of 5>eat anD €olD* 25 



rates upon it* And the Fumes of 

 Le*id have beenobferved fometimes 

 ( for I have not found the Effe& to 

 fucceed always) toarreft the fluidi- 

 ty of Mercury, which change is fqp- 

 pofed to be the effeft of a Potential 

 Coldnefs belonging to the Chymifts 

 Saturn in reference to fluid Mercu- 

 ry, though it have not that operati- 

 on on any other liquor that we know 

 of. 



And laftly, (for I would not be 

 too prolix) though Nitre and Sal 

 Armoniac be both apart and joynt^ 

 ly Cold in reference to Watery and 

 though, however Nitre be throughly 

 melted in a Crucible, it will not take 

 fire of it felf, yet if, whilft it is in 

 Fufion, you (ball by degrees caft on 

 it fome powder'd Sal Armoniac, it 

 will take fire and flafti vehemently, 

 almoft as if Sulphur had been in- 

 jected. 



But 



