Skeleton lately found at the Tilbury Docks, Essex. 141
little importance what name is given to an ancient geological
formation lying between two fairly definite horizons, great
care is necessary in dealing with the most modern, with
regard to which the evidence of relative antiquity is often
extremely scanty and doubtful. However, I do not object to
Pleistocene, here, on account of a preference for its equivalents,
"Newer-Pliocene" or "Post-Pliocene," but because the
Tilbury Dock Alluvium can only properly be classed as
"Recent." For, if the term Recent is ever applicable, it
must be to a series of strata the deposition of which began
when our Physical Geography was almost precisely what it
now is; and would be going on still, but for the embankment
which confines the river and prevents its overflow. The
writers of the newspaper paragraphs are also too much
inclined to dwell ou the depth at which the skeleton was
found as a proof that it is rightly described as Palaeolithic.
Of course the mere fact that it was discovered deep down in
alluvium that has received no addition to its thickness since
the Roman occupation proves the prehistoric age of the
skeleton. But human remains found at a depth of two or
three feet in an old alluvial deposit formed when the river
flowed at a height of twenty or thirty feet above its present
level (which would be styled Paleolithic by universal consent)
would have a claim to very much higher antiquity. They
would be also divided from remains found in recent alluvium
by a distinct interval of time, marked by a change in Physical
Geography. And I may here remind you that flint imple-
ments were discovered by M. Boucher De Perthes in old river-
gravel from 80 to 100 ft. above the present level of the River
Somme; and that they have also been found in old Thames
Valley deposits, 50 ft. above the present level of that stream.
Many examples might also be given of human remains found
in caves below a covering of stalagmite, and associated with
the bones of extinct Mammalia, which, again, would rightly
be styled Palaeolithic. It is necessary, however, to bear in
mind that the test of age in the latter case is by no means so
conclusive as that afforded by presence in strata of a certain
definite antiquity. For association with extinct Mammalia