Belfry Bulletin Number 045

The

Belfry

Bulletin

THE JOURNAL OF THE BRISTOL EXPLORATION CLUB Volume 5 No.45

March 1951

We very much regret that this issue of the Belfry Bulletin has been seriously delayed by various changes that have taken place in the Club organization. We hope that this issue will be followed by the April number shortly, and that, things will return to normal with the May number.

Club Organisation The Committee has to announce with the deepest regret the resignation of Mr. T.H. Stanbury from the position of Secretary which he has filled for so many years. Sybil Bowden-Lyle has also resigned as Assistant Secretary. The club owes these members a great debt of gratitude for the grand work they have done, much of it quite unknown to members outside the committee.

A very considerable re-organisation of the Committee’s work has been called for by these resignations.

The present set-up is as follows: General Secretary D.H. Hasell Caving Secretary M. Hanam Climbing Section Secretary R.W.G. Cantle Ladies Representative Miss J. Rollason Hut Warden R.A. Setterington Librarian J.W. Ifold Editor B.B. W.J. Shorthose (London section) Publisher K. Dobbs.

Tackle Office G.T. Lucy In addition to the above who constitute the Committee, R. Ifold is acting as Sales Secretary.

This list, with addresses, is reproduced on the back of the library list circulated with this Bulletin, and all members are asked to ensure as far as possible that they address their enquiries to the right official in the first instance.

ANNUAL GENERAL MEETING Owing to the re-organisation mentioned above, we regret that no report of the Annual General Meeting is available for this issue, but we hope that it will be possible to include it next time.

The Growth of Stalagmites and Stalactites PART II by R.M. WALLIS In the first part of this article we showed that the change in pressure which a water drop undergoes on appearing on a cave roof must be considered an essential part in the forming of a stalactite. This feature can only occur once to each drop, so how is it that stalagmites are formed? We have seen that the calcium carbonate appears in the drop as very small particles which are drawn into a ring round the edge. This process of course takes time and if the rate of drip is relatively fast only a small amount of carbonate will be left on the roof. The rest will fall with the drop, which will then trickle over the stalagmite and the rest of the carbonate will be deposited. The relative sizes of the –mite and –tite are thus seen to depend on the rate of drip. A slow drip will give a large stalactite and a small stalagmite; a fast drip vice versa.

FLOWSTONE and other deposits covering large areas occur in the same way as stalagmites, the water appearing in some crack in the wall and the carbonate being deposited as the water trickles down.

BB45/2 Helictites are fascinating objects and their formation is very much of a mystery. In the past people have tried to explain them by suggesting their growth as followed spider’s webs or has been deflected by draughts and many unlikely explanations. One theory which has some evidence to support it is as follows: - Down the centre of all stalactites is a fine tube through which water is delivered to the tip. If this tube is relatively large so that more water is delivered than can evaporate a normal straight pendant is formed. But if the tube becomes blocked so that evaporation is more rapid than the delivery an erratic appears. The theory is based on laboratory experiments in which stalactites were grown using saturated solutions of various salts, but not, of course, using calcium carbonate as the experiments would take too long. No account was taken of the drop in pressure effect and it is difficult to see how this would apply in this case. Saturated solutions were also used which do not necessarily occur in caves. This is, however, the only theory which has anything to recommend it, and it may be that helictites can only occur where evaporation can occur to a considerable extent.

Cave pearls are rather caver’s treasures. They are formed by the deposition of successive layers of carbonate round a nucleus – often a grain of sand. They occur under drip which must be within a closely defined degree of heaviness as it has to fulfil two functions; 1 to allow deposition to occur round the nucleus and 2 to rotate the pearl so that deposition occurs evenly. The drip therefore must be fairly heavy but if it is too heavy deposition will not occur. This also accounts for the well defined limit to which pearls will grow, as when they get too big they will not rotate and become cemented into a general mass of stalagmite and disappear.

Crystal pools are among the most beautiful of cave formations.

The crystals are formed actually in the water. A basin in the floor catches drips – generally a well concentrated solution and a slow drip will be needed. Evaporation must occur from the surface of the pool, sufficient to maintain the water level more or less constant, so that a saturated solution builds up in the pool.

Carbonate is therefore deposited from the water and crystals grow around the sides and spread out over the surface.

There is still a great deal of work to be done in investigating the mechanism of dripstone formation, for facts on which to base arguments are lamentably few. It is hoped that some time, some energetic people with plenty of time will get down to finding a few more, when present theories may be strengthened or new ones have to be produced.

1950 PHOTOGRAPHIC COMPETITION Those who were unable to attend the A.G.M. may be interested to hear that last year’s photographic competition was a great success. The general standard of the prints submitted was quite encouraging, and the meeting voted unanimously in favour of running a similar competition for 1951. So get busy, you budding Mortimers, and those of you with five-bob Brownies. Further details in next issue.

The first prize went to Tim Kendrick for a photograph taken in Swildon’s Hole, for which he receives a year’s season ticket to the Belfry. The second prize went to R.M. ‘Pongo’ Wallis for his picture of Tratman’s Grotto. He won’t have to worry about his B.E.C. sub this year. In the non-caving section, the only prize awarded, a Belfry season ticket went to R.A. ‘Sett’ Setterington. The third prize, a week’s Belfry fees, went to G. ‘Tom’ Ratcliffe. Congratulations to the four of them! There was also a special prize of ten shillings worth of photographic supplies for Ken Dobbs who took the best photograph with a cheap camera.

To Ken we offer our sympathy.

The judges have made the following general comments on the entries, and they are reproduced here in the hope that they will prove helpful.

"There are a few criticisms that can be levelled against many of the prints submitted. Firstly it is clear that many of the entrants who did their own printing should pay far more attention to matching up the grade of paper used with the negative. This is clearly seen by reference to some of the better prints where the quality is excellent. Much more care is also required in most cases in ‘spotting’. In many cases no ‘spotting’ has been attempted, and where it has been carried out, with two notable exceptions, it is very clumsily done and the final result is probably worse than the original print. The standard of mounting generally was extremely low. Most of the mounted prints submitted would have been better left unmounted.

BB45/3 It docs not require any great skill or experience to trim a print so that the edges are straight and the corners square, and attention to this point would amply repay the trouble involved. The drawing of lines round a print after it is mounted is very much to be recommended and helps to make a finished job, but here again, spacing is important. Where prints are titled, this should be done neatly. If this is beyond the capacity of the individual it is far better to put the name on the back”.

D.A.C. W.J.S. Court Circular Hearty congratulations to Angus Innes and Margaret Pope on their recent marriage. Our best wishes to both of them and some sympathy too! We hear Angus did it while on embarkation leave.

Our best wishes also to Ron (Holler-in-the-night) Newman and Jean Treble who also recently got into double harness. Some sort of editorial comment seems to be called for…. One “BB”, four members of the Club, two weddings….Is this a record?

Addresses of Club Officers.

GENERAL SECRETARY

CAVING SECTION SECRETARY

CLIMBING SECTION SECRETARY

SALES SECRETARY

LADIES REPRESENTATIVE

LIBRARIAN

EDITOR, BELFRY BULLETIN

O/C BELFRY BULLETIN CIRCULATION

HUT WARDEN

LONDON SECTION SECRETARY

Mr. D.H. Hasell, 1, Stoke Hill, Chew Stoke, Nr. Bristol.

Tel. Blagdon 432.

Mr. N.N. Hamman, 14, Vyvian terrace, Clifton, Bristol. 8.

Mr. R.W.G. Cantle, 46, Cherrington RFoad, Henleaze, Bristol. 9.

Mr. Roy Ifold, 32, Cobourg Road, Montpellier, Bristol 6.

Tel. Bristol 58545 Miss Jill Rollason, 137, Pen Park Road, Southmead, Bristol. 1.

Mr. J.W. Ifold, Leigh House, Nempnett, Chew Stoke, Nr. Bristol Tel. Blagdon 432 Coase and Shorthose, 26, Gateside Road, Upper Tooting, London S.W. 17. Tel. BALham 7545 Mr. K. Dobbs, 55, Broadfiled Road, Knowle, Bristol. 4.

Mr. R.A. Setterington, 21, Priorswood Road, Taunton, Som. Mr. W.J. Shorthose (Address above)

BB45/4 ARCHAEOLOGICAL SECTION SECRETARY

Mr. K.S. Hawkins, 9, Quarrinton Road, Horfield, Bristol. 7.

CLIMBING SECTION COMMITTEE:R.W.G. Cantle, (Hon. Sec.) J.R. Crabtree, (Hut Warden.)

J.V. Morris, P. Ifold, R.A. Setterington.

Members may wish to remove this page from their copies of the Belfry Bulletin and keep it for reference when writing to Club Officers. The space below may be useful for noting any changes which appear in the Bulletin from time to time.