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We sometimes imagine the editor of some new caving club journal putting a sheet of paper into his typewriter and, while he waits for inspirations to arrive, typing ‘Volume I, Number 1’ at the head of the paper.

Statistically speaking, the chances of his reaching g Volume II are not very good.  It is therefore with some degree of pride that we present this two hundredth issue of the B.B.  The B.B. has had its fair share of ups and downs in the past and, on two occasions at least, it would have not been surprising if its publication had ceased but somehow, in the general manner of the B.E.C., it seems to have survived in spite of circumstances.

The B.B. has been called a lot of things in its time, not all of them complimentary.  This, to some extent, may be due to its rather odd position amongst the Journals of Mendip.  It is not a completely serious Caving Journal – although from time to time it does publish articles which can stand comparison with anything that is produced elsewhere – an example of which appears in this issue.  It is not, on the other hand, simply a newsletter.  The present editor likes to think of it as a club magazine which, like the club it serves, does good work from time to time but does not take itself too seriously.

As far as the future is concerned however, 1965 will see some new innovations in the field of caving journals with the advent of nationally distributed properly printed ‘glossy’ magazines like the Speleologist.  Whilst welcoming this and other magazines of its type we feel that it would be a bad thing if the club journals were to decline into newsletters as a result.  To a great extent, this will depend on the relative amount of serious authorship which the club journals can still attract in the face of temptation to authors of better presentation and more widespread distribution which the national journals will be able to offer.  It thus becomes of some importance to the club to improve the layout and all round appearance of the B.B. and steps are being taken to effect this type of improvement.

It is hoped that, starting in the New Year, the B.B. will be produced by offset litho process which should result in a neater looking appearance, enabling drawings to be included with fine detail and headings etc. to be more evenly printed.  At a later stage in the year, it is hoped to be able to get the B.B. actually typeset and, in conjunction withy the use of a better grade of paper, this should result in a professional appearance

As mentioned in the recent A.G.M., all this will cost the club rather more than the present magazine, which is produced on a ‘shoestring’ budget, and it will be largely wasted unless articles of all types, but of a high standard, are forthcoming.  During the last few months, there has been a good steady flow of material for inclusion in the B.B.  Let us see whether, in 1965, we can improve both the appearance and the standard, and eventually the size, so that the chances of the B.B. reaching its Four Hundredth Edition are not impaired by us.

“Alfie”

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Don’t forget you may purchase B.E.C. CAVING REPORTS from Bryan Ellis.  He also has a number of surveys and other caving literature.  Why not get in touch with him and treat yourself to some interesting reading matter???

A.G.M. & Dinner

The 1964 Annual General Meeting of the B.E.C. opened at 2.45pm, there being over 50 members present. Dan Hassell was elected as Chairman unanimously.  The Chairman then called for the ballot papers and any members resolutions.  ‘Mo’ Marriott. ‘Spike’ Rees and Nigel Hallet were elected as tellers for the ballot.  The tellers retired to count the votes (presumably so that they could take their socks off and count up to twenty).  Meanwhile, the Chairman read the minutes of the 1963 A.G.M., which were accepted by the meeting.

The Hon. Secretary then gave his report.  There had been 31 new acceptances for membership during the year.  Thus intake of about 30 new members per annum was typical of the last few years, but as fewer members were leaving the club, the total membership was rising and now stood at 172.  The Dinner was being held in Bristol this year.  Members were sorry to hear of the deaths of two members during the year – Lionel Williams and Ian Dear.  Ian had left £150 and all his caving and climbing equipment to the club and had in addition left a further sum of £300 to assist junior members who wished to cave abroad.  The remaining point the Secretary wished to bring to the attention of members was that during the year, a National Caving Organisation has been suggested, but this suggestion is not acceptable to Mendip clubs, who are forming a body with the object of maintaining the status quo.  The adoption of the Secretary’s report was proposed by R.A. Setterington and seconded by Gordon Tilly.

The Hon. Treasurer then gave his report.  For some reason, the traditional pretence of surprise at finding this was the same bloke was absent this year.  He apologised for the incomplete nature of his financial statement but explained that £29 had been received from the Hut Warden too late for inclusion.  Receipts from Redcliffe and from membership fees have increase this year.  He reminded members that he had said last year that the expenditure of £5 on tackle was, in his opinion, too low.  However, £60 spent this year was probably too high to be continued at this rate (cries of ‘Stop-Go economy!’).  The Belfry Expenditure includes the cost of the water heater and the new mattresses but not the £29 receipts.  We now have paid our share of the C.C.C. legal expenses and the deficit on club ties means that a large stock now exists for people not wearing them.  To sum up, the clubs financial position is adequate and should be further improved when the legacy is received.

Oliver Lloyd asked how would the legacy be invested?  The Hon. Secretary replied that it would be invested in Savings Bonds.  Mike Luckwill asked how it was intended to be used.  The Chairman said this subject would be coming up later.  Gordon Tilly then proposed that the report be adopted and this was seconded by John Ransom and carried.

The Caving Secretary being still occupied with the counting of votes, the Climbing Secretary gave his report next.  Trips have been run as announced during the year in the B.B. and elsewhere.  These have been mainly to North Wales, but Cornwall and Dartmoor have also been visited and a fair amount of local climbing has also been carried out.  There have been quite a few requests for information but now many new recruits have been forthcoming.  There was no questions, and the adoption of the report was proposed b y Gordon Tilly (who could not in any case equal Mike Luckwill’s record for proposing reports at the A.G.M. since he will not be able to propose the acceptance of his own Hut Warden’s report later in the proceedings!) and seconded by Kangy King.

The Tackle Officer’s report followed.  He stated that this year, no tackle had been lost.  We are now the proud possessors of 410 feet of ladder and 780 feet of lifeline. We have 16 tethers, ranging from 18 inches to 27 feet and we should finish up, when the present ladder building programme is completed, with 630 feet of ladder.  Dave Irwin asked whether the expenditure quoted by the Hon. Treas. Covered all the remaining ladder. The Tackle Officer said that it did all except the wire.  A vote of thanks was recorded to the Tackle Officer for his work in producing so much tackle.  The adoption of the report was proposed by Mike Luckwill and seconded by Gordon Tilly and carried.

The Editor of the B.B. then gave his report.  Since most of what he said is in the forward to the issue of this B.B., it will be omitted here.  John ransom proposed the report be adopted.  This was seconded by Gordon Tilly and carried.

The Hut warden announced that bed nights were again very high and stood at approximately 1800.  Very few breakages had occurred at the Belfry. The hot water system has gone a long way towards dealing with the washing up situation, but has proved expensive to run.  He suggested that it was enough for the time being.  The Hut Warden concluded his report by saying that he would like to express his thanks to club members for their co-operation and particularly to Sett and Jan.  Kangy asked why the hot water system was held to be expensive.  He wondered if Gordon could enlarge on this point.  Gordon replied ‘not particularly’.  Some discussion on the cost followed.  Alan asked if this year’s committee could do an analysis of the cost.  The Chairman suggested that this be left to the Committee to decide whether they considered this to be necessary.  Alan Thomas asked if the heat from the Belfry Stove could be utilised in some way. Alfie thought that this was not really practicable.  Frank Darbon then proposed that the report be adopted.  This was seconded by Alan Thomas and carried.

The Hon. Sec. then read a note from Bryan Ellis who stated that no Caving Reports had been published during the year, but that the sales of the previously published reports continue. A balance amounting to £4.17.8 is in hand towards the cost of publishing a further manuscript.  Alan Thomas asked whether anyone knew if a further manuscript was in the course of preparation.  Alfie replied that he thought one was being prepared by Dave Irwin on the Long Chamber area of St. Cuthbert’s.  This was confirmed by the author. The Chairman suggested that continued publicity be given to the sale of caving Reports in the B.B.  This was noted by the editor.

The Hon. Librarian’s Report followed.  Borrowing was sporadic amongst the older members but continues amongst the younger members.  There had been some 114 borrowings during the year.  Ian left the library all his books and surveys and maps of caving areas.  As a result we have new maps of all the caving areas in Great Britain.  The library copies of the B.B. were being bound.  There were no questions and Alfie proposed that the report be adopted. This was seconded by Frank Darbon and carried.

The Belfry Engineer then gave his report.  A coal and coke bin had been made in the Belfry and two large lockers which were big enough to take rucksacks.  The leaks have been repaired in the roof.  A urinal had been built out at the back.  The Belfry had been creosoted, the ceiling had been done, the asbestos panel for the chimney is being fitted and the car park extended.  There were no questions and Gordon Tilly therefore moved that the report be adopted.  This was seconded by Sett and carried.

At this stage the result of the ballot became known and was read out by the Chairman.  Voting was as follows: -

Total number of members voting…87.  Votes cast for Bob Bagshaw (79); Norman Petty (78); Roy Bennett (75); Alfie (74); Alan Thomas (65); Kevin Abbey (64); Dave Irwin (63); Gordon Tilly (53); Keith Franklin (47); Mike Palmer (44); Sett (43); John Ransom (38); Phil Kingston (20). The Committee therefore consists of Bob Bagshaw, Norman Petty, Roy Bennett, Alfie, Alan Thomas, Kevin Abbey, Dave Irwin, Gordon Tilly, and Keith Franklin

After an adjournment for light (non-alcoholic) refreshments, the Caving Secretary gave his report.  He said that the general level of caving had shown an increase, with Cuthbert’s overshadowing all other caves in popularity. There had been no major discoveries outside Cuthbert’s.  However, activity was increasing in digging projects.  Castle Farm Swallet was being energetically pursued, also Hunters Hole. B.E.C. members has also been active in work on the S.E. Inlet Series in Swildons.  The level of co-operation amongst cavers was good, but there was some room for improvement.  A practice Rescue had been held in Cuthbert’s.  The New Entrance was now in full commission and the Old Entrance had been filled in.  He concluded with a plea for some serious scientific studies in Cuthbert’s. Questioning the Caving Secretary, Roger Stenner asked why the work on new caves in South Wales had not been included?  The Caving Secretary said that he thought this work had occurred last year, and asked whether more recent work had been written up in the log.  Gordon Tilly proposed that the report be adopted and this was seconded by Alan and carried.  A vote of thanks to the Caving Secretary was proposed by Kangy King and carried.

Under ‘Members Resolutions’, Alfie proposed that “No person under sixteen may stay at the Belfry without the previous consent of the Hut Warden and the presence of Parent or Guardian”. This was seconded by Gaff and carried (38 for, 3 Against)

A resolution ‘that every effort again be made to install the new shower system within the next six months’ was proposed by Jill Tuck and seconded by Alfie.  Alan Thomas reported that work was in hand but was being delayed at present due to a general shortage of copper pipe.  The motion was carried nem. com.

A further resolution by Jill Tuck ‘that more blankets be acquired for the Belfry’ was seconded by Roger Stenner and defeated (1 for, 38 against).

Another resolution by Jill Tuck ‘ that a new telephone line be laid out on Cuthbert’s’ was discussed and an amendment was proposed by ‘Mo’ in view of the technical possibilities ‘that a communications system be installed in St. Cuthbert’s’  The amendment was seconded by Alfie and the amended resolution was carried unanimously.

The meeting went on to discuss the terms of Ian’s bequest. Since this will be the subject of a separate announcement, it is omitted from these notes.  There being no further business the Chairman declared the meeting closed.

The Annual General Meeting was followed by the Annual Dinner which was held for a change this year in Fairfax House, and the Co-op Headquarters, in Bristol.  Whether the choice of venue was due to the B.E.C. uncanny knack of anticipating the next government is not clear but, at any rate, those who feared that they might have to drink Wheatsheaf beer were soon put at their ease.  It is reported that the actual meal (which the writer personally regards merely as serving the function of blotting paper at these functions) was not adequate for some of our growing lads!  The general feeling seems to have been that it was not bad, but should have been better for the extra money.

The speeches went off well, Alan Thomas’ new gimmick this year being the use of a tape recorder to enable ‘absent friends’ to reply in person.  Unfortunately the volume was not as high as the size of the gathering warranted. The speeches (including the presentation of a useful present to Kevin Abbey) were followed by one of Kangy’s floor shows.  This time it took the form of a pageant of ‘Caving through the Ages’.  This commenced with a wonderful spectacle of Barry Wilton as Homo Speleogenesis – and Early Homo, who demonstrated the origin of ‘painting by numbers.’  Next we saw Frank as a Celtic Caver (complete with A.O.I.F.L. which he waved triumphantly). This was followed by an Elizabethan Caver – portrayed by Keith Franklin and showed us Sir Fancy Cake nonchalantly playing shove ha’penny while the Wessex were invading Cuthbert’s.  Having won his game, he then pulled the plug out of the dam and drowned them.  This was followed by a Victorian Caver in the person of Gaff Fowler – engaged in robbing caves of stal. and oppressing the working classes (played by Roy Bennett). Finally, we had a glimpse into the future and saw a Super Caver in a topless wet suit.  Keith Franklin played this part as well as the City Gent Type Caver who followed.  I have, of course, missed out the touching scene which came between the Victorian Caver in which Balch meets Martel in Celtic embrace.

More drinking followed this pageant when another series of interludes occurred.  Oliver Lloyd was persuaded to sing his trilogy of Swildons songs; a man recited a poem and a slightly shambolic singing act took place. A static exhibition featured various aspects of club activities.  Displays of caving and climbing photographs; recent progress in St. Cuthbert’s; Castle Farm Dig; the B.B.; Caving Gear and a collection of finds in cave quarries were arranged round the walls of the room.  The dinner appeared to have been a success – at least, not many grumbles have been heard to date!

Note:    This account of the A.G.M. and Dinner is not an ‘official’ one or guaranteed free from mistakes.

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R.J. Bagshaw.            Hon. Secretary and Treasurer.
N. Petty.                    Tackle Officer
Roy Bennett.              Climbing Secretary & B.B. Postal Department.
Alfie.                          Committee Chairman and Hon. Editor, B.B.
Alan Thomas.             Belfry Engineer.    Kevin Abbey.  Assistant Caving Secretary.
Dave Irwin.                  Caving Secretary and Minutes Secretary.
Gordon Tilly.               Hut Warden.
Keith Franklin.            Assistant Caving Secretary.
Joan Bennett.             Hon, Librarian.

State of the parties. Caving Secretaries Party 3, Independents 6.

The Sequence of Development of St. Cuthbert’s Swallet – Part 1

by Derek Ford.

This account is written for fellow members of the Bristol Exploration club in the hope that it may help them to enjoy their favourite cave even more.  It is based on a study made there during the summers of 1960 and 1961. This was aimed at determining the mode and sequence of development down below, which was then compared to similar studies made of Swildons Hole; G.B. Cave; the Gough’s group of caves at Cheddar, and Wookey Hole.

In many respects St. Cuthbert’s proved to be the most complex and interesting of these caves. This is partly because it is the oldest (the sequence for events at G.B., for example, is much shorter) and partly because, in the past, it drew its water from an unusually large surface basin with a varied assemblage of rocks.  Today the cave drains something less than half a square mile of the adjacent parts of Stock Hill and North hill, but in former times, its took water from well north of the Miners Arms via Stock Hill – North Hill Valley.

This narrative gives a sequential description of the creation of modern scenery in the cave. It omits almost all the evidence, for the sake of brevity.  When typed out with the evidence my account of the cave ran to over 200 pages, supported by some 30 diagrams.  St. Cuthbert’s is really quite a place.

Its history is divided into phases and sub-phases, distinguished by greater or lesser changes in the prevailing dynamic conditions.  These phases are can be grouped into three major stages of development: Phreatic Erosion, Vadose Infill and Vadose Re-excavation.

MORPHOLOGICAL SUB-DIVISIONS OF THE CAVE

For the purpose of this description, the cave may be divided into four areas having distinctly different forms.

First is a central complex of partially collapsed chambers, extending to form Long Chamber and Coral Chamber in the west, to the September Chambers in the east.  These chambers rest on, or close to, the base of the limestone which are here lying on shaly transitional strata sloping at about 38 degrees to the S.S.E.  The chambers follow the bedding planes and several systems of joint and fault fractures, which coalesce in this area – creating a very tangled structure.

Second is the Gour Rift.  This is the biggest passage in the cave, following a major vertical, fault. The original Gour Rift of the explorers is only the South Eastern end of it.  To the North West, Cerberus Hall, Mud Ball Chamber and Lake Chamber are further accessible parts – separated from each other by places where stream laid fill and stalagmite reaches the roof.

Third is the Warren area.  This includes all the passages between the central complex and Gour Rift – Everest Passage; the Fingers; The Rabbit Warren; The Railway Tunnel; Main Stream Passage; The Warren Extension and The Tin Mine.  All are comparatively small and were developed to convey water from the big chambers to the north, to the rift passage.

Fourth are a series of comparatively recent inlet passages which developed to feed the Central Complex or underneath it long after it had been expanded by water from other sources.  The inlets are the Arête Route,  Pulpit and Lower Traverse Chamber Route, Maypole Series and High Chamber.

SEQUENCE OF DEVELOPMENT

The Phreatic Expansion.  About two thirds of the volume of the known cave can be attributed to solution under phreatic conditions (complete water fill beneath a water table surface) or to collapse which followed immediately after that fill was drained.  There are two distinct phases of phreatic expansion

(a) Phreatic Bore Passage Phase.  In this phase, water entered the known cave through Rocky Boulder Series and the collapsed area at the N.W. corner of Upper Traverse Chamber. The contemporary water table was at, or above 660 feet O.D.  A series of long narrow rift chambers was opened below it, between Coral Chamber and Upper Traverse Chamber.  They were drained into Gour Rift by a remarkable system; the Warren “bore passages”.  By this trem, I mean a very efficient conduit, with minimum wall friction and little or no wastage of the solvent power of the water eroding large blind alleys.  The Warren bores were very efficient, being nearly circular in cross-section (a circular pipe has least friction) and following fairly direct linear courses.  There were four principle bores, all converging to flow to the E.S.E. and arranged in a tier – the highest to the north.  The highest drained the southern end of Upper Traverse Chamber and may be followed east from the junction of that chamber and Harem Passage, to a stalagmite choke.  The second was the Railway Tunnel draining an early rift in the area of the Cascade and the southeast part of Boulder Chamber.  It spilled some water south (down dip) through lesser bore passages. Due to this loss of water, the dimensions of the Tunnel are progressively reduced.  The third bore was much the smallest.  It ran from Everest Passage, through the Fingers and the centre of the Warren, to the top of the Sewer and Plantation Junction.  It received many tributaries from Tunnel Passage and distributed water to the fourth bore.  The latter is the oldest part of the Main Stream Passage.  It began at the head of Everest Passage, drawing water from the precursors of Everest Boulder and Curtain Chambers, spilled a little into the Rat Run and then meandered E.S.E. to turn into its discharge – the Great Rift – at the Dining room.  Here the roof of the rift (Cerberus Hall) is exceptionally high, being driven upwards by the erosive power of waters delivered into its base with some force. These waters then moved S.E. towards the present termination of the cave.

The three higher bores all fed into Plantation Junction.  East of their terminal chokes, the Upper Traverse and Tunnel bores (the two largest) split into a series if distributaries, which can be seen, almost entirely choked with stalagmite, crossing the extension passage at its floor level.  Beyond it, they turned south, developing the choked passage which the Plantation Stream follows today and reaching the junction at some place beneath the great sand and stalagmite bank there.  From the junction, the water cut a fine elliptical bore passage straight to Beehive Chamber, where it turned steeply upwards (Pyrolusite Series) to enter the Gour Rift more or less directly above the highest gours.  The modern route from Beehive Chamber to the rift is a subsequent bore passage, also climbing up to its outlet.  As at Cerberus Hall, the roof of Gour Rift is highest over these points of input.

The dimensions of individual bore passages remain nearly constant between tributaries or distributaries. Thus, making some assumptions, it is possible to calculate the velocities of the formative flow through them. Velocities are very low, despite the efficient flow cross sections of the passages.  The picture is one of water moving slowly through a mesh of pipes from one system of semi-static reservoirs (the central complex) to another (the Gour Rift).  Correspondingly, the water table was exceptionally flat and stable and the time taken to expand the cave thus far was possible as long as all its later phases combined.

(b) Phreatic Disintegration Phase.  A change in the dynamics of flow, or chemistry, of the groundwater then tore much of the efficient mesh of bore passage apart and greatly increased the volume of the cave.  The water table remained at 600 feet.  Most of the bore passages developed into bedding planes, the line of the plane bisecting the tube.  Disintegration took the form of a wide expansion along the plane, on one or both sides of the tube.  Often the lower half of the tube was destroyed altogether.  This can best be seen along the direct traverse from The Fingers to the Sewer.  Most of the Sewer Passage is a result of this phase.  So is the manner in which the south wall of the extant Railway Tunnel is torn out along the guiding plane.  To the west, the roof of the tunnel can be traced curving up a great joint surface over the foot of the Cascade.  The floor here was entirely dissolved away.

There was much expansion in size of the Central Complex.  The most important development was a direct connection between the complex and the rift, short circuiting the old flow lines, through Long Chamber and Curtain Chamber, joining the Rift at roof level at the choked point between Lake and Mud Ball Chambers.  Theses two chambers are largely a product of the phase.

A new phreatic stream from an independent sink entered the system during this phase.  It opened up September Series and thus impinged on the Eastern end of the bore passage mesh.  This was overloaded as a result and the extension passages below Cross Legs Squeeze were developed as remarkable sub-water table overflow channels. In many parts it will be found that their course is not controlled by any notable fractures at all.

(c)  The fall of the Water Table.  At the end of the second phase, the water table fell from above 660 feet to a little below its present level of 380 feet O.D.  The rate of fall was slow at first but there were no prolonged stands above 380 feet.  The vertical amplitude of the drop – at least 200 feet – is greater than any detected in the other central Mendip caves that I have studied and requires explanation.

Fall of the water table in a Mendip inlet cave, such as St. Cuthbert’s is caused by a fall of roughly equal proportions at the outlet.  In simplest terms, falls at the outlet caves such as Wookey and Cheddar, can be attributed to falls in the level of a past sea filling the Somerset Moors to the south. There have been several such falls from maximum level above 500 feet O.D.  The vertical amplitude of each fall was around 100 feet or less.  Swildons Hole is a complicated cave to explore because it has developed new systems of passages in response to each of the four major falls of the water table transmitted to it by the outlet.

St. Cuthbert’s shows only one fall, its amplitude as big as the aggregate of the four in Swildons Hole. This is because its outlet lies amidst an unusual geological complexity, called the “Ebbor Thrust Zone.”  (F.R.A. Welch, 1929.  Quarterly Journal of the Geological Society of London, Page 45).  During the phreatic phases, St. Cuthbert’s discharged its water through caves in Ebbor Gorge.  Cave remnants can be seen at the steepest point there (Bridged Pot Shelter, &c). The level of the discharge was above 500 feet.  It was held at this height by a block of impermeable rocks, quartistic sandstones of millstone grit (lower coal measure age) infaulted across the mouth of the gorge. These functioned as a subterranean dam and held the water up at Ebbor Gorge during the several falls of sea level on the downstream side.  Finally, when the sea level stood at somewhere around 240 feet O.D., the pressure effected by the groundwater held above 500 feet caused a leak to develop around the side of the dam.  Wookey Hole is the downstream end of this underground leak.  The breakout at Wookey drained St. Cuthbert’s via the present terminal stream passage.  During the phreatic phases the water probably left Gour Rift via its impassable narrow southern extension and/or avens in the roof close by.

When the water table fist began to fall in the cave, a new swallet developed at the surface, close to the modern entrance.  Once underground, its stream bifurcated.  The larger part opened the Arête and Wire Rift Passages, though not to their modern dimensions, whilst the smaller passed into Maypole Series, joining the accessible passage there at the highest right hand bend (going upstream).  A tall but very narrow rift was opened, the great potholes being later features.

Three gravitational streams now ran into the Central Complex.  One of these (Rocky Boulders and Wire Rift Water) flowed through Boulder Chamber into the head of Everest Passage where it undermined the phreatic honeycomb of the disintegration phase, causing a great deal of collapse, which remains as the base of a long sequence of deposits.

The second of these streams (Northwest corner of Upper Traverse Chamber and Wire Rift) flowed into Cascade Chamber and through The Fingers to join the first.  It too caused collapse all along its route.  The combined stream entrenched the floor of the lowest bore passage (Main Stream Passage) but did not follow its old route through the Dining room into the Rift.  Instead, the flow broke laterally into the Sewer.  This lay at lower elevation, causing a waterfall and the abandoned plunge pool which is now Stalagmite Pitch.  There was also entrenchment between Plantation Junction and Gour Rift. At the cavers entrance to the rift it is twenty feet deep and thoroughly choked with later stalagmite.  The third stream (September Series) precipitated much of the collapse there.  Rock fall has been so heavy in this part of the cave that little detail can be distinguished.

2. The Main Fill Period.  The rest of the history of the cave is a sequence of alternating phases of erosion and various kinds of deposition by gravitational waters. During the first half, deposition predominated and the cave was pretty thoroughly plugged up to 640feet O.D. This period may be called the “Main Fill.”  It had many phases and sub-phases.

In the central and south eastern parts of the cave, the first phase alone was significant.  Fast streams from Boulder Chamber and Upper Traverse Chamber plugged the terminal stream passage with an assorted mixture of silt, sand, pebbles and good sized stones.  Much of the material comes from erosion of the north side of Stock Hill and places further north.  It filled back to Plantation Junction and then choked the entire Warren, Everest and Main Stream Passage areas. Much of it can still be seen.  For instance it composes most of the west wall of Everest Passage: a few feet below Plantation Junction, remains are jammed in the roof, eighteen feet overhead.

The filling of this phase stopped when the accessible parts of the Railway Tunnel were about a third full. Two later phases of coarse stream deposition can be recognised in the remains preserved along the north wall there. The central deposit has a few of the larger stone sizes (cobbles) which distinguishes it from these above and below. At the close of the third phase, the further parts of the Tunnel were fully choked also.

The streams thus clogged their first vadose route to Gour Rift.  As a result, they were spilled through the abandoned phreatic short circuits into Lake and Mud Ball Chambers.  From here to the S.E. the floor gradient of the rift was evidently much lower than gradients elsewhere in the cave.  This permitted sequences of gradation deposits to be laid upon it.  The long series of phases and sub-phases of the main fill is largely derived from analysis and correlation of two exposures of the rift fill.  One is seen in the S.E. corner of Mud Ball Hall, the other is the climb up from the Dining Room to Cerberus Hall.  These two sections are more complex than any others that have yet been described at sites deep within British Caves.

Rhythm is characteristic of their sequence.  Any one phase begins with the deposition of the unsorted, coarse stream fill described above.  Then follows a layer of small pebbles and sand, indicating a reduction of rate of flow of the steam and, almost certainly, its volume.  The next is finer still, of sand and clay only and this is followed by a layer of stalagmite.

Stalagmite sub-phases are common throughout the vadose history of the cave.  The evidence is quite clear that, when they occurred, there was no proper stream flow in the cave.  The only water underground was that permeating tiny cracks, becoming saturated with solutes in them and so depositing calcite when it reached larger cave spaces.  It must not be supposed that calcite deposition by permeating waters goes on continuously in an air-filled Mendip cave, spilling into the big stream channels if these are temporarily abandoned by their erosive waters.  Small forms may be continuous but otherwise the record is again clear, in all of the caves mentioned.  Periods of vigorous stream flow are periods when the permeating waters erode away the formations that they have earlier deposited.

The depositional phase described is thus one of progressively reduced stream flow, terminating in a cessation of flow and general stalagmite deposition.  The next phase may begin with some vigorous erosion of the stalagmite by a renewed stream.  Coarse deposits follow before there has been much clearance; then a reduction of flow, with sand deposition, and so on.  In the western half of the rift, the record shows five of these gradational phases, the first correlating with that which plugged up the Warren.  The last is incomplete, being halted when the fill reached the low roof between Mud Ball Chamber and Cerberus Hall.  It may be presumed that there were further depositional phases in the higher parts of the cave, but no certain evidence is preserved.  At its peak, the main fill extend to choke up most of Wire Rift (remains can be seen in two high false floors there).  There can have been little open cave below.

The Extension Passage was choked.  First by fill carried down the Warren Passage which crosses it, then by the September Stream itself.  The original phreatic passage (Continuation Chamber to Plantation junction) remains largely choked with coarse fill.  In Extension Passage, the most striking feature of the fill is the great depth of stalagmite layers.  The best section can be inspected at the entrance to Helictite Passage.  A stalagmite floor there is 36 inches thick; it rests on coarse fill burying an earlier stalagmite.  The floor was deeply entrenched on the west side by a stream which then filled up to the top of the extant passage (Cross Legs Squeeze). Continuation Chamber was also quite choked.  A good stratigraphic section is exposed at the climb down into it.

No other Central Mendip cave has been so clogged with stream as St. Cuthbert’s.  This is because it had a much larger catchment basin during the Main Fill times, including a great deal of easily erodible Mesozoic rocks.

(To be concluded in the CHRISTMAS edition of the B.B.)

Editors Note:     lthough it goes against the grain to have to cut the main article of this B.B., its total length is such that it cannot at the moment be included in a single B.B. without some production difficulties.

Caving Log

….for August and September.

Edited by Barry Lane

On the 3rd August, another incident occurred in Swildons whereby a party was trapped because of the absence of ladders.  Fortunately, the “rescue” was only a case of Noel McSharry and Alan Thomas taking ladders to the top of the pitch.

On August 15, digging tools were brought out of the S.E. Inlet Dig in Swildons by Alan Coase, Barry Lane and Chris Harvey.  The dig has been has now been abandoned since a recent breakthrough revealed 15 feet of passage which closes down to ‘an almost impossible choke’.

Dave Irwin was “at home” in the Marble Hall area of St. Cuthbert’s on the 22nd, with Mike Luckwill and Phil Kingston.  A choke was pushed at the south end of Coral Chamber, to a 50 foot pot which was choked at the bottom.  Stones were dropped through holes in the choke and travelled a fair way.  A further look at Marble Hall revealed a boulder ruckle with a very large passage leading off.

On a trip to Trat’s Temple on the 28th, Chris Harvey climbed to a hole high up in the stream way, but unfortunately slipped.  He did not describe the hole when writing up his trip in the Caving Log!

Tony Meadon and Mike Luckwill investigated the sump at the bottom of Cone Chamber on 28th, which has earlier been reported dry. Digging commenced with bare hands and the length of the passage increased by six feet, revealing a promising dig.

Roger Stenner went down St. Cuthbert’s on September 2nd to examine some of Don Coase’s surveying gear, and brought out his tripod for cleaning.  Roger also requests leaders to ensure that old surveying stations have not moved or tampered with, as the new surveys will not make them obsolete. They will also be of great value when other people’s surveys are tied in.

On the 15th, Alan Thomas and Dave Irwin removed some of the fill from the bottom of the 50’ pot mentioned earlier, which is near Marble Hall.  Alan had some trouble climbing out which, at the top, is reported to be ‘extremely interesting’.

On the 18th, these same two pushed a passage into a chamber above Long Chamber Extension.  A way on can be seen but needs some enlarging.  A fine set of curtains were noted, also an erratic which grows upwards in the stal. floor.  On the very next day, the passage was again pushed by Geoff Bull, Tommy Thomas, Pete Hudson and guess who?, but was found to close down after about sixty feet.

On the 25th of September, Alan Thomas and Dave Irwin inspected a hole in the roof of Pillar Chamber, near the three runged ladder.  They followed a passage or forty feet into a reasonably sized chamber which was immediately above the chamber at the top of Rocky Boulder Passage. Several other holes were noted on route. A hole in the roof of this chamber led to an even larger chamber with a vertical rift on the left hand wall. This rift is apparently very well decorated.  A bedding plane at the lower end of this chamber seems to have possibilities of connecting with a bedding plane off Long Chamber.

The Belfry Needs You Too!

What an excellent thing it would be if we had some tools at the Belfry.  If every member of the club presented one tool, this would make a nucleus of over 170 tools which could be used to improve and maintain the Belfry. Have YOU an old tool you could give the club?  Perhaps your tool is old and worn; perhaps it is bent or misshapen; perhaps you do not know what it is for or you have grown tired of it.  Perhaps you have two.  Whatever its condition we should very much like to receive it.  Tools of every description come in useful.  Tools donated will be kept under lock and key by the Belfry Engineer so that they last.  A list of all tools and their donors will be published in due course – sharpen chisels, reset saws etc.  Please respond to this appeal if you can!

Mendip – Sixty Years Ago

by Alan Bonner.

I recently bought a set of bound copies of ‘The Climbers Club Journal’ for the years 1898 – 1904, and, under the heading “Kyndwr Club Notes” found the following report which I hope will be of interest to the caving members.

At the close of 1902, two members, Baker and Bamforth, accompanied by Mr.  Morland and Dr. Sheldon, went into eight caverns in the neighbourhood of Burrington and Cheddar in Somerset.  They attained a number of points that had never been reached before and secured an interesting series of photographs.  A great deal of work remains to be done at these two spots. Later on Baker and Bamforth joined a party led by Mr. H.E. Balch of Wells – a most persevering speleologist - who has put into practice some ideas of his own with excellent results.  His speciality is excavation.  At Eastwater, on the top of Mendip, he sunk a shaft into a swallet and so discovered a great cavern, through which a stream flows on its way to the water caverns of Wookey Hole.  On the occasion referred to, a party of nine penetrated to a depth of more than six hundred feet below the surface, and to a distance of two thousand feet from the cave mouth.  The cave is exceptionally difficult.  Its passages are so narrow as to be almost impracticable, the explorers having, to give just one instance, to crawl through an S-bend with a diameter of nine and a half inches.  There are awkward vertical drops, with deep pots lying in wait beneath them; long craggy canyons across slopes of 500 and –worst of all – enormous accumulations of jagged rocks, through the midst of which it is necessary to crawl and wriggle, carrying quantities of ropes and other apparatus.  Though it proved that the Eastwater Cavern drains in to Wookey Hole, all attempts have so far proved unavailing to explore the canals and water pipes that lie between.

At Wookey Hole, the upper galleries as well as the water caverns were explored, with a view to finding the connecting links and since the Kyndwr man left, Mr. Balch has cut a way into a new cavern of almost unparalleled loveliness, which promises to lead on into the unknown region between the two series of caverns.

The report goes on to mention the Cheddar Caves and Lamb Leer and ends: - ‘There is a lot of cave work to be done in Somerset and many promising caves have hardly been touched.’

The Kyndwr Club appears to have been formed in Derby in 1900 or a little earlier and, from the reports in the Journal referred to, were very active in the caving and climbing fields.

Sett’s Mathematical Puzzles.

Pending an answer to the last problem, which will appear in next month’s B.B., you may like to try this “quickie”.

One year, Ben decided to count the total number of pints he served at the Hunters to cavers, so he kept a tally.  On totting up the final figure for the year, he noticed that it ended with a 4 and that, if he moved this 4 to the other end of the number, the new number thus produced was exactly 4 times as big as the one he had got.  What was the number?