208 Of the Arsenic 



the filver in the lead- working, the copper in the 

 Mack-copper- working. 



(2.) Sulphur and arfenic have no other affinity 

 than that they are the two grand caufes of minera- 

 lifation, or of reducing metals to their ore-ftate, 

 and that only in regard to iron and copper : but if 

 any thing mud be put on a footing with arfenic, it 

 muft needs be quickfilver rather than fulphur. 'Ar- 

 fenic is a femi-meta!, quickfilver not much other. 

 So that the queftion is reduced to this point, whe- 

 ther the arfenic will not alfo, like quickfilver, bear 

 the being combined and carried over along with the 

 fulphur : and for this the fandarach affords a plain 

 anfwer, and an ocular demonftration •, as in this 

 cafe, the carrying over of the arfenic by the fulphur, 

 happens as in the manner of quickfiver, that the 

 third body, namely the fandarach, educed from 

 thefe two, may be confidered as 2. phil of ophical cin- 

 nabar. 



Moreover, Arfenic holds firmer ft ill in its pyrites, 

 when either by accident, or with defign, it happens 

 to cake or run together with its accompanying iron- 

 earth *, which (hews it would ftand the fire, and 

 that it wants fomething in iron for that purpofe. 

 The relation of iron to other metals has been 

 (hewn above, chap. iv. by the magnet. 



(3.) 'Tis no wonder, that arfenic, in its fepa- 

 rated ftate, can fo Wry difficultly be again intro- 

 duced into fmelted iron ; even as difficultly as it 

 is to exhibit a fulphur- pyrites by art ; feeing it de- 

 pends on a due appropriation of the iron, and the 

 properly exhibiting its earth-form. On which en- 

 cheirefes and circumftances, many, anu thofe the 

 moil important combinations, c'fpecially in the imi- 

 tations 



