1866..
FISHEK WAEP.
557
so up the hill. The drifted fragment is much distorted, but never-
theless not scattered. There are similar patches of this bed in the
trail in an old Crag-pit on the Saxmundham road, about a mile and a
half from Aldborough.
A similar case was seen by Mr. Boyd Dawkins and myself at
Walton-on-the-Naze, where an angular lump of London Clay, about
eighteen inches in diameter, was entirely enveloped in a mass of
gravelly trail.
Fig. 5. — Section across a furrow of Trail covered hy Warp, left
standing after the removal of the surrounding gravel for ballast,
Wivenhoe, Essex.
a. Warp.
b. Trail.
The position of the pebbles in the trail, and still more so the con-
torted but unscattered condition of incoherent material, show that
the trail has been transported in a plastic state (as mud) moving by
its own gravity, or else pressed onwards by some other agent.
Fig. 6. — Section of Trail near Villa Farm, Tendring Hundred
Railway.
.:vj.-.v ..■.;.-.:_; -.:?^ a. Warp.

V«/;^'?,.-

V:':'?:?:^;'f^.- b. Trail of sandy gravel.

r^-.0;'i..-.'-V;-.v,\-v.

;T;-:3; .?• London clay,

d. Weathered surface of
London clay, full of
Slickensides.
I can cite instances which prove that considerable force has been
involved in this process. In a railway- cutting near Wivenhoe,
in Essex, I found at the side of a valley one of these farrows in
London clay, about 13 feet deep, filled with such sand and gravel as
caps the tableland around. The clay, for the thickness of 4 or 5
inches, was kneaded into a plastic state, laminated, and full through-
out of polished surfaces of slickensides, showing that the trail which