3 1 8 The Vitriol 



Copper furnifhes a remarkable experiment to 

 this purpofe, upon properly evaporating the green 

 water remaining from a folution of filver precipi- 

 tated by copper ; but iron more clearly, as I have 

 found after employing the greateft degree of care, 

 having more than once obferved, that working it 

 with oil of vitriol for vitriol? there ever remained 

 fomething oleaginous, that could not be made to 

 moot, and only became a dried mafs : and as I 

 did not over, but rather under dofe the iron there- 

 with, I at firft began to fufpect the purity of my 

 iron ? and being well apprized that many forts of 

 iron, particularly the carl, though I never em- 

 ployed fnch in this procefs, nay, other common 

 iron, may contain fomething extraneous, as com- 

 mon fulphur, which is no conftituent part thereof, 

 fometimes lodges therein, I employed the bell Stey- 

 ermarck fteel, as pure an iron as is poffibly procu- 

 rable, and yet even this fort manifeiled the fame 

 thick oleaginous liquor that common iron did, and 

 became dry in the fire, but fmeary again in the 

 air. 



After the arfenical matters, and the metals, the 

 vitriolic? and the like mixtures, are what are pro- 

 cured from pyrites? either with or without fire, alfo 

 from calamy-ftone, and the foflile Hungarian vi- 

 triol? as thus, take vitriclated pyrites-mixt- work? 

 as of BraunfdorfT, and the Rothe-grube ; alfo vi- 

 triolated Hefftan earth, burnt foffile calamy, Hun- 

 garian vitriol, without picking out the green pieces ; 

 taking the white amonglt them as they come to 

 hand, diffolve each in water, filtrate, boil, and 

 evaporate, and fet to moot feveral times again ■? 

 then commit what remains, which will prove high- 

 ly oleaginous, to the fofteft degree of a fponta- 



neous 



