The Deneholes of Hangmans Wood
A description of a little-known
type of underground feature written by Derek Sanderson and Roger Wing.
The Deneholes are phenomena which may be of interest to
cavers - particularly as some of them can still be explored. Indeed, some members may be familiar with
them whilst others may merely have read about them. They are found in a number of counties in the
South East of England and also in parts of
DESCRIPTION. Basically, all Deneholes consist of a single shaft dropping vertically
from the surface through the thin topsoil of the region and the underlying
Thanet Sand, and terminating in a chamber in the chalk beneath, which may be at
a depth of up to eighty feet. These
shafts vary in diameter, but are usually between ten and twelve feet wide and
are reminiscent of a well shaft. The
chambers at the bottom vary in shape from simple bell like chambers to more
complex chamber patterns. The Deneholes
found at
AGE. To establish
their age is by no means easy, but one may hazard a guess from various pieces
of evidence. In 1884 and 1887, the
Deneholes complex of Greys was fully investigated on behalf of the Essex Field
Club by two of its members - T.V. Holmes and W. Cole. An extensive report was published in which
they discussed some of their findings. They found, for instance, pieces of Niedermendig lava which was quarried
in the
The most useful evidence concerning age comes from the bones
found in the deposits that have inevitably settled at the bottom of the
shafts. These include remains of sheep;
badger; ox; dog; horse and man. What is
significant is the total absence of
One may suggest, then, that the Deneholes were dug soon
after the arrival of the Normans, and this seems to be the conclusion arrived
at by Baker when he wrote, '
the assumption that they existed in Saxon times
will hold no more water than a chalk Denehole would.' (Caving, p102). They do, however, predate the trees which
grow around them.
REASON FOR EXISTENCE. This leads to the engaging problem of why they are there, and several
theories have been put forward over the years.
- The
shafts are, in fact, natural. This
is a recent theory. What has been
supposed is that a cavity has been formed in the chalk bed by percolating
water in a similar manner to that which occurs in Limestone. This cavity is formed close to the top
of the chalk layer. The theory goes
that eventually the roof of the cavity meets the underside of the layer of
Thanet sand above, and this drains through like an egg-timer to leave a
cylindrical shaft dropping into a semi-filled chamber in the chalk
beneath.
No matter how feasible this theory may seem, it cannot hope to explain the double trefoil shape of the chambers. Add to this the problem of balancing the infill with the volume of the shaft, and the theory loses credibility - regardless of whether such a formation process is at all feasible. - An
equally implausible view is that they were gold mines. 1705, a Dr. Pert wrote a Natural History
of Oxfordshire, in passing, he referred to the Deneholes as 'the gold mine
of Cunobeline in Essex.'
- That
they were flint mines. There are
several points against this view. Firstly, a band of flint can be seen in both the open shafts of
Hangman's Wood, but this flint has not been touched. Secondly, there are no signs of debris
either inside or outside the Deneholes, and this would be the first time a
flint mine had been cleared up.
- That
they were Roman burial chambers. Some burial urns were found by a Mr. Neeson, but not in the
Deneholes of Hangman's Wood, and both the dating and design of the
chambers run against this view.
- That
they were cave dwellings. Clearly,
this is wrong. Cave dwellings are
invariably littered with the remains left by the inhabitants. No such remains have been found in
Hangman's Wood.
- That
they were places of refuge. According
to Baker, this theory seems to have gained weight from the fact that
locally, the word 'Denehole' is pronounced 'Danehole' implying a hiding
place from the Danes. However,
several commentators, including Baker, have observed that the word is derived
from the Anglo-Saxon word 'Denn' which simply means 'Cave' or 'den'. Also, the nature of the Deneholes
themselves suggests that they are the last place that one would wish to
use as a refuge. Once in, it would
be an easy matter to become trapped.
- That
they are pitfalls, or some form of animal trap. Clearly, this is not a feasible theory,
as the Deneholes are too elaborate in construction.
- That
they were granaries. This theory
was much favour by Holmes and Cole, and they arrived at this conclusion by
drawing an analogy between the Deneholes and other under ground
constructions which are definitely silos. However, where these silos are concerned, there has always been an
abundance of evidence as to their use - evidence which the Deneholes have
not displayed.
- That
they were chalk mines, either for local marling or for commercial
uses. This theory seems to be the
most likely, and was accepted by Baker, though a few questions may still
spring to mind. Firstly, why mine
chalk at Hangman's Wood when there is a large outcrop of the rock barely
two miles away? There may be
several possible answers to this, such as the cost or inconvenience of
transport, or different ownership of the land where the outcrop
occurs. Secondly, why are the chambers
shaped the way they are? Baker
attempts to explain the trefoil shape in terms of how far a bucket on the
end of a rope will swing from the main shaft, but this is not completely
satisfactory. Rather they are
shaped in this way for purposes of structure. Some of the walls between chambers of
one shaft and another are only a matter of feet thick, so they have been
dug with a sense of precision. There is very little evidence of collapse which implies that the
diggers knew when to stop digging 'one chamber and start another. The trefoil shape may be the natural
outcome of the maximum removal of chalk with the minimum of risk.
SIGNIFICANCE OF AGE. It may have been noted that the Deneholes at Greys were tentatively
dated as post-Norman, while elsewhere Mr. Meeson found some Roman urns
suggesting a pre-Norman date. The
conclusion to be drawn from this is that not all Deneholes were dug in the same
period and that they were dug when and where necessary. This would imply that, whatever their purpose
was, it was an agricultural or industrial one rather than being the result of
an invasion or some other occurrence which can be accurately dated.
ACCESS. Access is
controlled by Thurrock U.D.C. who issues a descent licence for those who are
prepared to abide by a number of simple rules and fill in an insurance
slip. Address to write to is: Recreation
Manager, Recreation Department,
References
Caving (E.A. Baker)
Forgotten Thameside (Glyn H. Morgam) 1951.
Deneholes and other Chalk Excavations (Rev. J.W. Haynes)
Journal of Royal Anthropological Institute.39,1909.
Essex Field Club Report. (T.V. Holmes & W. Cole)
Naturalist. Vol 1,1887.
