The Quarterly journal of the Geological Society of London . , vol. viii, p. 143. Quart. Journ. Geol. Soc. vol. xlvi, p. 562. Vol. 54.] OF THE DISTRICT. 185 Since I wrote the above-meutioned paper, I have examined thestones on various modern beaches, and have noticed that stones ofwhatever shape soon become rolled to pebbles on a sea-beach. Imay mention the beach of Pecamp in JN^ormandy. The clitis thereare lofty, they are composed of Chalk with a great deal of flint,and yet angular flints are quite rare on the beach. Now, the gravelsof the district with which I am dealing are largely
The Quarterly journal of the Geological Society of London . , vol. viii, p. 143. Quart. Journ. Geol. Soc. vol. xlvi, p. 562. Vol. 54.] OF THE DISTRICT. 185 Since I wrote the above-meutioned paper, I have examined thestones on various modern beaches, and have noticed that stones ofwhatever shape soon become rolled to pebbles on a sea-beach. Imay mention the beach of Pecamp in JN^ormandy. The clitis thereare lofty, they are composed of Chalk with a great deal of flint,and yet angular flints are quite rare on the beach. Now, the gravelsof the district with which I am dealing are largely composed offlints, Avhich, though they show signs of the action of water, arefar more angular and irregular in shape than those of the sea-beaches which I have examined. Some of the flints, indeed,show so little sign of wear that I am tempted to doubt whetherthey could have been transported to their present position withoutthe aid of ice. Fig. 1.—Easthampstead Plain, Gravel Hill: sai^sen with rootlet-tubes; large Jiints very little rolled or [Level: 400 feet above Ordnance datum.] Large nnwaterworn or very little water worn flints occur inthe gravel at Shoppenhangers Farm, Maidenhead, 110 feet aboveOrdnance datum ; at the Hockett, Cookham Dene, 351 feet aboveOrdnance datum ; at Caversham, and other localities. But there isChalk at the present surface of the ground in close proximity tothese places, and the flints may have travelled only a short distance. This cannot be said, however, of the flints found in the gravelof Easthampstead Plain, 400 feet above Ordnance datum ; and I havea photograph (fig. 1) showing six large flints which have certainly 186 ME. H. W. MOXCKTOiSr ON SOME GRAVELS [MaV 1898, not been much rolled or waterworn. These I found in a pit atGravel Hill, one of the northern spurs of the plateau of the East-hampstead Plain, and ^ mile east of the Easthampstead CaesarsCamp. The two large blocks in the photograph (tig. 1, p. 185) aresarsens. I have s
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