greenstone and other rocks not purely silicious, some scraping as well as grinding tools may have been employed, and possibly the wear of the edge of some of these tools may be due to such a cause. Even among the cave-dwellers of the Dordogne we find scrapers bearing similar marks of attrition, and we also know that flint flakes were used for scraping the hard hæmatitic iron ore, to produce the red pigment—the paint with which the men of those times seem to have adorned themselves.[1414] It will of course be urged that it is, after all, only a small proportion of these implements which bear these unmistakeable marks of wear upon them. It must, however, be remembered, that to produce much abrasion of the edge of an instrument made of so hard a material as flint, an enormous amount of wear against so soft a substance as hide would be necessary. It is indeed possible that the edge would remain for years comparatively unworn were the substance to be scraped perfectly free from grit and dirt. If we find identically the same forms of instruments, both worn and unworn, there is a fair presumption that both were intended for the same purpose, though the one, from accidental causes, has escaped the wear and tear visible on the other. There are, however, circumstances which in this case point to an almost similar form having served two totally distinct purposes; for besides those showing the marks of use already described, we find some of these instruments with the edge battered and bruised to such an extent that it can hardly have been the result of scraping in the ordinary sense of the word.