Belfry Bulletin Number 227

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No 227 January 1967 The Belfry Bulletin – Volume Twenty One – Number 1 We would like to wish all readers a very happy 11/12ths of a New Year. It has taken rather longer than expected to recover from the Christmas bumper number, and most members will not be getting this one until January is over. With luck, however, we hope to catch up.

Somebody suggested that now the B.B. has entered its 21st volume, it can be said to have come of age.

This suggestion was countered by the Editor (who had visions of having to produce two large B.B.’s in a row) by pointing out that the B.B. was first produced in January 1947 and thus it will not be 21 until next January. Still, it’s a thought and perhaps some older members who remember early B.B.’s might care to comment by writing something for a “Twenty First Birthday” number. You have a year to produce something, so there isn’t much excuse.

“Alfie” _______________________________________________________________________________________

Notices Goon Suits.

The club are arranging to get Goon Suits from a source in Scotland for sale to members at 40/-. These will be down on Mendip at Easter. Meanwhile if anyone is feeling desperate/affluent, one can buy Goon Suits at 50/- from the Army Surplus Stores (Hotwells Rd. & Grosvenor Rd.).

NiFe Cells.

These are available from Alan Coase at 42/6 delivered or 35/- when Alan is on Mendip.

Write to: - A. Coase, 35 Broughton Road, Croft, Leicestershire. _______________________________________________________________________________________

B E C Survey Course The first B.E.C. course on Surveying is now fully booked up, but it is planned to run a further course if demand persists. For the benefit of those who may wish to consider having a go the course runs over three days – two on one weekend and one on the next. The first course is on the 18/19 of February and the 25th as follows Saturday 18th February. (At the Hunters.)

10.30 – 11.

11. – 12.

12. – 1.

2.30 – 3.

3. – 4.

4 - 5.

Reasons & Aims of Surveying.

Low Grade Surveys.

High Grade Surveys.

Instruments.

Calculations.

Drawing and Presentation.

(S.J. Collins.)

(D. Irwin.)

(R.D. Stenner.)

(R.D. Stenner.)

(B.M. Ellis.)

(D.J. Irwin.)

Sunday 19th February.

Practical work. Surveying in the Railway Tunnel and/or Rabbit Warren areas of Cuthbert’s. Alternatively in Goatchurch and Avelines.

Saturday 25th February. (At the Hunters.)

2.15 – 3.30 3.00 – 4.30

Calibration of Instruments.

Discussion.

(D. Warburton.)

Page 2 The method of tracing streams by the variation of hardness and water temperatures was described as an interim report by Roger Stenner in the Christmas B.B. (Volume XX). Here is an actual example of the method in use.

The Maypole Sink (The Location of the Maypole Sink without the aid of Chemicals) The temperature of the Maypole Series stream is sometimes significantly different from the rock temperature at that depth in the cave. Readings taken in December 1965 showed: Maypole Stream, Traverse Chamber Main Stream, Water Shute Kanchenjunga Drip

8.60 8.55 8.95

All temperatures being in degrees centigrade.

This would indicate that the source of the Maypole Stream is a local swallet. An analysis of water samples taken in May 1966, gave the following results for water hardness (In parts per million of Calcium Carbonate).

St. Cuthbert’s Pool Plantation Stream Maypole Series Stream (Long Chain Pitch) Pulpit Passage (East Inlet Stream)

148 ppm 114 ppm 143 ppm 150 ppm

The fact that the Maypole Stream is softer than water from S. Cuthbert’s Pool proves that the pool cannot be the sole source. Admixture with softer water is indicated.

A swallet exists as in the sketch on the next page, in which water from St. Cuthbert’s Pool is mixed with the softer Plantation water. No other local swallet fulfils these requirements, and it must therefore be the Maypole Sink.

This swallet has long been thought to be the Maypole Sink. The survey points to a source in the vicinity of the swamp I have drawn as the St. Cuthbert’s Pool, but hitherto this belief had remained unproven.

R.D. Stenner _______________________________________________________________________________________ We have received the following from “St. Cuthbert”: To the Editor, Belfry Bulletin.

Dear Sir, I am so glad my letter sparked off such delightfully witty replies. What a pity their authors chose to hide their talents under nome de plume.

Yours Faithfully St. Cuthbert _______________________________________________________________________________________

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Long Term Planning - 3 There were no further letters from members to the Long Term Planning Committee at their last meeting.

Some progress was reported on moves to assess the Government Grant for possible snags, and the proposal to explore the possibility of making the club into a Company limited by guarantee.

The main subject of the month was that of Situation. What could we best do with our present site, or even should we stay on it? It was decided that we ought to stay for a variety of reasons. We have agreed to do all we can with a view of seeing how best to fit in with our immediate neighbours, and to re-open negotiations with the Paper Mill to see if we can buy some more land adjacent to the Belfry Site. If we can do that we may be able to alter the position of the track and there is a scheme to see if we can purchase the other track (the one which used to lead to Art Dor’s milking shed) so that we can let Walt use it and close the present “Belfry Avenue” to all except the club.

The Old Barn was also discussed. The Committee arranged to buy this for £50 last year for a variety of reasons – mostly as an insurance against various eventualities. It was decided by the Long Term Planning committee that we should hang on to this, and not try to dispose of it. It could well prove a long term asset to the club.

We are also going to ask the Hon. Treasurer at the next meeting of the General Committee to start collecting money by any means that he can at present as we feel that a certain amount of this type of exercise could begin now, even before the club have been asked to decide.

Next month, the Long Term planning Committee are going to review what they have done to date, so if any member has any point of view to express, now is the time!

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Swildons goes to Wookey A five year hydrology study of the underground water distribution on Mendip is being undertaken by Dave Drew in connection with the Water Board. Eventually, a full report on this will be published, but some of the findings to date are of interest.

Lycopodium spores (which are seeds of the Club Moss and being extremely small and light are ideally suited to this type of exercise) were put in the streams entering a number of Mendip Caves at noon on New Year’s Day 1967. The first samples form the resurgences at Wookey and Cheddar were then collected eleven hours later. Results from then were as follows: Cuthbert’s (Via Plantation) Eastwater Swildons August/Longwood Manor farm (U.B.S.S. Dig)

11 hours 16 hours 25 hours 20 hours 20 hours

To Wookey To Wookey To Wookey To Cheddar To Cheddar

Spores placed in various caves were stained to that their origin could be sorted out at the resurgence.

With the sole exception of Cuthbert’s, all the times are the transit times from entrance to resurgence. In the case of Cuthbert’s the first sampling and so the actual time may well have been much quicker than the 11 hours noted. In addition, it is known that water takes approximately 1½ to travel from Wookey 15 to the entrance. Thus from the entrance of Cuthbert’s to the first known upstream place in Wookey must take less than 9½ hours. The time taken for the water to travel from the entrance of Cuthbert’s to the sump must be subtracted from this total, and we are left with the conclusion that water travels extremely rapidly across the unknown gap between Wookey 15 and Cuthbert’s Sump, which supports the theory that some of this distance could well be open passage rather than seepage below the water table. Let us hope that at least some of this conjecture will be removed by the forthcoming diving op. in Cuthbert’s Sump. _______________________________________________________________________________________

S u r v e y in g C u t h b e r t s …by Dave Irwin.

Early in 1966, it was decided to commence a new survey of the know system at a minimum of C.R.G. Grade V that would be published in parts with the ‘definitive’ publication on the cave. The reader might well ask “why?” when so much has been done in the past. The lack of passage detail and permanent stations is the simple answer, which made the tying in of side passage extremely difficult. It is hoped to make the survey a complete one, including all passages where practical – if any one would like to survey the route through the boulder floor of cascade Chamber they are welcome!

A large traverse of the main cave is almost complete – when it is closed it will form the basis of the survey. (Plantation Junction – Stal Pitch – Cerberus Series – Everest – Boulder Chamber – Pillar Chamber – Wire Rift – Pulpit – Traverse Chamber – Upper Traverse Chamber - Harem Passage – Rabbit Warren and back to Plantation Junction.) In addition to this, the Mud Hall area (between Rocky Boulder Passage and the New Stream Route) Rabbit Warren to Sump and Cerberus series are almost complete, together with numerous traverse lines crossing the Cascade area (Fingers, Railway Tunnel and Boulder Chamber).

To date, most of then survey is to Grade VI and it is hoped that it will stay at that standard. As regards the survey as now drawn up, there are two surprises (a) The sump Passage runs down dip and (b) Harem passage is immediately above Bypass Passage subject to traverse correction. The equipment being used by myself is a combined mounted abney level and prismatic which is tripod mounted. This cuts time to a minimum and up to 38 legs have been surveyed in less than two and a half hours. Many thanks to Bryan Ellis for this great advance in cave surveying. Roger Stenner is using a conventional compass and a tripod to Grade VI. In each case, the ‘leap frog’ method is being used and so far has given very good results with closure error of between 0.45 and 0.9%

Page 5 When will the survey be completed? The answer to that is anyone’s guess, but the end of 1968 should be a reasonable estimate – sooner if other surveyors come forward. What about it, Alfie?

Finally, thanks to all who have helped sometime under very uncomfortable conditions – particularly Dermot Statham and Joan Bennett.