134 ON SOME PLATEAU DEPOSITS AT FELSTEAD AND STEBBING.
take Glacial Gravel for Boulder Clay derivatives.3 The members of
one are enclosed in a matrix of sand or sandy loam, and in the other
of clay or chalky clay. In one the stones are much water-worn and
abraded, and in the other the flints are often entire or sharply-
splintered, and seldom show any signs of water-wearing. Pieces of
Oolitic rock, with fossils, are frequent in the Boulder Clay, but never
occur in the Glacial Gravels hereabouts. Precisely the same may
be said of the Post-Glacial Gravels under consideration.
When we consider the position of this gravel, occupying practi-
cally the highest land within nearly a mile radius, and remember that
it belongs to the closing scenes of the glacial disturbance, we shall
have a better apprehension of the work of denudation which has
since been in progress, and of the great changes in contour which
have occurred. This single instance, in fact, demonstrates the exist-
ence of Plateau Gravels which are now reduced to a remnant.
At Blewitt's Pit, Stebbing, about a mile N.N.E, of the church
(old one-inch map, sheet 47), there is a deposit of very sandy loam,
with large boulders, overlying Westleton Gravel, which is only to be
accounted for on the supposition that this friable loam is the repre-
sentative of a deposit now almost vanished. The loam is much
too sandy and friable to be mistaken for weathered Boulder Clay.
At any rate, I have not seen any weathered Boulder Clay at all like
this deposit.4 It has a faint tinge of purple, and were it not for the
large boulders entombed, I should say it was a rain-wash derived
from the Westleton Gravel. The loam occupies a considerable
elevation, say sixty to seventy feet above the Stebbing Brook, but
it is surrounded on three sides by rather higher land. These higher
eminences now consist of Westleton Gravel or Boulder Clay.
There are other sandy loams in the vicinities of Willows Green,
Fairwood Common, and Rayne, which appear to stand on the
same footing as that at Stebbing ; but we cannot in these cases
separate so clearly the influence of surrounding beds.
These Plateau Gravels (in the sense that they overlie Boulder
Clay) have been called Post-Glacial; but they have no other claim
to that epithet, as evidence exists of arctic conditions obtaining
posterior to the format on of those gravels. This is to be found
3 "But there are sometimes beds of Boulder Clay in this Gravel—'not in the tract described
perhaps—and also there are beds of Gravel in Boulder Clay.''—W. Whitaker.
4 "In Suffolk I have seen, in section, Boulder Clay passing laterally into sandy stony loam
(see Southwold Memoir). Some Boulder Clay is very sandy."—W. Whitaker.