x The Author's Preface. 



only in the fixteenth century : It appears by the 

 Friberg chronicle *, there were above one hundred 

 fuch works, which yielded quarterly, in profits 

 to the adventurers, for one .mine-action (accord- 

 ing to the then divifion into thirty two fliares) 

 at the leaft ten ; mpft of them above thirty and 

 forty ; many above fifty and one hundred ; nay, 

 fome, above two hundred ; and the ThurnhofF 

 and Hohebircke in particular, above three hundred 

 rix- dollars. And this we mould well obferve, as 

 -it fhews, that not only one or two mines, are 

 thus valuable, but generally all of them ; and 

 obviates an objection, as if all thefe treafures 

 were now quite exhaufted : which is far from 

 -being the cafe •, our hopes being ftill as extenfive, 

 as there are grooves and mines to work, and field 

 for receiving fuch a vaft number of (hafts and 

 levels f : not to mention entire, unmeafured veins, 

 which are fo much frefh and unoccupied trea- 

 fure. 



Further, the accounts and inftances we have 

 of extraordinary rich ores in fome works, mould 

 prevail with us to view the bufinefs of min- 

 ing with other eyes than we commonly do. 

 At Schneeberg in 1478, a rich filver vein was 



dif- 



* P. 434. f Shafts are pits, fometimes perpendicu- 



lar, fometimes oblique, funk upon a vein . Levels are hori- 

 zontal pafiages worked thro' a mountain, both for draining the 

 mine of its water, landing the ore to the day, and for convey* 

 inS in air. And for both theft laft ufes lhafcs alio fervc. 



