The writer discovered this granite in 1915, at which time various hypotheses were considered to account for its occurrence. As the rock lies over the prairie in scattered blocks, is extremely coarse grained, in all cases examined was found to rest on shales, and the wells, which at that time had been drilled just beyond the eastern margin of the distribution, were reported to have penetrated rocks of the normal sequence of the region, it was found difficult to relate the granite blocks to an intrusive. The results of the field and laboratory studies were published, together with all hypotheses considered, the hypothesis of the blocks having been brought to their present position by ice-action being favored.2 Subsequently a well was drilled about a quarter of a mile south of the place of greatest abundance of granite blocks. The samples were not kept, but the driller’s log showed the . . .