i8S Of the Arsenic 



changes to a white fpongy froth and wool, a philo" 



fopbical cotton. 



It turns copper not only of a higher yellow, 

 whence the metal happens to be diftinguifhed by 

 the appellation, prince' s-metal, or rather bronze- 

 metal, at leaft with us Germans, but it alfo renders 

 it more brittle than the foflil calamy does ; hence, I 

 fuppofe the proper tinging fubftance, which in the 

 fofTile calamy is blended with an earth, fomething 

 ♦adventitious and foreign, not entering along with 

 the tinging parts into the body of the metal, is in- 

 corporated in another metallic brittle- making fub- 

 ftance, namely, lead. 



For, (i.) the fort of ore at the Hartz, whence 

 our zink is derived, is never without lead-ore, nay, 

 is principally found to confift therein; (2.) from 

 foflile calamy (for which end I have employed the 

 Spanifh) and lead-glitter, I have produced a formal 

 beautiful zink, which, in any other method, would 

 not fucceed, at leaft not with me. Nay, it is no 

 uncommon thing to find calamy and leadglitter to- 

 gether in a vein, a fample of which I can fhew from 

 JBrilon in Weftphalia : and it will be plain fromcon- 

 fidering but a little attentively, the loamy earth near 

 Ulkos in Poland, wherein lead-ore lies irregularly 

 huddled together, to which might be added other 

 circumftances *, that there is fomething fcparable 

 from the zink-, which is not indeed pure lead, tho' 

 approaching nearer to lead than to zink. 



As I am perfwaded that this tinging fubftance is 

 lodged m other earths and liones, befides that called 

 calamy, at the brafs-huts, fo there are alfo other 

 metals, befides lead, out of which it may be educed ; 

 at leaft I have found, upon working tin along with 



acer- 



