BIRCH GROVES OF EPPING FOREST.
73
distribution. They were described by the late Sir Joseph Prest-
wich in 1890 as Westleton shingle, and more recently by a
late President, W. Whitaker. They are composed approximately
of:—
1. Flint pebbles 50%
2. White quartz pebbles 15%
3. Sub-angular fragments of flint 20%
4. Sub-angular fragments of chert 10%
5. Pebbles of Lydian stone and ragstone 5%4
There are few or no birches where there is a considerable
crater-like pocket in the clay filled with sandy gravel, for there
water stagnates, as (1) in part at least of Rushey Plain, 300
yards north of the King's Oak Hotel, (2) in the portion of ground
that is about 200 yards west of the Wake Arms, along the Waltham
Road, and south of the keeper's cottage, and (3) in part of the
Forest between the converging roads east and west of Great
Monk Wood. On one of these patches Sphagnum sp., Drosera
rotundifolia, Erica tetralix and Lycopodium inundatum were
until recently present, though not frequent.
The sand and gravel areas, when not in such hollows, are
well drained naturally, although considerable obstruction is
caused by luxuriant vegetation at the issue of springs and
for some distance below them. A scheme for draining such
swampy places was commenced in the late seventies of the
19th century. It consisted in digging deep straight ditches
through the boggy land, but owing to the strenuous efforts of
the Club, aided by the sympathetic help of influential Conserva-
tors, the artificial drainage was allowed to become obsolete and
no permanent lowering of the water-table of the plateau took
place. The water is known to have maintained an almost
constant level, six feet from the surface, for a long series of years
in wells near the 300 feet contour line.
There is an interesting paragraph in Water Supply of
Essex. "At the High Beach outlier, there are many springs
on the northern side of the Common, sometimes with a rich
growth of bog-moss (Sphagnum), and of other marsh plants.
On the east, in the nursery southward of the King's Oak Inn,
I saw, more lately, a spring with a bog garden." This delightful
miniature graphically illustrates one of the beauties that forest
4 Quart. Journ. Geol. Soc., 1890, pp. 84, 181.