PALEOLITHIC INDUSTRIES, CLACTON AND DOVERCOURT. 5
Between this Boyn Hill (or 100-foot terrace) and the Taplow
(or 50-foot terrace) there is an intermediate sheet of gravel, the
Furze Platt gravel, not separately distinguished on the Geological
Survey maps, although the difference in palaeolithic industry
is of great importance. The outstanding Palaeoliths of this stage
may well be called the Grays Inn Lane series, after the celebrated
example found in A.D. 1690.
This "Grays Inn" group includes some ovate and other types,
and also some trimmed flakes and scrapers, but the predominant
form is the familiar "River-drift" pointed implement.
The same story is repeated in the Lower Thames. The
Dartford Heath gravel (the true Boyn Hill stage) yields the
earlier Palaeoliths, while the middle gravel of Milton Street yields
the Grays Inn group. Although there is not much difference in
level between the two deposits there is the same difference in the
flint industries that is observed in the Maidenhead district.
Immediately overlying the gravels containing the Grays Inn
group there is a notable change in technique, the pointed imple-
ment giving place to the twisted-ovate as the outstanding type.
The Grays Inn group is found not only, as at Maidenhead,
in a gravel that comes between the Boyn Hill and Taplow
terraces, but it is also distinctively characteristic of the older
river-bed gravels that underlie the higher parts of the 50-foot
or Taplow terrace.
In my opinion it is the realization of what I call the Furze
Platt stage with its Grays Inn Lane industry (although this
does not occur at a uniform level) that is the key to the better
understanding of the river deposits of the Thames, which, as
we have seen, should be the basis of comparison with those of
Eastern Essex.
Fig. 12 1 (see also 2, 1, 2, 2) is an ideal representation of the
"Oldest Class" characteristic of the Boyn Hill gravels. These
implements are usually rather small, thick and clumsy and
crudely flaked ; some are pointed, but the majority approximate
to a rude ovate in outline. This "Oldest Class" corresponds
with the French Strepyan as understood in the 1915 edition of
Sollas's Ancient Hunters. It was formerly more usually known
as the "Pre-Chellian" ; but this group is now the "Chellian,"
as understood for the time being in France.
2 Fig. 1 is reproduced, by permission, from the Trans. S.E. Union Scient. Soc., 1926.