Page:Quarterly Journal of the Geological Society of London, vol. 25.djvu/582

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PROCEEDINGS OF THE GEOLOGICAL SOCIETY.

deposit is met with, the position of which, however, is essentially different from that found at Broomhill. From a careful survey which

Plan of Gravel Hill, Brandon.

+ Gravel-pits.—Height 90⋅62 feet, from A to B, taken from the level of the river. Distance from the river 78 chains.

I have lately made it is found to be 91 feet above the river, and very nearly a mile distant from it at the nearest point; it comprises an area of from thirty to forty acres, occupying the summit of a hill overlooking an extensive sandy plain, which at a short distance merges in the great level of the fens. The bed of gravel here is usually not more than 10 feet in thickness, and often less, resting immediately upon the chalk; and, as at Broomhill, the implements are usually found at the bottom of it, and occasionally they lie upon the chalk. As regards its composition, however, no less than its position, this gravel differs greatly from that found at Brandon; the nodules of flint are not so large, there is very little of the broken chalk, and the mass of the overlying sand is much less.

By far the larger proportion (perhaps three-fourths of the whole mass of gravel) consists of rounded quartzites, and a few jasper-pebbles, while at Broomhill the proportion of these is hardly a thirtieth part of the whole. In some spots, indeed, these pebbles form a compact mass with hardly a single flint; and under one of these, at a depth of 6 feet, I procured a very well-shaped implement. The implements here are not generally stained of so deep a colour as those at Broomhill; and while many of them are of very coarse workmanship, and much worn and broken, others are of excellent forms, and as sharp and fresh as when first made.

Lakenheath.—The next deposit which I have examined is at Lakenheath, Suffolk, distant three miles from the left bank of the river. It is found on some high ground known as the Broom, between Lakenheath and Eriswell, and is at about the same height above the river, and of the same character as that at Gravel Hill, from which it is separated only by a shallow valley. These hills are only two miles and a half apart, and the beds which now cap them were