310 The Vitriol 



terfperfed with pyrites, is a fort, which directly up- 

 on burning (for it proves too poor for making ful- 

 phur) has been elixated for vitriol, yet with me it 

 has net yielded enough ; though the reafon of fuch 

 pyrites giving vitriol without air, barely by means 

 of the fire, be, that the iulphur therein finds a pre- 

 pared corporal iron, wherein its acid fait may di- 

 rectly lodge, yet the cafe is certainly different in a 

 pure, firm pyrites, the iron- earth of which is not 

 thus prepared. 1 have, however, procured a little 

 of fuch vitriol, and the fmali fhare of vitriol from 

 all forts of pyrites, fhew the poffibiliry of the 

 thing. 



But though I could not fucceed in the manner I 

 had been directed at the vitriol-huts, yet I find no 

 reafon to deny that vitriol may be procured from 

 burnt pyrites, without a previous expofure to the 

 air, efpecially when I confider the peculiar experi- 

 ment of the vitriol from calamy : beiides, that from 

 the mifcarrying in the fmali way of proof, we can- 

 not queftion the truth of the large way of working 

 (as, in other refpects, the conclufions from proofs 

 in the fmali to yields in the large way, are often 

 very fallacious) as I have experienced how difficult 

 in general it is to afTay pyrites for vitriol, without 

 employing large heaps for the purpofe. 



Yet k may be made appear probable, that the 

 air .contributes fomething here, when we confider 

 the nature of fire, as yielding no Maine without air, 

 nay, deriving by and from it, together with the 

 fatty 3 foot-particles, its needful fuel and pabulum ; 

 and thus the air is at leafl an indifpenfible inft ru- 

 xntrx in vitriolifation. But be this as it may, fuch 

 pyrites directly elixated upon burning, when, to be 

 further worked for vitriol, is co be {hoc in the air, 



and 



