Jester

More!

- Aspects of Caving -

Jester

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.

Revised:

Valid HTML 4.01 Transitional