Page:Quarterly Journal of the Geological Society of London, vol. 25.djvu/591

Rh a height at least 100 feet above the present stream, and afterwards altered its course, and flowed several miles to the north. But this could never have been the case: for, just as at Moulin Quignon and Saint Acheul the gravel-beds described by Mr. Prestwich are not commanded by any higher grounds, and are out of reach of all running water, and of any possible interference from agents in present action, so here they are found at an elevation of at least 80 feet above the source of the river, which is not more than twenty miles distant, and there is no high land in the neighbourhood from which a river capable of leaving such a deposit could possibly have been supplied. It is equally clear that if the water had been supplied, it never could have reached to the summit of the hills. These, as I have shown, immediately overlook or overhang the great level of the fens, which was formerly a considerable valley, much of it having been filled up by peat within a period comparatively recent. Before the river could have attained to a height sufficient to submerge the hills and cover them with its spoils, it must have fallen into the low grounds on either side, and, filling up the valley, have found its way to the sea, or, if not, it would have formed an inland lake; in either case the transporting power of the water would have been lost long before it reached the required level.

In confirmation of the views here stated, I may notice that flint-implement-bearing gravels have lately been observed in several other localities, on table-lands and hills far removed from any existing river, and destitute also of the slightest trace of any ancient river.

At the Reculvers they are obtained from a small patch of flint-gravel on a cliff overhanging the sea, and 80 feet above it; while at Hill Head, in Hampshire, and at Bournemouth, Dorset, they have been found in similar situations and at greater elevations.

A still more remarkable instance has been described by Mr. Bruce Foote as occurring near Madras. The implements here are made from pebbles of quartzite, and in form and workmanship are closely allied to the English and French types. They are found in a red ferruginous clay, known as laterite, which forms a belt eight or ten miles in width, running parallel with the coast-line for the distance of 300 miles. These beds are cut through at intervals, and to great depths, by the rivers of the country running at right angles to the coast-line, and falling into the Bay of Bengal. The implements are never found in the river-channels, except where it is clearly seen that they have been derived from the laterite cliffs. They occur at the height of 500, 1000, and even 1400 feet above the sea-level, and at this height are associated with enormously large boulder-gravels of quartzite capping the watersheds of the rivers. Like several French and English deposits, these beds rest upon the Cretaceous and Postcretaceous beds; like them they are entirely destitute of marine or freshwater fossils; and, like them also, they are frequently far distant from any river or river-channel.