Belfry Bulletin Number 157

March 1961 Vol XV No.3

Number 157

Page 1

March 1961 – No 157

_______________________________________________________________________________________ February Committee Meeting.

At the February meeting of the committee, G. Selby; John Ransome, Mike Garton, Chris Hawkes (Hawkes of Leicester!) John Tierney were all elected as full members and Norman Tuck was elected as an associate member. We should like to welcome then all to the club.

Bunks will be transported to the Belfry in a few weeks, to be made into a portable stack to go either in the Ladies Room or in the living room as the occasion warrants, so that the accommodation at the Belfry will be further increased and advantage nay be taken of the extra room in the Ladies' Room.

It was agreed to alter the membership forms to include the signature of the parents in the case of members who are under twenty one. A new class of membership was also agreed to. This is Associate Life Membership and it will cost £3/5/-. This will include the status of associated, combined with the life member’s permanent membership.

The Climbing Secretary announced that ten members had taken part in the last North Wales trip. The Belfry Engineer agreed to investigate the leak in the kitchen roof and to suggest a scheme for ventilating the roof space so that the likelihood of dry rot would be reduced. Alfie was given permission to purchase timber to the value of £2 for use as shoring in the Cuthbert’s Culvert scheme.

Whitsun Coach Trip to Yorkshire.

After the very successful coach trip last year at Whitsun, it has been suggested that we repeat the process this year. The scheme is that, if enough members agree to take part, the club will run a coach to the Gaping Ghyll area, members making their own arrangements about camping, eating, caving, or any other pastime they may be thinking of. Anyone interested should get in touch with Bob Bagshaw or any committee member.

Articles.

Although we had a good stock, this is a twelve page B.B. and uses up a lot of material. More stuff will be very welcome. _______________________________________________________________________________________

Notice Film Show. There will be a film show at Redcliffe Hall on the 30th March. The main film will be "The Loving Spirit" _______________________________________________________________________________________

Personal Congratulations to ''Ronnie'' and ''Sage'' on the birth of their second son, Timothy John. He was born on February 11th and weighed ten pounds. _______________________________________________________________________________________ Answer to Last Month’s Problem ................................ 4½ gallons. _______________________________________________________________________________________ New members BACK NUMBERS of some of last year’s issues of the BELFRY BULLETIN are still available at the Belfry. Price 3d each. These are obtainable from Alfie or Sett.

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Number 157

CAVING

March 1961

LOG for 1961

January 1st, Eastwater. George Honey, Jim Giles and Mike Calvert. An interesting trip made to this cave in order to ascertain the condition of the boulder ruckle. This was found to be in the same condition as it always has been - rather loose. Some dressing down was done, but probably the best method would be force or shoring in the boulder Chamber as an alternative. A large black block hanging from the roof is the main hazard, the floor being covered with loose rocks. This part is certainly no more dangerous than it ever has been. A quick trip was made down the Dolphin Pot to the top of the thirty five foot pitch. The rest of the system is quite stable. Mr. Geeks (The farmer) asked us to contact the M.R.O. rep to ask for an early decision on the future of this cave.

January 5th. Brimble Pit & Thrupe Swallet. Mike Baker; George Pointing, Norman Tuck and Jim Giles.

Brimble Pit was inspected, also Thrupe Swallet. This latter is situated about two miles north of Croscombe and was first dug by M.N.R.C. in 1936 but was considered unsafe. A few years ago Norman had another go at it and shored up the loose stuff. The shaft is now about thirty feet deep at which point the stream is reached. The stream disappears through a hole which is partially blocked with scree. Apparently this has accumulated since the summer. If more interest were taken in this dig, another Cuthbert’s could well be the reward. Jim Giles.

January 8th. Emborough. Alfie, Jill and Jim Giles, Another. ''Probe around" trip to this interesting dig.

A few photographs taken (by direct lighting) and about "100 tons" of leaf mould removed from the attempted shaft which was all washed in again.

Jim Giles.

14th January. St. Cuthbert’s. Intended surveying trip. Party got soaked in entrance pitch, and because of the inadvisability of staying in a cave on the brink of flooding, we went on a quick tourist trip. Leader R. Stenner. Party Llew and Jim Hill.

14th January. Swildons. Dave Causer and Steve Wynne-Roberts went down at about mid-day to continue digging in Shatter Pot. Several feet of progress was made and the passage is still large when excavated. Surfaced at 8 pm. Rather more water down the pitches than when we went in. Dave Causer.

14th January. Goatchurch and Sidcot. Jim Giles, Ron Towns, Tiny Tierney and Dave Smith. A beginners trip including the Maze in Goatchurch and Purgatory in Sidcot. Jim Giles.

15th January. Swildons. Mike Calvert; Bruce Lynn, Ron Towns, John Tiny Tierney, Dave Smith and Mike Langley. Wandered round dry ways and up stream passages. Damned wet.

15th January. Priddy Green Swallet. Jim Giles and Jug Jones. Spent three hours removing cowsh and rocks from the tunnel at the present basement of the dig. Succeeded in enlarging the size of the tunnel both sideways and in height quite considerably. At the moment the work is quite easy. How about some more diggers?? Jim. 29th January. Goatchurch. Jim Giles, Mike Baker and Ron Thomas. A photographic (?) trip to Boulder Chamber. The bear seems to be hibernating and not even the dreaded side lighting would wake it! Jim. Jim. 5th February. Cox's Cave. Jug Jones, John Ransome and Pat. A 2/1 trip proving very enlightening. We learned that (a) A large tin of red ochre is to be found in a tiny niche in a passage loading to the left and that (b) The river running through this cave comes all the way from Snowdon.

5th February. Great Oone's Hole. A complete trip led by Jug. A bat was found near the entrance.

11th February. Lamb Leer. George Pointing, Dave, Paddy and Jim Giles. Photographic (without side lighting) to the Cave of Falling Waters. Met a party of M.N.R.C. tribesmen who put on the winch for us; exceeding the 30 mph limit. Jim Giles.

March 1961

Number 157

Page 3

11th February. G.B. Nigel, Bob Picknitt plus eleven. Party split into two groups and went their individual ways. Nigel’s party went up White Passage into the Rift Chamber and up Rhumba Alley. Nigel got stuck and decided that discretion was the better part of valour and retired gracefully. Then down the Loop and Oxbow to the bottom of the Gorge and a steady trip out. What Bob’s half of the party did is beyond comprehension. Nigel.

10th February. Swildons. A Friday evening trip round the top of Swildons by some members of E.M.I. Caving Club. The party consisted of 5 beginners and it is of note that the amount of sweat produced by a caver is proportional to the amount of activity and the amount of excess flesh. (I'm glad I'm thin) ''Prew" 12th February. Swildons. Trip to Shatter Pot on mad fool venture to get cave insects and make temperature and humidity readings. Party, M. Calvert and B. Lynn. Leader Roberts.

12th February. Fox's Hole. Alfie and Jill visited this hole on their way to lunch.

12th February. G.B. Garth, Jim Giles, Jug Jones, Tiny, Steve, Brian Griffiths, Pete Winter, John Roby, Bob Ball & Mike Bell. The mob was fallen in outside the Belfry and transported to G.B. repairing Garth's back wheel on the way. Ventured down to the sump, which was thought to be lower than normal. On the way back up, the party split. Garth’s party sat about smoking while Jim and six others tried Rhumba Alley.

Tiny was well and truly stuck for about fifteen minutes and Jug, who was following, took the hint and went back when Tiny broke free. The remaining five carried on as far as was possible and returned. This was a return to caving for Jug who last week went to Cox’s and did not get stuck in the entrance squeeze. Jim G. 18th February. Swildons. Jin Giles, Dick Dunster, Richard Roberts, Ron Towns, Steve and Mike. The trip was an epic of pre-planning. It was intended to be a super Paradise Regained and Trouble Series photographic trip with side lighting, grub and lots of other exciting treats but due to Sod's Law we only reached Shatter Pot. Two of the team were without Goon Suits and suffered for it.

Jim, Dick, Richard and Ron ventured into though Shatter Pot diggings and by the trial and error method, found the right hole. The S.M.C.C. must be congratulated on their work in this Swildons system. Their tunnels are a work of art!

For those who haven't been to this part of the Empire, the recent extension to Shatter Pot is very impressive and has some remarkable mud formations. It is estimated to be about 250 foot long and consists of a rift, larger perhaps than the Shatter Pot Rift. The floor is made up of mud and large boulders with a stream running across at the furthermost end. As to the way on, who knows? The stream is only a small one and the sides of the rift don't look very promising. Perhaps the floor holds a few secrets. Only time will tell.

There must have been a film show on at Sump 1 by the numbers of Sandhurst types we passed on our way out, or maybe they were going to the Channel Islands. Jim. 18th February. Swildons. B. Lynn and Mike Calvert. A bug hunting trip as far as the mud sump.

Stream moderate.

20th February. Swildons. Tourist trip to sump 1 with four Lockleaze schoolboys. Leader Roger Stenner.

A pleasant tourist trip with the water not too high.

25th February. Swildons. Part, Len Dawes, Alice Grimes, Sheila Paul, Wilf and Pat. A scientific trip, stream tracing using indicator impregnated cotton. The cotton was placed in the Dry Way above the Old Grotto; in the Black Hole Stream where it emerges this side of Sump 1 and in the main stream way just above this point. The results of this test will be known in about a week or a fortnight.

26th February. St. Cuthbert’s. Leader Frank Darbon. Party George Pointing and four Farnham chaps.

Trip to Dining Room and High Chamber with fun and games in the Rabbit Warren. A very good trip indeed.

George can still make the entrance rift!

26th February. St. Cuthbert’s. Leader Mike Baker. Party Jim Giles, Ron, Pat Irwin, Len Dawes and two Wessex (Farnham) types. Trip to September Series, via Main Chamber, Trafalgar Chamber and Strand.

Mainly photographic. Air very thin in the Strand.

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Number 157

March 1961

CAVE PHOTOGRAPHY

by J.A. Eatough (Dept of Medical Photography, University of Bristol, and John Attwood.)

Editor’s Note: - Older readers will remember the articles on cave photography published in the B.B. and written by "Pongo" Wallis. They will find this article a useful ‘up-to-date' addition to these earlier articles. Newer readers will find this article invaluable to start them off on sound lines in the fascinating subject of cave photography.

There is nothing particularly difficult about cave photography, but there are points to remember about problems which are not encountered in ‘above ground’ photography. The photographer has to supply and place all his own lights, to produce the effects he requires.

PART ONE - EQUIPMENT. Expensive equipment is not necessary to produce fine cave photographs. The main requirements are robustness - to tolerate being dragged over boulders, through mud and water, and through crawls and squeezes, and reliability - so that possibly long and arduous trips are not made in vain.

THE CAMERA. As in other types of photography, any camera can be used, but it is of advantage if the camera has a ' B' or 'T' setting. In spite of the total lack of what photographers today call "available light', a fast lens is not required, f4.5 being quite adequate. A flash synchronised shutter is not required, the 'open flash' technique being far superior.

The film size used is a matter for individual taste - the authors’ choice of camera being a 35mm camera with a wide angle lens (Ilford Advocate Series II) for colour, and a very old quarter plate field camera, with a variety of lenses, for black and white.

Except for one small point, the Ilford Advocate camera might have been designed as the ideal caving camera. It is very robust (one of ours has been dropped a considerable distance down a rock face). In addition, the hard enamel exterior finish is easily wiped free of mud and the mechanism is free from unnecessary ornamentation.

The camera is fitted with a good quality 35mm wide angle lens, focussing down to three feet, in a simple shutter with a ‘B’ setting. This ‘B’ position, incidentally, is the only one we use in cave photography.

One of our advocates has been improved by having the viewfinder replaced by an open frame finder which is easier to use than the original optical device,' but the frame is not essential. This camera would do equally well for black and white photography, but we prefer the ground glass screen focussing, especially for close ups, and the individual treatment that can be given to the cut film we use.

FILM Modern ultra-fast emulsions are not necessary. For best image quality a medium speed panchromatic emulsion is required, i.e. Ilford K.P.3 or F.P.3 or Kodak verichrome Pan or Plus X. In the case of colour photography, the recently introduced Kodak High Speed Ektachrome has no equal. This film is quite fast enough (We have lit the whole of the Cascade in St. Cuthbert’s with one medium sized bulb). Its image quality and colour rendering are good, and the latitude available is quite fantastic. As in the case of camera, so with colour films - all types have their devotees.

CAMERA ACCESSORIES. These should be kept to a minimum but four are essential. These are (1) A tripod, which should be rigid when erected and which should be incapable of being rendered useless when covered by mud.

(2) Lens hoods, which are useful in keeping dripping water off the lens. (3) A cable release which must have a time lock to enable flash photographs to be taken with the shutter set at 'B' and (4) Supplementary lenses and filters as required.

ILLUMINATION. On this subject, the authors have no doubt whatsoever that flash bulbs fired by a battery and capacitor circuit are the only light sources suitable for cave photography.

Electronic flash units tend to be bulky; fragile; of low power and high voltage and these volts are liable to go astray when the equipment gets wet. Of flash powder, nothing can be said in its favour as it gets wet easily and won't burn, and in addition it is extremely difficult to judge how much to use for a given flash factor - some form of prior weighing being essential. In addition, stale powder appears to cause a reddish colour bias on colour films. Smoke from flash powder can be of such quantity as to make many photographs "one off” jobs. Lastly one of us (J.E.) has seen several cases of very bad burns caused by flash powder. (Editor's note: and I have been totally blinded for about a minute by the wretched stuff). Similar remarks apply to magnesium ribbon.

March 1961

Number 157

Page 5

The method of illumination we strongly advocate is to use flash bulbs fired from a battery-capacitor flashgun. The bulbs are reasonably robust and reliable and the output is constant, making exposure determination easy. The now PF1B bulbs are very small and produce a tremendous amount of light. These bulbs are supplied in packets of five and flash factors given on the outside of the packets can be relied on to give a good exposure, even when the cave walls are dark and the rock is light absorbing.

The battery-capacitor flash gun can be easily and cheaply made, and can be very compact. One of the unit's used by the authors only occupies a pack about 4" x 2" x 1" and will fire up to three bulbs at a time!

In the circuit shown below, a test lamp has been incorporated and this is recommended as each bulb can be tested in turn before firing. The bulbs can be wired in series or in parallel and each system has its following. The authors use the parallel system as it enables each bulb to be tested individually and one bulb can be fired as easily as three, without the necessity of shorting out the unused bulb holders.

Wiring Diagram for Battery-Capacitor Flashgun.

O

O

Outlet 1

O

O

Outlet 2

O

O

Outlet 3

6 +

+

2

1

3 4

5

Components.

1) 2) 3) 4) 5) 6)

Ex-Govt Hand hold press button (For bulb firing) 22.5 or 30 volt deaf aid battery (e.g. Ever ready B105) Test Lamp 2.5v, 0.2amp or 0.04amp.

Press .Button as (l) Capacitor. 100 mfd, 50 Volt D.C. working (or 25v depending on battery voltage used.)

Resistor. 2,200 - 3,900 ohm Ÿ or ½ watt.

Voltage of capacitor should be slightly higher than the voltage of the battery used.

Minimum battery voltage should be 4 volts/bulb resistance value should be approx 100 times battery voltage IMPORTANT. THE POLARITY OF THE BATTERY AND CAPACITOR CONNECTIONS ARE VERY IMPORTANT. WRONG CONNECTION OF EITHER OF THESE COMPONENTS WILL RUIN THE CAPACITOR. Cost - The three major components can be bought for 6/- to 7/-.

EQUIPMENT TRANSPORTATION. The rough handling that the equipment is liable to get in the mud and wetness of caves, demand that the maximum protection possible is given to all photographic equipment.

American made ammunition boxes, though rather heavy, have proved ideal, and can easily be obtained.

These boxes are very strong and have useful handles to which shoulder straps can easily be fitted and, most important, they are waterproof. Our equipment has been taken through the sump in Stoke Lane Slocker perfectly satisfactorily, and even though filled with gear, the boxes floated up on the other side and were easily located.

(To be continued.)

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Number 157

March 1961

Late Entry to Caving Log. January 1961. Alfie and Jill inspected two interesting holes in Lamb Bottom. One, a cave in conglomerate, believed to be a rift which has become choked with earth etc, at the top and thus provides it with a roof. This hole is about 30' long, 6-7 foot wide and 6' high. On the opposite side of the valley, the same rift is open at the top and extends in for about thirty foot, looking at its inner extremity something like the Butter Tubs in Yorkshire. Nobody seems to know them except Balch, who mentions them in his books.

Since this space was going gash and there was nothing of the right length to fill it with, we have to announce that, with no expense spared, we are reproducing a picture of a typical stalactite column, as it would appear if photographed with the dreaded, side lighting.

GOUFFRE DE CORBEAUX

By John Ifold Last August I went to the Ariage area of the French Pyrenees to study Palaeolithic art. Whilst there, I was invited by the Speleological Society of Ariege to descend the Gouffre de Corbeaux at Gelat in the forest of Belesta this being one of the most impressive caves in the Belesta area. After driving some distance along the mountain tracks, we left our transport at a farm and walked about a mile through the forest to the cave.

From the top, it didn't seem a very impressive hole, but the French members of the party put over the side what seemed to me to be about a mile of lightweight ladder and the leader of the party then disappeared over the edge. I had the rather doubtful honour of being the next and after being looked on with scorn for attempting to tie my lifeline on with a bowline (they insisted on a double reef knot) I set off.

After climbing down about thirty foot, I was clear of the overhang and found myself hanging in space - in an enormous hole which I later learned is 201 metres in circumference and with sides dropping a sheer hundred metres. On reaching the bottom, we scrambled down the scree slope which was littered with the bones of sheep and cows which had apparently fallen over the edge in the past.

About five hundred yards further on, we went down another ladder pitch, this time only about fifty feet which was more like home. Since we were rather short of time, I wasn't able to see as much of the cave as I would have liked and we had to turn back. Standing at the bottom of the entrance hole – seeing the ladder fading to a thread three hundred feet above me, I wondered if I'd make it, for I'd never climbed three hundred feet of lightweight ladder all at once before. I managed it, and it was certainly worth the effort.

The Gouffre is in Jurassic limestone and was first descended by Martel in 1902. _______________________________________________________________________________________ The Belfry Bulletin for March 1961. Editor, S.J. Collins, 33, Richmond Terrace, Clifton, Bristol 8.

Secretary. R. J. Bagshaw, 699 Wells Road, Knowle, Bristol 4.

Postal Department. C.A. Marriott, 718, Muller Road, Eastville, Bristol.