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Diving Operation.

There will be a diving operation in Swildons on the 23rd of June this year.  The intention is to get a diving party into Swildons VI by the direct stream route and then to push ahead into VII and beyond until they run out of cave, sumps or divers.  A support party will be required to go into IV via Paradise Regained and Blue Pencil and to free dive into VI.  All active members having the required degree of fitness are asked to get in touch with the organiser, Mike Thompson.  Others may be required elsewhere in the cave.  These people should also get in touch with Mike, who will be glad of their help.

Midsummer Barbecue.

Owing to the diving operation, this will be held this year on the 16th June.  Names should be given to Garth.

Annual Subscriptions.

These should all be in by now.  At the risk of repeating ourselves, we quote the little mnemonic which appeared on this subject several years ago

Annual subs should all be in
Ere the month of May begin.
Any bod who fails to pay
Doesn't get B.B. for May.

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The Hut Warden would like to thank Dizzie and also John Lamb for donations of cutlery for the Belfry. He is still short of KNIVES.

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The Hon. Librarian would like to remind all who attend club on Thursdays that the Library is open every week for the borrowing of books

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It is with regret that we learn of the death of Professor L.S. Palmer on March 17th, after a six month illness.  Prof. Palmer, as most members will know, became Honorary Curator of the Wells Museum on the death of H.E. Balch, its founder.

Concretions in Balch’s Hole

by Jill Rollason.

The formations in this cave warrant a description, since (1) the editor could do with the material for the B.B. and (2) the stal is in a class of its own from the technical aspect. Generally speaking, it is re-crystallised, extremely fragile, and as clear as ice - especially the straws, which look like the "glass rain" that continental speleologists call them.

Helictites are very frequent, particularly in Erratic Passage, as is to be expected; and can only be bettered by those in the newly discovered Ladder Dig extension in G.B. Cavern. Again, they appear to be completely crystalline and transparent as ice and, although some are extremely involved in shape, many are only simple projections from straws.

However, the stalactite of Balch's Hole is probably its most individual feature.  The typical example is very pure white in colour, re-crystallised and joined to the roof by a narrow neck which gives the growth a strong resemblance to the shape of a carrot.  Some of these 'carrots' hang at the end of slender straws and it appears that they start off as a thickening of a straw and develop outwards and upwards as well - possibly in the crystalline period.  There is no simple explanation of this thickening since each 'carrot' that I examined had the straw running through the middle, and in more than one case, the interior of the straw is unobstructed.  The second interesting feature of the stal in this cave is that it is in most cases strongly phosphorescent, glowing a brilliant emerald green for several seconds after exposure to flashbulbs.  Efforts have been made to capture this effect on colour film, and a separate article on this aspect of Balch's Hole is being produced by Mike Baker.

Bug-Hunting in Cuthbert’s

by Richard Roberts

Caves are regarded by most people as completely lifeless but life underground exists, although to a markedly less extent than above ground.  Life underground requires, basically, two things.  One is water or moisture and the other is organic material capable of being broken down and digested.  Caves are usually fairly short of the latter but not absolutely bare of it. Pieces of wood or decaying leaves swept in by a stream provide excellent breeding grounds for cave fauna, but the most interest¬ing of these are out of reach of the stream, even in times of flood. Small pools way off the stream way are often full of life.  This is especially true of St. Cuthbert's.

When presenting a survey of cave life, special care must be taken to separate the habitual cave dwellers  (Troglobites) from the cave dwellers carried into the cave by accident (Accidental Trogloxenes) and those creatures which enter the cave for a certain period of their life  cycle (Trogloxenes).  We are only interested in the former.  These are usually allied to similar species above ground, but have evolved in such a way that they adapt themselves to life underground.  They lose their sight, and hearing becomes of little importance in this dark world, which is silent except for the sound of water moving and the very occasional rock movement.  Unfortunately, very little is known of their breeding habits as they are exceptionally difficult to observe in their natural environment.  This is a field of science which is comparatively unknown and a great deal of help is afforded to the expert by the amateur collector.

In St. Cuthbert's, I am starting work on a complete survey of the life-cycle within the cave and the fauna present there.  So far I have been collecting specimens from the better known parts of the cave.  This is very important because the caver tends to wipe out the colonies of insects living on these main routes.  One careless step can often destroy the work of many hundreds of years.  I decided to start in the obvious places such as the bottom of the entrance rift, which fairly abounds with several types of flies.  These must be   something in the region of twenty or thirty small flies here.  They appear to be related to the common fly present throughout the summer.  Also there is a larger, variety very similar in appearance to the Mayfly although somewhat smaller.

A thorough search in a small tributary stream entering here also led to the discovery of some life. A small colony of flat worms, about four millimetres long was living in the stream bed.  They were coloured white with small black spots along their backs. They were very similar in appearance to a young centipede.

Lower down, at the bottom of Arête Pitch, a colony of Collembola - small, maggot-like creatures about one to two mm long, which live on the surface of the water - proved a good hunting ground.  This species is very common in caves, but there are about a hundred different types of Collembola which have so far been collected in British Caves.

In Pulpit Passage, there are very many ledges on the left hand side, out of the flood level of the stream, which contain small pools.  In one of these there is a colony of blind shrimps of the order Amphipoda. These shrimps are very similar to the fresh water variety, but are completely colourless and blind.  Perhaps a colony is too strong a word for these. These were about four, but no doubt others were in the close vicinity.

Returning to the Old Route, there are several colonies of Collembola in the trench leading down to the top of Ledge Pitch.  The passage above the Wire Rift is also well populated.  Above Upper Mud Hall there are several pools which always suffer from the caver’s boot.  In the present year and a half, a flourishing colony of some forty Collembola has been destroyed.

In the lower reaches of the cave, below the Dining Room, there are several small groups of Asellus. These are very similar in appearance to the shrimps, but have ceased to move on their side and are slightly larger. In the Great Gour, and also some of the small gours a great many blind shrimps have been seen and one or two collected. It seems quite reasonable to suppose that a large number of these are living there.

Several other specimens, mainly Collembola, have been found on tourist trips to other parts of the cave. Notably, these are, the Rat Run; Rabbit Warren; Maypole Series; Harem Passage; Cascade Chamber; Everest Passage and September Series.  Here I would like to add a plea.  In September Chamber there is a small pool in the rocks near the taped formations.  It is to the left of the tape and about ten feet from the side of the chamber.  Please avoid contaminating this pool.  It contains a flourishing colony of Collembola which are of a variety which I have never before seen underground.  It would be a great shame if this was carelessly destroyed.

I would like to finish by saying that none of these specimens has yet been properly identified by the C.R.G. but the specimens can usually be identified down to the 'order' by the amateur.  If anybody is interested in starting this kind of work or helping me in it, I shall be very interested to hear from them.

Bushman Art

by K.S. Gardner.

I was very interested to read Sybil's article in the Christmas B.B. on her search for Bushman art in South Africa.  Over the years, quite a large number of B.E.C. members have got around to the Franco-Cantabrian group of deep-cave paintings and engravings, but I think this is the first recorded visit paid by a club member to the bush.  For the archaeologically minded, a few words on the comparison between the two groups might not be out of place.

The Palaeolithic art of Europe lasted over a considerable time span, possibly 25,000 years or more.  In this time, various material cultures supplanted or fused with local predecessors - Aurignacian, Magdalenican, etc, and eventually there seems to have evolved an "art for art's sake", particularly in the 'mobile' art such as decorated spear throwers etc.

Basically, however, regardless of the material culture or the art 'school' (for even then there were impressionists, cubists, renaissance etc) the underlying motive was magico-religious.  Models in clay of animals, ritually attacked with spears, paint¬ings with arrows superimposed, pregnant cows, bison in the act of mating all bear silent testimony to the rituals enacted to ensure full herds and success in the chase 20,000 years, ago.

How then, does Bushman art compare?  To start with the Bushman himself.  Probably once the aboriginal of Africa, he is small, yellow skinned and a nomadic hunter now diminished to a few thousand strong in the South African Bush.  He is not by any means a Negro, but must have been absorbed or liquidated by that race with the exception of the few thousand.  His art is found preserved in sheltered “abris” in the rocky open country of South and East Africa.  As with the Palaeolithic art of Europe, there are many instances of paintings being superimposed on earlier ones and of different styles being used.

The Bushman as he is today is apparently artless and certain schools of thought have expressed doubts as to whether he or his ancestors were responsible for the Bushman Art. According to Stow, Adams and others however, there is no doubt that, even if modern Bushmen do not paint, they understand perfectly the messages on the rock walls.

Another point in favour is that the humans portrayed are art recognizably Bushmen - short yellow men - and in several frescoes are to be seen fighting with taller Negro people. It has been recorded anyway that a boer actually watched an old Bushman at work on a fresco.

The subject of the art is usually of common wild animals with more humans than in the old European pictures.  Symbols such as Sybil’s dots are not uncommon.  Hunting and fighting are portrayed presumably in a pre-arranged attempt to ensure success.  A group of ostriches followed by an "ostrich" with human legs - reminiscent of the sorcerers and animal men of Europe - have been interpreted by Bushmen as 2 males   (black) 3 females (blue) and a 'nusa' Bushman hunter - a sub-tribe who were apparently known for this method of hunting.

The methods used are also not unlike the early European.  Hollowed out stone palettes; paints of metallic oxides ochres, and animal fats have been identified.

It has not been possible to provide a direct link between Europe and the Bush, but it does serve to show just one more instance of the almost indestructible instincts and skill of man regardless of colour or race.  From Australia to Greenland, Siberia to Africa; from 40,000 years ago to the present day, the primitive races have retained their artistic instincts and skills unaffected by the temporary gloss of 'civilised' Europe and its contemporary daubs.

Further Thoughts on Surveying

by S.J. Collins.

Bryan Ellis concluded his article last month by hoping that it might lead to further discussion of this aspect of caving in the pages of the B.B.  This article is at least one such result - I hope there will be others.

I should like to make my first point by considering the hypothetical case of the average caving type who has just bought a copy of the latest survey of some Mendip cave.  Two things are involved here to start with. Firstly, that he has paid several shillings for his copy - probably as much as he would spend on beer for a night at the Hunter's - so we must assume that he thinks the survey worth having. Secondly, the survey he has bought is the final result of much hard work by the surveyor who, presumably, had some purpose in mind when he decided to spend so much of his time and effort on the job.

At the risk of being facetious, I should like to consider both these points which are normally taken for granted and ask.  What did the caver buy the survey for?  and, Why did the  surveyor do the  survey in the first place?

I recently conducted a little survey of my own amongst some of the owners of cave surveys to ask what they use them for, and in many cases they admitted that the surveys were very rarely even looked at once purchased.  (Mike Baker mentioned an ingenious use for a cave survey which, unfortunately, lies outside the scope of this article).  The motives of cave surveyors are rather more complex, but, having done some surveying myself, I must admit that I never gave much thought to the uses of the work I was doing.

I should like to postulate three possible uses for a cave survey as follows:-

1)                  To act as an illustration when describing, discussing or planning a trip.

2)                  To act as a measuring tool for exploration or other scientific purposes.

3)                  To act as a map on which to find one's way round the cave system.

Now the C.R.G. system is excellent as far as it goes, and the advice and methods given in 'British Caving'   contain, in my opinion, nothing taut good sound sense.  The gradings, however, refer to the expected accuracy of the centre line only.

Let us start by considering accuracy.  Even experienced cave surveyors can sometimes be way out on accuracy.  On the 5th Cuthbert’s survey trip (1/12/56), a five point closed traverse taken with a metallic tape and tripod mounted astrocompass, failed to close by 11° and several feet.  On an open traverse, this error would have remained undetected. The only real check on the accuracy of open traverses is to compare them with a second set of readings - preferably independently carried out.  Such a check is available in Stoke Lane Slocker, since both Coase and Warburton have surveyed this cave.  In this case, an excellent agreement results - to the credit of both the surveyors, and the accuracy of each survey is thus removed from the realms of conjecture. What we seem to want, in my opinion, is a distinction between the present grading of expected accuracies and the cases where evidence can be brought to substantiate the claims.

Unfortunately, a direct comparison between Coase's and Warburton's surveys is not possible owing to the fact that the former is to a scale of 1:250 and the latter 1:240. This is because some surveyors work to scales based on eights of an inch and others to scales based on hundredths of a foot.  The first give scales of the type 1:48 1:96 1:240 1:480 etc and the latter give scales of 1:50 1:100 1:250 1:500 etc.   I personally favour the latter as it forces all who handle the survey to use surveyor's scales instead of ordinary rulers, and if you only want a rough guide, you can take the nearest eighths scale as being approximately correct.

Mention of scales brings us to the next point.  The amount of wall and passage detail; the accuracy to which this is drawn and the 'pictorial' quality of the survey depend largely on the scale to which the survey is drawn.  It is of very limited extra use to draw an accurate centre line survey to a large scale if advantage is not taken of the opportunity to include more of this kind of detail.  On the other hand, a less accurate survey with lots of detail, drawn up on a suitable scale, has a greatly increased usefulness.  A suitable scheme would be to agree on a range of scales and a suitable amount of detail to be normally associated with each.  As the scale got larger, conventional signs would presumably make way for a more detailed pictorial representation.    Such scales could well be as under:-

'A' = 1:50.  'B' = 1:100. ‘C’ = 1:250.  ‘D’ = 1:500.  'E' = 1:1,000.  'P' = 1:2,500 (approx 25"/mile).  'G'  = 6''/mile.

The last two would be used mainly for superimposing onto O.S. maps.  Thus, an accurate survey if a  small cave for, say, archaeological purposes, could well carry a grading of 6A which would mean that, in addition to the centre-line grade of 6, the survey had been plotted to a scale of 1:50 together with all the agreed detail appropriate to  this scale.  The same survey data, if used to add this small cave onto a map of a larger nearby system could result in, say, a grade 6D survey of the two. Surveys in which little attention is paid to detail, and hence the detail for the scale used is below standard, would just be known by a single grade number as at present.  There would be no stigma attached to this type of survey, it would just be recognised as being a different type of survey.

Which brings me (at last!) right back to my first point.  What sort of survey are we producing and is this really useful to most of the owners?

The answer to the first question, I would suggest, is that while we are no doubt attempting to caver all the uses postulated earlier, we are really only succeeding in covering the second use try means of our accurate centre line.  This has, of course, been of great advantage to those who have extended caves or linked passages as a result of survey data, examples are the mud passage in G.B. - a very useful piece of work, and the Fingertip Squeeze forcing in Stoke - a neat proof of the survey, but of little practical importance.

We are, nevertheless, mostly prepared to admit that a good centreline survey has its uses apart from its primary one in enabling connections to be found etc.  Might therefore, other types of survey only aimed at, say, illustration of routes to be taken, be of equal use?  The diagram of Cuthbert’s in the Belfry is one such survey - if you use the term in a wider sense.

It is at this point that I imagine I will be found to disagree with Bryan.  I think that every cave surveyor, when starting a cave survey, should ask himself what kind of survey he is contemplating and how best he can collect the necessary data and then present it on paper.  By all means let him use the present system, complete with C.R.G. gradings if it fits in with the sort of survey being undertaken.  On the other hand, some more imaginative surveys and presentation methods would be of great value and should in no way be looked down on. Even if they fall short of the intended aim at least they are trying to find new methods of acquainting people with a particular cave and perhaps, as a result of several attempts to introduce some new thought into the art of cave surveying, some future set of standards might emerge which will cover all aspects of the survey in a manner which will be just as universally acceptable as, say, the O.S. conventions art on surface maps.  Until then, let us experiment and work towards the day when cave surveys will fall apart from constant use in the same manner as paper backed maps!

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The Belfry Bulletin. Secretary. R.J. Bagshaw, 699, Wells Rd, Knowle, Bristol 4.
Bristol Editor, S.J. Collins, 33, Richmond Terrace, Clifton, Bristol 8.
Postal Dept. C.A. Marriott, 7'8, Muller Rd, Eastville, Bristol.