REPORT ON MINERAL VEINS. 5 



mining. He had the rare merit of emerging from the mists and 

 clouds of an absurd school of philosophy, which had till then 

 obscured the objects which it pretended to illustrate ; and he 

 first subjected them to inquiries prompted by sound reason and 

 just views of nature. 



His writings were numerous, and in such pure Latin that 

 they are said to be entitled to a place among the classics. He 

 treats of veins in a work called Bermannus, but more particularly 

 in the third book of his great work De Re MetaUica. 



Agricola being held to be the first who has written anything 

 certain on the formation of veins, and his theory of the manner 

 of their being filled up having, with some modifications, been 

 for a long period generally received, and in part even adopted 

 by Werner, I shall commence from his time the notice of the 

 opinions promulgated by various writers antecedent to Werner 

 and Hutton. 



Some have maintained. That veins and their branchings are 

 to be considered as the branches and twigs of an immense trunk 

 which exists in the interior of the globe : 



That from the bowels of the earth metallic particles issued 

 forth in the form of vapours and exhalations through the rents, 

 in the same manner as sap rises and circulates in vegetables. 



This speculation was proposed by Von Oppel, captain-ge- 

 neral of the Saxon mines, who wrote in 1749. He was a skilful 

 miner and an accurate observer; and it is singular that this opi- 

 nion is not consistent with most that he has elsewhere said on 

 the subject, which generally rather agreed with the views which 

 were adopted by Werner and others. 



Henkel, who wrote in the early part of the seventeenth cen- 

 tury, and who has been held to be the father of mineralogical 

 chemistry, first attributed the formation of the contents of veins 

 to peculiar exhalations : he supposed the basis of each metal 

 and mineral to have existed in the substance of the rock, and 

 to have been developed by a peculiar process of nature. 



Becher about the same time supported very similar views. 

 Stahl, who commented upon the writings of Becher, had ad- 

 vanced a somewhat similar opinion; but he afterwards rejected 

 this theory, and considered veins, as well as the substances of 

 which they are composed, as having been formed at the same 

 time with the earth itself. 



Zimmerman, chief commissioner of mines in Saxony, who 

 died in 1747, had an idea that the variety of minerals contained 

 in veins had been produced by a transformation of the sub- 

 stance of the rock. 



Charpentier, in 1778, supported nearly similar opinions, and 



