f the field, the
superfluous water soon disappeared. Even now, when drain pipes are
laid in the furrows, it is not advisable to level the ridges, because
the water would take much longer to find the drains, and the growing
crop would be endangered. It is not safe to drain this land deeper
than about 2-1/2 feet, and many thousands of pounds have been
misapplied where draining has been done on money borrowed from
companies who insist upon 3 feet as the minimum depth for any portion
of the drain, which would mean much more than that where the drain
occasionally passes through a stretch of rising ground. As proving my
statement that 2-1/2 feet is quite deep enough, I have seen great
pools of water after a heavy rain standing exactly over the drain in
the furrows, and we had sometimes to pierce the soil to the depth of
the pipes, with an iron rod made for the purpose, before the water
could get away.

On light land, the subsoil of which is often full of water, the case
is quite different, and the pipes must be laid much deeper to relieve
its water-logged condition; but on our stiff clay the subsoil was
comparatively dry, and we had to provide only for the discharge of the
surface water as quickly as possible, where the solid clay beneath
prevented its sinking into the lower layers.

In the subsoil of the lias clay there are large numbers of a fossil
shell, _Gryphea incurva_, known locally as "devils claws"; they
certainly have a demoniac claw-like appearance, and worry the drainers
by catching on the blade of the draining tool, and preventing its
penetration into the clay.

I have heard the suggestion that our highly banked ridges were
intended to increase the surface of the land available for the crops,
just as it takes more cloth to cover a hump back than a normal one,
but of course the rounded ridge does not provide any more _vertical
position_ for the crop, and the theory cannot be maintained. Some of
these ridges, "lands" as they are called, are so wide and so elevated
that it was said that two teams could pass each other in the furrows,
on either side of a single "land," so hidden by the high ridge that
they could not see one another; and I myself have noticed them on
abandoned arable land that has been in grass from time immemorial, so
high as nearly to answer the description. Though the blue clay in the
Vale of Evesham is so tenacious, it works beautifully after a few
sharp frosts, splitting up into laminations t