66 ©f tlje ^et^anical ©ngjtae of 



urn were corroding foine ftubbora 

 metal or mineral. And this Expe- 

 riment I the rather mention, becaiife 

 it may be of ufe to us on divers other 

 occafions. For elfe 'tis not the 

 onely, though it be the remarkableft, 

 that I made to the famepurpofe. 



EX PER. IX. 



FOr, whereas Aqua Fortk or Aqua 

 Regis , being pour'd upon Filings 

 of Copper 5 will work upon them 

 with much noife and ebullition, I 

 have tried, that good Spirit of Sal Ar- 

 moniac or Urine, fyeing put upon the 

 like Filings , and left there without 

 flopping the Glafs, will quickly be- 

 gin to work on them, and quietly di£ 

 folve them almoft as water dif- 

 folves Sugar. To which may be 

 added, that even with Oyl of Tur- 

 pentine I have D though but (lowly, 

 diflfolved crude Coppery and the 

 Experiment feemed to favour our 

 Conjefture the more 5 becaufe ha- 

 ving tried it feveral times , it ap- 

 peared, 



