2<?4 W* Vitriol 



time the fuiphur, as is the way at the fulphur-Ivjts ; 

 or, out of a wind-furnace, whofe flame plays on 

 the pyrites lodged in an adjoining roafting furnace : 

 or on a roafting- bed, where the pyrites may be belt 

 thoroughly burnt, or calcined : the firft method is 

 that ufed at Friberg, for the fake of preferving the 

 fuiphur. 



i 2. The fire is the next inftrument ; which, if 

 not entirely fufficient of itfelf, yet is ferviceable for 

 the firft opening and preparing the pyrites, nay, 

 indifpenfibly necefTary for many forts of pyrites, 

 which would not otherwife (hoot in the air. It is 

 indeed of itfelf alone fufficient, nayabfoluteiy need- 

 ful, for exhibiting vitriol from other vitriolejcent 

 bodies, particularly foffil calamy, from which, 

 without burning, there is no hope of fuccefs •, and 

 tho s the burnt calamy be never fo long expofed to 

 the air, yet it would not, for all that, receive the 

 more vitriol; which is fomething equally peculiar; 

 as is alfo in this very procefs and act of burning, 

 the fulphur-production. The burnt, or calcined 

 pyrites do alfo, after burning or roafting, without 

 a previous expofure to the air, yield, by the ufual 

 way of elixation, a vitriol; but not generally (the 

 reafon of which difference I have not yet fufficient- 

 ly difcovered) nor fo richly, as when the air has 

 previoufly forfome time thoroughly worked them : 

 but this and a great deal more muft be attentively 

 Confidered. 



As (i.) In what the bufinefs of vitriolifation con - 

 fills. (2.) What is procured from it. 



As to the vitriolifation itfelf, it depends on va- 

 rious circumftances, particularly the following. 

 The air is the principal agent here, and contains 



two 



