EXTRACTS FOREIGN AND DOMESTIC. 161 



Prof. Dewey suggested that if that was the case universally, 

 he best plan for speculation would be to buy wider somebody. 

 Much laughter.) 



Dr. .Jackson warned people, however, against being too san- 

 :,uii)c; there would be a good many poor mines opened there; and 

 s many bad speculations as there were in the Maine timber lands. 

 Laughter.) The copper veins are easily found; they run south 

 !5 degrees west, and wherever we find a ravine with the depres- 

 ion conformable to that line we are sure to find a vein of copper; 

 ■r a wet place in a ravine where the plants grow luxuriantly, it is a 

 )roof that the vein decays faster than the enclosing rock, and that 

 ein is copper. The best flux necessary to reduce copper ore is 

 lie calcareous spar, and that is found in great abundance there. 

 'lie great question is, "Will these copper veins hold ouf?" In 

 lie West India copper mines the native copper changes tosulphu- 

 ets as we penetrate the mine. The laws of gravity are in fa- 

 or of the fact that the deeper we go the richer will be the vein, 

 low shall we go down in the earth until we come to that spot 

 here we can ladle out the melted copper? I forget how far Pre- 

 ssor Rogers said that would be. 



Prof. Rogers. — About ten miles ! (Laughter.) 



Dr. Jackson. — We have abundant proofs in our specimens that 

 le copper and silver must have melted together; we find silver in 

 le copper, but we never find a trace of the copper in the silver, 

 ^'e find also zigzag veins of silver running through the copper. 

 low if we try to make an amalgam of these metals, if we melt the 

 jpperand bring the silver to a contact with it, part of the silver 

 ill unite with the copper and the rest remain pure silver in me- 

 iianical contact with it; but if we melt the silver and bring the 

 ppper in contact with it they will thoroughly amalgamate. And 

 lis singular segregation we find done by nature in the copper veins 

 f the Lake Superior region. The plan proposed for separating 

 le copper and silver in these ores, is to make all the copper into 

 lue vitriol, then make the silver into a chloride of silver, reduce 

 , and send it to the mint. The copper ore will be broken up at 

 lemine, carefully washed and picked, and then packed up in kegs 

 id sent down to Boston to be smelted. There is also an ore of 

 itimonial silver found in these mines. The sandstone of this re- 

 lon has no copper in it; but at the point of contact with the trap 

 bcks, there is a little native copper. The rich vein of black ox- 



e of copper opened at Fort \Vilkinsis 14 feet thick, and contains 

 J per cent of copper. In a ton of the rude ore, as delivered by 

 le miner at the pit bank on Eagle river, there is the following 

 jr centage : — 



Of Silver i $87 25 



Of Copper 42 10 



Total $129 35 



VOL. 11. — NO. I. V 



