io ©F t$e ^ec&am'eal 4)*fgf ne of 



exper.. m. 



TIs obferv'd by Refiners, Gold- 

 fmiths and Chymifts, that 

 Aqua Forth and Aqua Regia which 

 are Corrofive Menftruums , diflblve 

 Metals, the former of them Silver, 

 and the latter Gold 5 much more 

 fpeedily and copioufly when an ex- 

 ternal heat gives their inteftine mo- 

 tions a new degree of Vehemency 

 or Velocity, which is but a mechani- 

 cal thing* and yet this fuperadded 

 rneafure of Agitation is not onely 

 in the abovementiond Inftances a 

 powerfully affiftant Caufe in the So* 

 lutions made by the lately mention'd 

 Corrofive Liquors^ but is that with- 

 out which fome Menftruums are not 

 wont fenfibly to corrode fome bo- 

 dies at all ? as we have tried in keep- 

 ing Quick-filver in three or four 

 times its weight of Oyl of Vitriol 5 

 fince in this Menftrtium I found not 

 the Mercury to be diffolved or cor- 

 roded, 



