This essay was originally published in British
Caver over 70 years ago. Despite its age,
much of the content is still relevant today. It also
gives a good insight to the attitudes of the early Mendip
cavers.
NOTE 1: The theory that the Mendip gorges are
the remains of unroofed caves was commonly held at the time the
essay was written, but todays evidence does not support this
view.
NOTE 2: I have inserted a few paragraph
breaks to make the text rather more readable on the screen, they
are marked thus, ¶
Aspects of Caving
by D. Ryan and E. Mason.
British Caver 2 16-24
(1938)
It goes without saying that most people whose
experience of caving stops short at the tourist parts of Cheddar
and Wookey Hole caves regard our exploits with the amused
tolerance which is usually given eccentrics and harmless
idiots. When some acquaintance hears of our peculiarity for
the first time, we all know that inevitable question...
"Why
do you go caving? What GOOD is it?"
.....as if one could easily
give the reasons for games, cinemas, drinking, motoring, or any
other pastime and as if we patronised these because of their
uses! The best reason for doing anything is the fact that
we like doing it and it's a pity that this reply sounds
somewhat rude. However, some sort of answer must be given
and as most cavers cave for sport, we usually put forward this
side first.
¶ There is perhaps no other sport which
exercises so many parts of the body, faculties of the mind, and
develops the vocabulary so rapidly as every beginner realises
after having squeezed through Sidcot or having descended
Eastwater. Within a few miles of one's home is the most
unusual scenery one could wish for, the most strenuous exercise,
the lure of discovery and exciting achievement, and all this is
enhanced by the sense of danger without which most sports would
lose their appeal. We cannot all take the time off to
explore the tropics or the poles nor even indulge in
mountaineering every weekend, but why worry, when the thrill of
all these awaits you almost on your doorstep.
¶ Then, unless your cave is peculiarly
liable to flood, there is no ceasing of activities at the
approach of winter, ... no last minute cancelling of expeditions,
no vain waiting for clement weather, for caves give shelter from
extremes of temperature, rain, fog, gale and in this climate,
such a condition would be a great recommendation for any
sport. Then there is the complete reversal of conditions
and standards of ordinary life, the shaking off of the
conventions of civilisation to wallow in mud, squeeze through
impossibly small holes and to swing out into some dark
abyss. We are so used to the extraordinary comforts of
modern life that it is only after we have spent hours in and out
of icy water that we can really appreciate a hot bath, and only
after we have worn rags drenched and dripping with mud that we
realise the merits of clean, dry clothes. In fact, if as it
is said, change is the essence of recreation, then caving is the
ideal sport.
However, the charms of mud and sharp rocks may
fail to move the sceptic and we have to fall back on the useful
and scientific aspects in our defence of caving. The
British Speleological Association's Water Survey for the
Ministry of Health is foremost in caving minds these days and
will surely impress your critic. Most of you have been
working on our area in East Mendip, both surveying and
swallet-digging and you know that is a work of some magnitude.
Water is one of the fundamental needs of life and all information
concerning it must of necessity be of importance. Information is
available from the Ordnance Survey regarding surface water
systems and geologists may deduct the supply of water available
in the water-soaked rocks, but the speleologist alone can map out
the intricate labyrinth of underground waterways and trace the
rainfall from the point where it enters the ground to the place
on the lower land where it emerges as a spring or as a
stream.
¶ There have been cases of the pollution of
water, before it entered the ground, which has been a great
trouble and danger to the villages where it emerges, and these
problems have only been solved by a study of the cave
systems. Every square yard of the cave area has to be
covered, the drainage marked in, the underground water systems
explored and surveyed, the course of the water traced out to the
point of emergence and numerous tests carried out. Complete
knowledge and control of the water system of a country is of the
greatest importance to the health of its inhabitants and the
speleologist today is able to fill the gap in hydrology.
This alone would answer the question "What good is
caving?"
However we cannot do this work properly without a
foundation of scientific knowledge and as water-systems are
directly dependent on the geology of the area, a study of this is
important, not only to the speleologist working on this
water-survey, but also to the sporting caver. As in most
other sports and sciences, we find that we cannot keep within the
limit of the sporting side of caving, but sooner or later are
drawn into one aspect after another until we become an all-round
speleologist. We may start off as a sporting caver, but
when we have exhausted all the known ways of the under-world, we
soon begin the hunt for unknown caverns. We quickly realise
that in practically all open caves other enthusiasts have been
before us. For instance, can there be any open caves in the
Mendip area which have not been described in Mr H. E. Balch's
admirable publications? We find that new caves have to be
dug for. Where and how to dig is the next problem, and to
answer this correctly an elementary knowledge of the formation of
caves and of the geology of Mendip is necessary.
Most of you are quite well aware of the formation
of cave systems and the varied stalagmitic forms which is the
beauty of underground scenery, but, a brief summary may not be
out of place. The rock in which caves are found is
Carboniferous Limestone which consists chiefly of a form of
calcium carbonate. Rainwater contains a certain amount of
carbon dioxide gathered from the atmosphere and vegetable and
animal matter. This solution reacts with the calcium
carbonate gradually eating it away forming underground
cavities. Water naturally takes the easiest course and so
it is along faults, and the joints and planes of the rock that
the caverns are formed: thus it is of the greatest
importance to the cave-hunter to have as much information as
possible about the lie of the rock. Then the important
factor of erosion comes into play to supplement the work of
solution, for material carried down by the swirling stream
hollows out the sides of the cavity. Masses of rock so
undermined give way and so the formation of the cavern goes on,
often creating huge chambers and extensive passages.
Water has slowly eaten away the calcium carbonate
of the rock and so, as though to even things up, when the drops
of this water on the roof, sides and floor of the cavern
evaporates, it leaves this mineral behind it, in the form of the
stalactites and stalagmites, whose weird beauty is the chief
fascination of underground scenery. Those which cover the
floor and which rise in bosses and pillars are called stalagmites
and those which hang from the ceiling are called
stalactites. The rate of growth of stalagmite sometimes
proves useful in determining the age of stalagmite-covered
relics.
However we may be well aware of the history of
caves and their scenery, but the question of where to look for
caves and swallets in the first place is another matter.
Open caves provide no great problem. It is obvious that
caves such as Wookey Hole Cave are found where rivers rushing
down their underground channels have forced their way out on
reaching the junction of the limestone and the later rocks.
It is believed that Caves (or swallets) such as those small caves
(or swallets) on the face of Burrington Combe and the upper part
of Cheddar Gorge were parts of the great cave system when the
Gorge and Combe were caves themselves. The roofs have
collapsed leaving these side passages as open caves.
Now as practically all open caves have been
investigated and the cave explorer is chiefly interested in the
locality of unopened swallets, to find the answer to this problem
we have to consider the general geology of Mendip. Imagine
a great arch or anticline consisting of various bands of rock,
Old Red Sandstone in the centre, Carboniferous Limestone Shale
next, then the cave area of Carboniferous Limestone, and the
later Triassic deposits on the ends. The rain falling on
the Old Red Sandstone is absorbed by this rock as sponge absorbs
water and springs out on the junction of this rock and the
Carboniferous Limestone Shale. The shale will not allow
water to sink through and so it flows as a surface stream until
it reaches the Carboniferous Limestone itself. There it
sinks through cracks and fissures in the joints of the rock,
gradually forming the cave systems with which we are
concerned. The streams flow through the cave systems which
they have made, emerging as springs in the later deposits on the
lower land. Read's Cave is an example of this.
Here you can see the Old Red Sandstone of Blackdown which absorbs
the rainfall and sends the stream through the shale valley to
sink to earth in Read's Cave.
Now it is obvious that the majority of promising
swallets will occur in the Carboniferous Limestone near the
shale, particularly on fault lines. All this information
will be found in a geological map of the area, which should be
brought up to date as much as possible with details obtained from
any geologists, who have done subsequent research on the
district. As a matter of fact we, in our area, have
superimposed the outline of the strata on our 6" working
maps and thus have the basic data for our work. When you
have located your swallet, a geological section through it,
prepared from your map, showing the dip of the rocks, will give
you the likely position of your cave system. The system
under Thrupe Swallet, for instance, should lie, when it follows
the bedding plane, at an angle of 37°
running S.S.W.
As in most other subjects, we find to our sorrow
that there are exceptions. For instance around Thrupe a
surface clay extends over quite a large area, holding up the
water and thus making streams possible over the limestone.
As soon as the clay ends however, the stream disappears
underground. One stream, which we have followed, flows
along a bed of clay and goes to earth in half-a-dozen different
spots along its course where the limestone has come to the
surface.
So much for these aspects of caving and their
uses, but sooner or later the cave-hunter, digging away at his
swallet, comes across bones. Most likely they are not very
old, merely remains of modern animals washed down by the
stream. At Thrupe we have found bones of dog, horse, brown
rat (which in itself dates the associated bones, since this
animal was not known in this country until 1728/9), and from
lower down the stream-bed, wolf and wild boar, together with
pieces of Roman glass and pottery, all scattered amongst the
boulders, evidently washed in by the stream.
However, bones old or new have a peculiar
fascination -- as is proved by the excitement with which some
swallet-digger unearths the remains of a cow, or by his pride at
finding some teeth of a dog a few years dead -- and so we turn to
the most important side of cave sciences:
Cave-Archaeology.
This aspect of caving has supplied so much of our
knowledge of ancient man that it is itself an entire
justification of speleology. During pre-historic times,
caves were man's best shelters from exposure, from the fierce
attacks from powerful animals of those times and from his
enemies. Through the ages, until comparatively modern
times, man has turned to the caves again and again in troublesome
times. Indeed Nancy Camel's Hole near Croscombe and
Pride Evan's Hole in Cheddar Gorge were inhabited as recent
as the early ninetienth century.
Paleolithic man often had to fight the powerful
animal occupants for possession of a cave, as good shelters were
rare and much sought after. If succesful he and his family
would live there perhaps for generations, while their discarded
implements, bones from their meals etc. would pile up on
the cave floor. Then perhaps the inhabitants wou1d move for
some reason or disaster might overtake them and their remains
would lie in the cave among their positions. Perhaps for
many years a cave would be vacant and earth and debris bury the
signs of habitation, until a new race of animals or man took
possession. The floor of a cave is like a book, each page
telling the story of an occupation, and it is the excavators'
job to interpret these records.
By uncovering the layers one by one, mapping and
photographing, by standardised methods, the remains in their
original positions, one can trace the story of the cave's
inhabitants from the most recent to the earliest, unearthing a
record of their physical characteristics, their implements, the
animals of thier time and thier ways of life.
It will be well understood that the value of
these relics of ancient man is not so much in the objects
themselves, but in their association with each other and the
stratigraphy of the cave deposits. That is why an unskilled
caver digging for "bones" can irrevocably destroy the
most valuable evidence, for once the deposits are disturbed most
of their value is lost for ever. As you all know it is a
rule of our Society that members shall not undertake any work on
behalf of the Society without the sanction of the Committee, but
we would urge that no work of this nature should be done without
the supervision of a competent excavator.
¶ At the last Conference of the B.S.A. our
attention was drawn to yet another way in which caving can
contribute to scientific knowledge, and that is by the
investigation of cave fauna. Owing to the lack of light and
vegetation, animal life, except bats, is very scarce in caves,
but a few forms of life have been able to adapt themselves to
cave conditions and are now found only underground. Such
are the colourless, blind fish which live in the underground
rivers in Kentucky, such is the white newt, exhibited at the
Conference, found in a culvert of London. These forms of
life have not been investigated to any great extent and it is
only through the co-operation of cavers that zoologists can fully
study them. Various types of nets are available for the
Societies who wish to take part in this work and their job is to
fix them in suitable places in caves and collect them and send
them back with their contents after a certain period. A net
has been placed by this Society in the stream-bed in Stoke Lane
Swallet. We started off by answering a question and seem to
have ended by giving a lecture. After this we hope that
nobody will dare broach the subject again. After all, the
sportsman caves for his own pleasure and credit, but the
speleologist who is willing to study and to work with patience
and accuracy, may add something, however small, to scientific
knowledge for the benefit of all.
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