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resemble those of the Indians in other parts of the country, con- 

 sisting of oval pieces of stone flattened on the sides, with a 

 transverse groove for the attachment of a handle ; some of them 

 weighed forty pounds. From the quantity of charcoal found in 

 these old workings, it is probable that the mining process em- 

 ployed was that used by nations of antiquity, namely, that of heat- 

 ing the rock enclosing the metal, by building fires about it, and 

 dashing on water when heated, causing it to split by the sudden 

 contraction. Near the Minesota location is a mound, probably 

 artificial, fifteen feet square, similar in appearance to the Ohio 

 mounds. It is a reasonable supposition, that^ it was built by the 

 same race, and that they were also the workers in the neigh- 

 boring copper mines. 



Mr. Foster stated, that in the Ohio mounds mica is found six 

 hundred miles from the source from which it must have come, 

 and rings of copper which must have been brought from Lake 

 Superior ; also stone hammers similar to those found at the 

 workings. Mr. Whitney remarked that analysis of the copper 

 would show at once whether it came from this locality, but he 

 had not yet been able to procure a specimen for this purpose. 



Mr. Whitney also gave an account of the immense deposits 

 of iron ore near Lake Superior. It exists in the form mostly of 

 fine-grained, almost chemically pure peroxyd. It occupies 

 about eighty quarter sections of the mineral country, and at the 

 nearest point is about twelve miles from the Lake. The quan- 

 tity of the ore is beyond calculation, and the iron made from it 

 is equal to the best Swedish. It appears in the form of solid 

 ridges and knobs, evidently of igneous origin, the highest being 

 about eleven hundred feet above the level of the Lake, and some 

 of them being half a mile long. The cost of the iron when 

 manufactured is from twenty-four to thirty dollars ; the price of 

 Swedish is about ninety dollars. The forest in the vicinity of 

 the ore aflfords abundant materials for charcoal for smelting 

 purposes. 



Mr. Whitney exhibited to the Society a specimen of banded 

 jasper and peroxyd of iron from a knob eleven hundred feet 

 above Lake Superior, presenting a beautifully contrasted appear- 

 ance. The whole mass was similarly constituted. It has been 

 suggested that it might be useful for ornamental purposes. He 



