from a pit which I caused to be dug at Abbeville, in sand in contact with the chalk, and below certain fluvio-marine beds, which will be alluded to in the next chapter.
Fig. 14
Flint knife or flake from below the sand containing Cyrena fluminalis.
Menchecourt, Abbeville.
d Transverse section along the line of fracture, b, c.
Size, two-thirds of the original.
Between the spear-head and oval shapes, there are various intermediate gradations, and there are also a vast variety of very rude implements, many of which may have been rejected as failures, and others struck off as chips in the course of manufacturing the more perfect ones. Some of these chips can only be recognised by an experienced eye as bearing marks of human workmanship.
It has often been asked, how, without the use of metallic hammers, so many of these oval and spear-headed tools could have been wrought into so uniform a shape. Mr. Evans, in order experimentally to illustrate the process, constructed a stone hammer, by mounting a pebble in a wooden handle, and with this tool struck off flakes from the edge on both sides of a chalk flint, till it acquired precisely the same shape as the oval tool, fig. 9, p. 115.
If I were invited to estimate the probable number of the more perfect tools found in the valley of the Somme since 1842, rejecting all the knives, and all that might be suspected of being spurious or forged, I should conjecture that they far exceeded a thousand. Yet it would be a great mistake to imagine that an antiquary or geologist, who should devote a few weeks to the exploration of such a valley as that of the
