The second argument for the dawn stone was impressive. In 1910, after years of search, J. Reid Moir found eoliths near Ipswich, England, under unusual conditions. They came in two layers, which seemed to indicate that early man had camped twice in this neighborhood at different times. They were bedded in soft sand and therefore could not have been chipped by geologic pressure. The sand dated from the Pliocene Period which preceded the Great Ice Age. Later, in the same district, he found eoliths in a layer of delicate shells—again a sign that the eoliths had not been chipped by natural forces.[6] Moreover, many of Moir’s eoliths had a new and peculiar shape; they were keeled like an upturned boat or beaked like an eagle. Sir Ray Lankester called them rostrocarinates. In 1900 Mortillet had to admit man—or pre-man—to an Eolithic Age. Flake vs. Core Industries More difficulties beset Mortillet and his system of names and cultures as time passed and as fellow scientists dug new caves and terraces, and turned up stone tools of other patterns and other periods. Implements appeared that did not fit into the Frenchman’s classic system. A supplementary scheme had to be devised, and soon it, too, failed to fit the facts. The new system divided all paleolithic tools into two types—which was sound enough—and assigned each type to certain peoples and to those peoples only—which proved not so sound. The division lay between cores and flakes. It lay between tools that had been made out of the heart of a lump of flint, and tools that had been made from chips flaked off the lump. The fact that there were core tools and flake tools was plain enough, but the fondness of scientists for strict classification led the prehistorians into theories that time disproved. First of all, they had to set up a time sequence. They decided, not unnaturally, that man must have begun by hammering things with a handy rock until his rude tool began to chip away into something approaching an edge and eventually a point. Thus the hand ax, or _coup de poing_, came into being (see illustration, page 71). In the course of time man began to notice the chips, and to use the larger ones to cut and scrape with. Soon—that is, after a couple of hundred thousand years—he was deliberately knocking flakes off a stone core, and using them for spear points as well as scrapers. The prehistorians called hand axes the products of a “core industry,” and chips the products of a “flake industry.” They believed that one industry had preceded the other by hundreds of thousands of years, and that the Abbevillian and Acheulean had stuck to cores and left flakes to the Mousterian. Thus they believed that certain cultures had devoted themselves exclusively to the core, and certain others to the flake.