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"ON THE PLEISTOCENE DEPOSITS OF THE
ILFORD AND WANSTEAD DISTRICT, ESSEX."
IN 1899 I read a paper, before the Geologists' Association of
London,1 on the Ilford and Wanstead district. Since the
reading of that paper, some further sections of the Pleistocene
deposits have been exposed at those places and since they are of
some interest they form part of the subject of the present paper.
In the paper above mentioned, I dealt with the subject under
two headings, viz., (1) High Terrace Drift and (2) Lower or
Middle Terrace Drift.
A description of the large patch of High Terrace Drift which
occurs at Wanstead was given ; this description included details
of a remarkable section of contorted gravels which was exposed
early in 1898 at a pit to the north-west of Wanstead Park. The
importance of this section is obvious when it is mentioned that
the contorted drift was capped with genuine, in situ Pleistocene
gravel, which thus proved the antiquity of the disturbance. I
ascribed the disturbances to the grounding of river ice.
Mention was made of the occurrence of Equus caballus in
the gravel here. The occurrence of seams of Manganese was also
noted and in connection with this I made many observations in
the Wanstead pit on the origin of the seams. My conclusions
were published in a paper in Science Gossip,2 in which it was
contended that the Manganese seams did not owe their origin to
filtration from the surface, but to fluviatile deposition contem-
poraneous with the deposition of the gravels.
Further sections of the gravel in this pit have afforded me
many examples of contortion. Sometimes the seams of sand
and gravel are so twisted up as to resemble loose knots.
One section is worthy of being given in detail here. The
beds seen were as follows :—
(1) Surface soil and made earth ... 2ft.
(2) Gravel, with lenticular patches
of sand, one of which had its
top and bottom layers
cemented into 'iron-pan' ... 4ft.
1 Martin A. C. Hinton.— "The Pleistocene Deposits of the Ilford and Wanstead
District," Proc. Geol. Assoc. Vol. xvi., part for Feb. 1900.
2 Martin A. C, Hinton.—"Manganese in River Gravels," Science Gossip, vol. vi., N.S.
pp. 146-147