48 PALAEOLITHIC AND NEOLITHIC IMPLEMENTS.
turbed sections, but the mineral condition of the implements
from the two beds is so uniformly and markedly distinct that
there is never any difficulty in separating them. This is so far
satisfactory, but on the other hand I do not know of any one
spot where both series can be found together in anything like
equal abundance. After prolonged search I have, however,
succeeded in finding several examples of the presumed earlier
series in situ in the brown clay (Number 4) directly underneath
the Buried Prehistoric surface. Taking into account the obvious
differences in type between the two series (to which I will next
refer), I think this is a very strong confirmation of the theory of
their difference in age.
Both of these series yield polished stone implements, and we
should ordinarily call them both alike Neolithic. Some of the
pottery from bed No. 5 is, however, rather suggestive of the
Bronze Age, and I am inclined to think that an early part of
the Bronze Age is the most probable date of the later series.
This pottery I found near a hearth, in the Buried Prehistoric
Surface; the hearth was about three feet in diameter and about
one foot or rather more in depth, and was nearly filled with wood
charcoal. I dug this material entirely out without finding
anything of interest. The clay round its margin was considerably
burnt. Some distance from this I also noticed the remains of
some piles and fascine structures, but not enough of these could
be seen to make out any definite plan or purpose in their
construction. These were on the level of the Buried Prehistoric
Surface, and apparently beneath the Scrobicularia-clay, but
Scrobiculana-clay may be of any age, and it is possible that the
piles may be later than their position would seem to suggest.
It is not easy to describe the differences in the technique of
the two series of implements. It is almost equally difficult to
illustrate it without figuring a long series of implements, for
these differences do not come out so much in striking
peculiarities in individual specimens, as in constantly recurring
tendencies towards the production of certain forms. One point
that is especially worthy of note is that leaf-shaped and barbed
arrow-points of advanced types are characteristic of the
presumed later series of implements, while the arrow-points of
the series that I take upon Stratigraphical grounds to be the earlier
of the two are generally of a more primitive character. Other