160 QUARTERLY JOURNAL. 



spar, interspersed with datholite and pieces of pure native copper 

 these have the same evidences of igneous origin as the trap rock 

 There is also a vein of phrenite 4 feet wide, and every crystal 

 which had a crystal of copper attached. In short, every vein tha 

 is found or opened in that region, (no matter what the base is 

 contains more or less silver. But the best mine yet found is th 

 ore on Eagle river; the vein is from 1 to 13 feet wide, and the vein 

 contain metallic copper and silver; amygdaloidal globules wit 

 crystals of copper and particles of silver; and frequently we sa\ 

 pure copper and pure silver in the same globule. We also fin* 

 leaf copper and leaf silver; and octahedral crystals of silver 

 (Dr. J. here exhibited fine specimens of all these minerals.) Thi 

 great copper rock found on the Ontonagon river had serpentin 

 attached to it; and the only copper we find that is mixed up witi 

 serpentine is on Isle Royal, whence that great rock must have be© 

 carried on a raft of ice and landed above the rapids, as there is m 

 copper in situ within miles of where it was found. In Nova Sec 

 tia the copper that is found is just where the trap goes through tb 

 sandstone, and igneous action has probably reduced the ores t 

 native copper. But the copper on Lake Superior, I confess, 

 think to have been part of the ijnmary copper of the globe, (i 

 Dr. Houghton also does,) brought up from the molten mass by ti 

 trap rocks. It is a badly wrought slag; as if old Pluto had 

 separated all the metal from the slag before he let the trap n 

 push it up for the service of man. There is one vein of copp 

 11 feet wide and one mile long, that will repay all the outlay ( 

 the Company. The Cornish miners th€re have sunk four shaf 

 on the banks of the river, intending to work the mine under tl 

 river. One shaft is already 60 feet, another 40, another 30 fei 

 deep — all done by hand power. The deeper they go the rich* 

 the mineral is; and it contains about one-fourth silver. Col. Gk 

 tiot has the superintendence there. And in working one sing] 

 exploration shaft at the Eagle river mine, the metallic conteni 

 brought out by hand are worth $30,000 ! The rock is amy§ 

 daloidal, and blasts very easily; it does not take more than twer 

 ty minutes to make a hole for a blast. There is no water in tb 

 shafts at all, although they have worked down 25 feetbelowthebe 

 of the river; and instead of the water of the river troubling then 

 when the dam is built it will be their greatest friend. The watf 

 wall raise the ore from the mine, pound it, blow the blast for th 

 smelting furnace, and saw the wood for the buildings. The prt 

 vailing ores there are the black oxide of copper and the silicate c 

 copper; there &re no sulphurets of copper found in the whole r€ 

 gion. One valuable large vein contains, in the clear ore, 25 pe 

 cent of copper, besides silver; and the deeper they go the bette 

 it becomes. 



