When examining this locality, I was struck with a significant fact, tending to show the long time that must have elapsed since the abandonment of these mines. I noticed in many instances that the artificial groove around the hammers was nearly obliterated upon the upper side, while upon the lower side, less exposed to the abrading agency of the atmosphere and rains, the groove presented a comparatively fresh appearance, and even the slight markings made by the tool that cut them were quite distinct. When I removed the overlying rock, and found a grooved maul in a protected spot, the groove was generally as fresh as though it had been made but a few months before. The compact nature of the stone of which these hammers are made, and their ability to resist the action of weather and moisture, prove conclusively that much time has been required to disintegrate their surface so as to obliterate the artificial work which has been expended upon them. I feel unwilling to leave this subject without instituting an inquiry relative to the time when these mines were wrought, and the people who worked them. Many who have been taught to regard the present roving tribes of Indians as instinctively wise in matters of medicine and mining are ready to award to that race the credit of having worked these mines; but, inasmuch as even a traditional knowledge of their existence was unknown to the Indians at the time the Jesuit missionaries visited that region in the sixteenth century, we incline to the opinion that an other and distinct race worked them. I am unable to see why the descendants of a people residing in the same country, and subject to the same wants, should abandon the half-worked mines which their ancestors had opened, and even fail to hand down to their posterity a tradition of their existence. If copper was in such demand that the ancestors of the present race of Chippeways were induced to work so perseveringly to obtain it, why did not the children continue to work, at least enough to finish the jobs already commenced by their progenitors? We cannot consistently attribute the Herculean labor expended on these mines to the ancestors of the indolent race of North American Indians. We incline, rather, to the opinion that the miners were the mound-builders, who resided south of the mines, and ultimately found a home in Mexico. The condition in which the mines were left favors this theory; for in many instances unfinished jobs are found,--as in the case of the mass of copper upon skids at the Minnesota Mine, and the half-severed veins in other mines. May we not reasonably suppose that the miners came from the South and worked during the summer months, returning to their homes in winter? The circumstance that no traces of their habitations or burial-places have ever been discovered in the immediate vicinity of the mines leads to the inference that they came from a distance; and the fact that copper rings, chisels, and knives, and occasionally stone