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688 of a considerable elevation of the land from beneath the sea; and as the gravel in places overlies late Tertiary beds, this must have taken place at a comparatively late geological epoch. When rivers run through a tract of country covered with a marine gravel of this kind, itself apparently deposited in a somewhat contracted area, it is, in the absence of organic remains, difficult to distinguish the reconstructed gravels resulting from fluviatile action, from the older beds. Any one, however, who is acquainted with the country, or who will examine Mr. Codrington's map, will see what an enormous denudation has been effected in this great sheet of gravel, by rivers and streams, and by subäerial action. When once the protecting gravel has been cut through, and the soft Tertiary beds of sand and clay below have been reached, the process seems to go on with great rapidity, A large tract of land west of Southampton appears to have been in this way almost cleared of its gravel, of which but patches are left. Even the principal portion of the old table-land which has survived, that to the east and south-east of Fordingbridge, is deeply cut into by numerous valleys, many of a depth of 200 feet. The existence of these valleys is clearly in accordance with the river theory.

Let us now examine the discoveries in the valleys of the Test and of the Itchen from this point of view. Looking at the numerous instances of the finding of flint implements in gravels containing terrestrial and freshwater remains, and looking at the improbability of their occurring in a purely marine deposit, I venture to regard them as being equally characteristic of freshwater deposits as any organic fossils, and to claim the beds in which they occur as being of freshwater origin.

At Southampton several implements have been found in the pits upon the Common at heights ranging from 80 to 150 feet above the sea-level. The gravel there slopes at a considerably greater inclination than that of the table-land nearer Chilworth, with which it is continuous, and from which it would appear to have been in part derived. It occupies a tongue of land between the valley of the Itchen and that of the Test, now widened out by tidal action. It is in places covered by brick-earth, and its position and character are quite in accordance with a fluviatile origin. If, from their proximity to the apparently marine gravels, we assume these beds to belong to an early period in the history of the excavation of the valley, their high position above the present tidal stream is such as, according to the hypothesis, was to be expected.