A REPORT ON INVESTIGATIONS IN THE DENEHOLES 1
A Preliminary Report on Investigations in the
Deneholes at Hangman's Wood, Grays, Essex
By D. I. Chapman and P. M. Hammond
Introduction
The recent investigations in the Essex deneholes, which have
been performed by the Essex Field Club and other organisations,
are reported in this paper. The deneholes will soon be sealed off
from the surface, unless something is done in the near future to
preserve them. Therefore, it was felt that the recent work should
be published, even though no discoveries have been made which
would solve the mystery of the holes. It is not intended to enter
the controversy as to the origin of the holes, which has been
discussed much in the past by Holmes and Cole (1883, 1885, and
1887), and more recently by Caiger (1954), although the latter
author does not mention the theory that they are natural.
The deneholes are situated in the chalk, and each hole consists
of six chambers which are arranged in what is usually known as
the double trefoil pattern. The holes are connected to the surface
by vertical circular shafts through the overlying Thanet Sand and
river gravels. The double trefoil pattern can be visualised by
considering two clover leaves placed end to end, with their stalks
together and at right angles to the plane of the leaves; the six
lobes of the two leaves representing a plan of the chambers, and
the stalks the shaft. A fuller description, together with a plan of
the holes which were known in 1887, is given in the Report of
the Essex Field Club's Denehole exploration at Hangman's Wood,
Grays, in 1884-1887, Holmes & Cole, (1887).
In 1887 the position of 51 shafts was known, and of these, five
were open. The Club entered and examined 15 of these holes,
mainly by cutting tunnels through the chalk from one set of
chambers to another set. When the present explorations were
started in October 1958, only five shafts were visible; these being
the ones numbered 1, 2, 3, 4 and 5 in the exploration of 1884-7,
and only shafts Nos. 3 and 5 were open. At the time of writing
(January 1962) only three shafts (Nos. 2, 3, and 5) were visible
and of these, two (Nos. 2 and 3) were blocked. It appears that
an attempt had been made to block the last open shaft (No. 5),
as a substantial portion of a tree trunk and other smaller debris
had to be removed before the shaft could be descended.
However, there are still many depressions in the ground, which
probably indicate the position of the other blocked shafts. There
have been many changes in the actual chambers as well as on the
surface since the Club's explorations last century. A lot of soil