Forbidden Archeology_ The Full Unabridged Edition - Michael A. Cremo [182]
To these objections Verworn replied as follows. First of all, in no case were fossils of mammals that lived only in the Pleistocene found together with flint implements beneath the lava at Aurillac. This indicated that there had been no Quaternary eruptions. Therefore, any flint-bearing beds found under the several layers of lava were definitely Pliocene or older. Furthermore, the layers of basalt and other volcanic rock were separated by freshwater sedimentary beds with sharply characteristic fossil remains. For example, one might find under a particular layer of basalt a sedimentary bed containing Pliocene fossils and under this another layer of basalt. Under this second bed of basalt, one might then find another sedimentary layer, this with fossil remains of Miocene plants and animals along with flint implements. And under a third layer of basalt one might find another Miocene sedimentary layer containing flint implements, this layer lying upon the Oligocene basement formation. From such evidence, Verworn concluded that the flint-bearing sedimentary beds below or directly above the lowest layer of basalt at Aurillac were Miocene rather than Pliocene in age.
Verworn (1905, p. 20) concluded: “So we find these implement-bearing layers always directly over the Oligocene or directly upon the basalt from the oldest eruptions, which directly cover the Oligocene layers. The fact that over these oldest eruptive masses one finds beds that contain a typical Late Miocene fauna, like that found at Joursac, with Hipparion, Dinotherium, etc., means that the underlying implement-bearing beds cannot be any more recent than the Late Miocene. Thus the second doubt of Keilhack, namely that the Miocene fauna has been secondarily introduced into the implement-bearing layers from below, is cleared away.”
Verworn (1905, p. 21) then discussed at length various ways to identify human work on a flint object. He divided evidence of such work into two groups: (1) signs of percussion resulting from the primary blow that detached the flake from a flint core; (2) signs of percussion resulting from secondary edge-chipping on the flake itself.
On a flint flake, the principal signs of percussion from the main blow that detached the flake from a flint core would be a striking platform, bulb of percussion, and eraillure. According to de Mortillet, the presence of a striking platform, bulb of percussion, and eraillure together on a flake is a very good indicator of intentional work (Verworn 1905, pp. 21–22).
In addition to the three features mentioned above, Verworn (1905, pp. 22–23) described several more signs of percussion that can be observed on flint flakes (Figure 4.15). Concentrated near the point of impact on the top of the flake one can see a small formation of concentric circular cracks. Radiating from the point of impact and extending over the entire surface of the flake there is also visible a series of curved percussion marks, or force ripples. The stronger the blow that separated the flake from the flint core, the stronger the ripples. Raylike cracks, emanating from the point of impact, intersect the curved force ripples. Verworn also pointed out that in a flake made by percussion the plane of fracture is not straight. If one looks at the flake, edge on from the side, one sees that the ventral surface of the flake is convex at the bulb of percussion, near the top of the flake, and concave at the lower portion, giving an S-shaped contour. Sometimes one can also see on the striking platform a crush mark from a previous blow that failed to detach the flake from the flint core. Negative impressions of some of the above-mentioned features are sometimes visible on the