cold; Whereas,, when the 

 Oyl of Vitriol was excited by a 

 convenient heat , (which was not 

 faint} it corroded the Mercury into 

 a fine white Calx or powder, which, 

 by the affufion of fair water, would 

 be prefently turned into a yellowilli 

 Calx of the colour and nature of a 

 Turbkh. I remember alfo, that ha- 

 ving for trials fake diffolv'd in a 

 weak Spirit of Salt, a fourth part of 

 its weight of fine Cryftals of Nitre, 

 we found, that it would not in the 

 cold C at leaft during a good while 

 that we waited for its operation) dif- 

 folve Leaf-gold 5 but when the Men- 

 firuntn was a little heated at the fire, 

 the Solution proceeded readily e- 

 oough. And in fbme cafes , though 

 the external heat be but fmall , yet 

 there may intervene a brisk heat, and 

 much cooperate in the diffolution of 

 a Body 5 as^ for inftance, of Quick- 

 (ilver in Aqua Fcrtif. For it is no 

 prodigy to find , that when a full 

 proportion of that fluid Metal has 



been 



