in /& Pyrites, 117 



larger; whereas the pyrites iron-ore, that runs from 

 above inwards, lofes itfelf more and more, upon 

 the encreafe of the former. Whence it may be 

 probably conjectured, that iron and copper are, in 

 regard of their proximate metallic ground-earth, if 

 not one and the fame, yet greatly refembling each 

 other, and differing only in the degrees and periods 

 of coction, maturation, and exaltation: particu- 

 larly, that thofe particles, which, in the iron-py- 

 r\tes, were to be carried no higher than to the form 

 of iron, are, in the copper- pyrites, on the contrary, 

 or copper-ore, to be railed to a higher and nobler 

 form ; that is, to that of copper, as what requires a 

 different and a more thorough degree of coction 

 and maturation. 



What confirms the conjecture of the iron and 

 copper pyrites having the fame original (in particu- 

 lar, that the one is derived from the other) is, that 

 the copper-pyritx feldom begin from the day, or 

 beneath the under- turf earth ; whereas the iron- 

 pyrit<e commonly manifeft themfelves there ; 

 nay, where the former happen to appear foon 

 (which neverthelefs is rarely obferved) the lat- 

 ter do not only equally as foon manifeft themfelves 

 in huge beds, ft ock- works, bellies, and nefis, but are 

 alfo gradually accompanied by the former. Yet all 

 this does not fully fatisfy the query •, the nature of 

 the deepeft, that is, of the fole or bottom of the 

 mine, as far as it has been funk, being befides. to 

 be confidered. 



Now, here again we are not to doubt, but that 

 iron-pynt<e lodge alfo at the greater! depth, even . 

 in the center of the earth •, it being pofiihle, that 

 the fame caufes, that operate near the furfacc, 

 fhould alfo exift at the greateft depths. Our ex- 

 perience and knowledge are, however, not fuffi- 



I 3 ciently 



