A SKETCH OF THE GEOLOGY OF EPPING FOREST. 165
From Walthamstow, southward, the surface consists chiefly of
gravel of much later date and lower level than the Westleton Beds or
Glacial Gravel. It belongs to the present Valley Systems of the
Thames and Lea. It was deposited, however, by those streams when
they flowed at a higher level than they now do, and having more fall
brought down coarser material. It forms most of the surface of the
Forest district about Forest Gate, Wanstead, Leyton, Leytonstone,
and Walthamstow.
Then, lastly, we come to the lowest in level, and latest in date of
all the geological formations in, or bordering on, the Forest district,
the Alluvium of the Thames, Lea, and Roding; the most recent of the
deposits formed by those streams. In the "Trans. Essex Field Club,"
vol. iii., pp. 1 to 29 , will be found a valuable paper by Dr. Henry
Woodward on "The Ancient Fauna of Essex," giving a most inter-
esting account of the excavations made in the marshes of the Lea in
1868-69 by the East London Waterworks Company when constructing
additional reservoirs, and of the fossil remains found therein. At
the present time additional reservoirs are being made in the same
neighbourhood, and the sections exposed may be compared with
those given by Dr. Woodward. In both cases we find much variation
in detail, but an excavation 6 to 8 feet in depth, in 1895 as in 1868,
usually discloses clayey loam at the surface and gravel at the bottom,
with variable thicknesses of peat or shell-marl, or both, between the
loam and the gravel. Among the mammalian remains found in
1868-69, Dr. Woodward mentions those of the wolf, fox, beaver, horse,
wild boar, reindeer, gigantic ox (Bos primigenius), and elk. But
those wishing for a complete list must refer to Dr. Woodward's
paper.
References.—In addition to Mr. Whitaker's Memoir already men-
tioned, Sheet 120 of the Horizontal Sections of the Geological
Survey from the Chalk of Farningham, in Kent, to the outcrop of the
Chalk in the valley of the Ash, at Widford, will be found extremely
useful to the student of the geology of Western Essex.4
4 "120. From S.E. of Farningham, Kent, across the Valley of the Thames below Greenhithe ;
through Essex, to the Valley of the Ash at Widford. (1871). [Maps 1, N.W., S.W., 6, 47]." 5/-