86 PRIMAEVAL MAN IN THE VALLEY OF THE LEA.
flakes which had all evidently been struck from one block. From
this collection I was able to replace the two flakes shown in the
figure. Both flakes are sharp, clean, black, and lustrous, like the
majority of implements and flakes from "the Floor." This example
is in my own collection.
Flakes and Cores.
The simplest kind of knife-flake,
very common in the valley of the Lea,
is illustrated, one-half actual size, in
the example from Stoke Newington
Common, shown in fig. 5. By dexte-
rous and well-aimed flaking, a somewhat
large, thin, artificial splinter of flint,
with one edge as sharp as a knife, has
been struck from a flint block. Some-
times, when the flake has flown off with
an irregular edge, the irregularity has

Fig. 6.—Knife-flake, trimmed at one
edge and top (one-half actual size).
been remedied by fine secondary

chipping, as in the example at fig. 6,
engraved one-half actual size from a knife-form found by me on the
"Palaeolithic Floor" at Leyton, Essex. This example is now in
the British Museum, Bloomsbury.
Flakes, like the three specimens from Stoke Newington Common,
Fig. 7.—Flakes showing depressions in edge, caused by use (one-half actual size).
illustrated one-half actual size in fig. 7, are common in the gravels
of the Lea valley; they are interesting, as showing distinct marks of
use. In the positions where the dotted lines are shown, the edge of
the flake has been worn away by scraping bones, pieces of wood, or
other hard objects. Some examples are much better defined than