IN NOKTH AMERICA. 1^5 



there the excavatious extended deepest. The trench is j,'enera]ly tilled 

 to within a foot of the snrlaoe with the wash from the surrounding 

 surface, interiningied with leaves nearly decayed.'' Whittlesey says 

 of this mass: '^ Its upper surface and edges were beaten and pounded 

 smooth, all the irregularities taken off, and around the outside a rim 

 or lip was formed, bending downwards, - - - Such copper as could 

 be sei)arated by their tools was thus broken off; the beaten surface 

 was smooth and i^olished. 



''On the edge of the excavation in which the mass was found there 

 stood an ancient heiidock, the roots of which extended across the ditch, 

 1 counted the rings of annual growth on its stump and found them to 

 be 290." Mr. Knapp felled another tree growing in a similar position, 

 wiiich had 395 rings. "The fallen and decayed trunks of trees of a 

 l)revious generation were seen lying across the i»its.'' A shaft was 

 subsequently sunk on the lode revealed by this trench, which aa as iu 

 rich ground, to a great depth. The abandonment of this mass of cop- 

 ])er formerly gave rise to conjectures. It Avas supposed that the ancient 

 miners were interrupted in their work "by some terrible pestilence 

 - - - or by the breaking out of war; or, as seems not less probable, 

 by the invasion of the mineral region by a barbarian race, ignorant of 

 all the arts of the ancient Mound-builders of the Mississippi and of 

 Lake Superior.^'* But from a consideration of tlie evidence of the 

 character and scope of the old workings which we now possess it will 

 be seen that it is unnecessary to go so far for an explanation. As was 

 clearly the case at the Central and Mesnard mines and on Isle lioyale, 

 the mass at the Minnesota was abandoned by the old miners because 

 they found it im])ossible to get any more ])ieces from it. They had no 

 tools which could cut it, and even at the present time mass copi)er is 

 the least desirable form in which the metal i^resents itself in the mines, 

 on account of the labor and expense of cutting it n\), although there 

 are steel tools especially invented for the purpose. The practice of 

 hammering oif pieces from mass copper is mentioned by visitors to the 

 lake from the French missionaries down to Schoolcraft. There was a 

 large mass on the Ontonagon, which has been in the Smithsonian Insti- 

 tution for many years, which was considerably reduced iu size in this 

 way in the course of a hundred and fifty years by casual visits, 



A great antiquity has been assigned to these workings by some 

 writers, and it used to be supposed that a, Imsy industry was suddenly 

 interru])ted in them at some time over five hundred years ago. The 

 tiee with three hundred and ninety-five rings of growth has been used 

 to support an argument that the Avorkings must have been abandoned 

 at least as long ago as the middle of the fifteenth (century, or, to be 

 exact, reckoning from 1847, before the year 14r)2, This A\M)uld be at 

 least forty years before the voyage of Columbus and eighty-four years 

 before Cartier visited Montreal. Although it may be true that Avork 

 * Wilson ; I'rehialoric Man, \o\. i, p. 278, 



