LOW LEVEL GRAVELS OF THE RIVER LEA. 73
The breaking strain was therefore, .145 gramme. Addition
of the weight .070 gramme caused the thread to elongate half
an inch.
The length of the larva experimented with was 3/4 in. and its-
weight .063 gramme.
NOTES ON THE LOW-LEVEL GRAVELS OF
THE RIVER LEA AND THEIR PALAEOLITHIC
IMPLEMENTS,
By ARTHUR WRIGLEY.
[Read 27th February 1915.]
STUDENTS of palaeolithic man will be well aware that,
in respect of flint implements, the low-level gravels of
the Thames and its tributaries are singularly barren. The
occurrence even of derivative implements in the low-level gravels
of the Lea is therefore perhaps worth recording. From Wal-
thamstow to beyond Leyton and Stratford, the Lea meanders
through a wide, flat-bottomed valley, bounded on both the
Middlesex and Essex sides by a distinctly marked bank of middle
terrace deposits. On the Leyton side of the valley at Temple
Mills1 some excavations have yielded from the base of the
low-level gravel the well-known Arctic bed associated with
Pleistocene mammalia and derived palaeolithic implements.
The latter are of Chelles and St. Acheul types, greatly rolled,
having patinations very similar to those of the implements
found in the adjacent middle terrace deposits of Leyton and
Wanstead. Flint flakes have also been obtained; they have
no secondary chipping, and consequently are of no definite
type, but in general they present a late palaeolithic appearance.
One remarkable piece from this locality might well be a Solutrian
lance-head with the points broken off and greatly abraded, though
this, of course, is merely a conjecture. On the other side of
the Valley in the neighbourhood of Hackney Wick, the base
of the low level gravel has yielded a peat whose seeds suggest a
temperate flora with northern affinities, pleistocene mammalia,
and derived palaeolithic implements. These are of Chelles
type, much rolled, peat stained or with a sepia-coloured patina-
tion. As they occur in a bleached gravel, it is quite conceivable
1 Essex Nat., vol. xvii., p. 121.