Page:Popular Science Monthly Volume 19.djvu/623

 made by an unskilled hand, and was unfinished. This allies these miners with those of the south shore of the lake. The absence of these hard, rounded stones on the shores of the south side of Lake Superior, owing to the strike of the formation producing them across the interior of the States of Michigan and Wisconsin, made it necessary for the miners on that side to manufacture their hammers, which they did with greater perfection and symmetry than are seen in the beach-wrought hammers of the Isle Royale miners; and they almost invariably grooved them for a withe. Those found on Isle Royale are generally broken with use on one end or on both, a fact which probably caused their abandonment. Fig. 5 shows the imperfectly grooved



hammer belonging to Dr. Gailey. Fig. 6 shows the outline and irregularity of three others, also found at the Minong mine. These are a fair average for form, of the most of those found. They are also evidently such as would result from the constant attrition of angular fragments on the beach, and show no evidence of designed shaping.



Their battered and even fractured extremities are the only sign of the agency of man in giving them shape.

If we inquire now who were the men, and when did they live, who did this work, we enter on a very interesting question, but one on which we are not in total darkness. A single observation at the pits at once places them later than the last glacial epoch. The dirt that