Section of Clay with Flints near Woldingham. 13 
prevent the sand from sinking to any depth down the centre of 
the pipe, since the underlying clay would naturally fill up any 
narrow depression. 
I think these narrow pipes with sand in the centre of the 
pipe, with considerable depth of surrounding clay, go to prove 
that the clay was not of great thickness when the pipe began to 
form, but that there must have been some clay before the sand 
began to sink, and that the clay has gone on thickening ever 
since, so that now there is a great thickness of clay surrounding 
and overwhelming the sand. 
The very large quantity of Flints, all unbroken and unrolled, 
contained in the Clay of this section supports the theory that the 
latter is the insoluble portion of the Chalk; in no other way does 
it seem possible that such large unrolled Flints could be pre- 
served. We are not accustomed to seeing in our gravels or 
elsewhere Flints of their natural size—even in Chalk-pits they 
are usually broken as they are uncovered, and only disclosed a 
few at a time; but in a section like the one under consideration 
we see them of full size, and freed from their original matrix. 
It is unfortunate that this excavation was not made on a spot 
where there is undoubted Southern Drift, as such a section, at a 
spot where that drift was exposed upon the surface at an elevation 
of 860 ft., might have been very useful in elucidating some of 
the problems connected with that gravel and its accompanying 
eolithic implements. 
At all events such a section shows the desirability of more 
closely defining and mapping the different deposits comprised 
under the term ‘Clay with Flints.” Clay containing unrolled 
Flints, free from an admixture of other rocks, formed, as far as 
we know, by thé dissolution of the Chalk, might be always specified 
as ‘‘ Red Clay with Flints” ; and when other rocks than unrolled 
Flints are associated with Clay, the formation should be termed 
“Clay with Southern Drift,” or whatever other term may best 
describe the formation, according to its specific character. 
I particularly think this is necessary for the purpose of de- 
fining the implement-bearing Clays, for I note that Prestwich, 
in ‘Primitive Characters of the Flint Implements of the Chalk 
Plateau of Kent,’ refers to Mr. Harrison having found eoliths in 
Red Clay with Flints; but I believe it is the fact that, though 
Mr. Harrison has found them on the surface of Red Clay with 
Flints, as defined above, he has never found them in any Clay 
which has not contained Southern Drift; and I doubt if Mr. 
Bullen’s implement, also referred to by Prestwich, was found in 
the Red Clay with Flints. 
It is satisfactory to those who hold that eoliths are only to be 
found in Southern Drift, or gravels derived from same, that no 
forms of that description were found in these undisturbed beds of 
