184 PRE-COLUMBIAN COPPER-MINING 



At tlie Miimesota mine, in Oiitouagoii County, was i'oand a large 

 piece of mass copper wliicli liad been raised some distance iu the exca- 

 vation and abandoned by the old Avorkeis, As this was the first large 

 mass discovered, and gave rise to considerable speculation, it deserves 

 special mention. The account is taken trom Forster and Whitney's 

 report on the geology of the Lake Superior cf)pper region, and is as 

 follows: In the winter of 1847-''48, Mr. Knapp, the agent of the Min- 

 nesota, found an artificial cavern on the mine location containing stone 

 hammers, and at the bottom was a vein with jagged i^rojections of 

 copper. After the snow had left in the s]»ring he found other excava- 

 tions, and particularly one 26 feet deep, filled \Yith clay and a matted 

 mass of moldering vegetable matter. On digging 18 feet he came to a 

 mass of native copper 10 feet long, 3 feet wide, ar.d nearly 2 feet thick, 

 'weighing over 6 tons. '' On digging around it the mass was found to 

 rest on billets of oak su])ported by sleepers of the same material. 

 This wood, by its long exposure to dampness, is dark-colored and has 

 lost all of its consistency. A knife blade may be thrust into it as 

 easily as into a peatbog. The earth was so packed around the copper 

 as to give it a firm support. The ancient miners had evidently raised 

 it about 5 feet and then abandoned the work as too laborious. They 

 had taken off every projecting point which was accessible, so that the 

 exposed surface was smooth. Below this the vein was subsequently 

 found filled with a sheet of copj>er 5 feet thick and of an undetermined 

 extent vertically and longitudinally. - - - The vein Avas wrought 

 in the form of an open trench, and where the copper was most abundant, 



intendent iu laying water pipes opened a Aery old grave. The grave was in the 

 yellow sand, in a grove of Norway pines, near Lake Sa])erior. At the bottom there 

 was an exceedingly thin layer of mold, darker than the sand. Some human teeth 

 were found and a string of copper Iteads strung on sinews. The sinews, much 

 decayed, still held the heads iu place. The copper bead was a small thin j)iece of 

 copper about one-fourth of an inch long. It was riidely bent into a cylinder for the 

 string to pass through, but was not welded; the edges were iu contact, but not 

 fastened together. This grave was at the Grand Portage or carrying place. 



"In dredging, the dipper brought up from the bed of the ship canal where the 

 sand drift had originally been at least 25 feet deep, several perfect stone hammers 

 and a copper implement which I pronouuced to have been the head and ferule of a 

 pike pole. It was about 18 inches long, taperiug, sharp, and solid for two-thii'ds the 

 distnnce from the small or lower end. At the upper or pole end the copper had been 

 flattened out and then bent round to form a socket for the pole. There Avas a slight 

 o]»ening betAveen the two edges of the curved copper; it Avas not joined or av elded. 

 Tlie pike Avas bright and shiniug like a clean copper kettle. 



"I sa,Av it, and it was dredged from the bottom of the canal, and its position, as 

 regards strata, Avas under the drift or dune sand and ou the hard graA^el and clay 

 underlying. I know of no other tinds in that section. The gravel and hard pan 

 fouud in the bottom of the dredged canal I regarded as the bed of the ancient 

 stream or estuary, now filled up with drift sand blown in from Lake Superior. 

 How much the glacial drift had to do in filling up the ancient gorge in which the 

 present canal is only a line, I can not say. In some of the marshes cut by the canal 

 were fouud three distinct forests, one growing on top of the other, to a depth of 14 

 feet." 



