In all probability the very oldest implements of the post-tertiary, and consequently the beginning of the glacial epoch, if not of the pliocene, are those found in the south of Hampshire, between Gosport and Southampton. They came from a tabular mass of drift which caps the tertiary strata. "The great bed of gravel resting on eocene tertiary strata, in which these implements have been found, consists in most places of half-rolled or semi-angular chalk flints, mixed with rounded pebbles washed out of the tertiary strata.... Many of them exhibit the same colors and ochreous stain as do the flints in the gravel in which they lay." West of the Southampton estuary, "on both sides of the opening at Bournemouth, flint tools of the ancient type have been met with in the gravel capping the cliffs. The gravel from which the flint tool was taken at Bournemouth is about one hundred feet above the level of the sea.... The gravel consists in great part of pebbles derived from tertiary strata." The oval flint implement discovered in gravel at the top of the Foreland cliff "is of the true palæolithic type, and the gravel in which it is imbedded at the height of about eighty feet above the level of the sea, may have once extended to the cliffs near Gosport; in which case we should have to infer that the channel called the Solent had not yet been scooped out when this region was inhabited by palæolithic man."[13] It may be safely inferred that the implements in the above three enumerations were imbedded at about the same time. The flint implements from the valley of the Somme, which have been of so much interest, and convinced so many sceptical geologists, belong to the early part of this epoch. This valley may be represented by Fig. 3. [Illustration: FIG. 3. SECTION ACROSS THE SOMME IN PICARDY. 1. Peat, twenty to thirty feet thick, resting on gravel, _a_. 2. Lower level gravel, with elephants' bones and flint tools covered with fluviatile loam, twenty to forty feet thick. 3. Upper level gravel, with similar fossils, and overlying loam. In all thirty feet thick. 4. Upland loam without shells, five or six feet thick. 5. Eocene tertiary strata, resting on the chalk in patches.] In explanation of the above it may be well to remark that No. 2 indicates the lower level gravels, and No. 3 the higher ones, which are from eighty to one hundred feet above the river. Of a later date than these is the peat, No. 1, which is from ten to thirty feet in thickness. Underneath the peat is a bed of gravel, _a_, from three to fourteen feet thick, resting on undisturbed chalk. But between the gravel and the peat is a thin layer of impervious clay. This section of the valley of the Somme is a pretty fair representation of the arrangements of the different beds at Abbeville, Amiens, and and St. Acheul.