The Bristol Exploration Club, The Belfry, Wells Road, Priddy, Wells, Somerset.
Editor: John Williams 

1996 - 1997 Committee

Hon. Sec.                Nigel Taylor
Treasurer                 Chris Smart
Caving Sec.             Jeff Price
Hut Warden             Becca Campbell
Tackle Master          Mike Wilson
Hut Engineer            Ivan Sandford
Membership Sec.     Richard Stephens
B.B. Editor               John Williams
Librarian                  Alex Gee
Floating                   Hilary Wilson
                               Estelle Sandford


 

Editorial

So .... here is a rush release BB for you all. Some of you will have only just received the previous two issues, for this I apologise as there have been problems with the distribution which, touch wood, are now sorted out.

I have had various problems this year but will be able to keep to if not better my intended target of 4 issues as minuted at the AGM last year.  What would be nice is some help from people instead of the constant criticism and hindrance that I am coming across with monotonous regularity.

Publishing the BB is a very time consuming excessive ... as next years editor will no doubt discover. This is made no easier by members sitting on articles as I know some are doing.  Even less helpful is the backbiting that's been going on.

Well I can put you out of your misery by announcing that I don't wish to continue as Editor next year.. .. Full details will be in my end of year report and I will see to it that there is at least one more BB this year even if I have to write the whole thing myself.

The people I am referring to here know who they are .... a shame the majority of membership doesn’t…my message is simple…..grow up!!!   Enough said.

There are plans for a tidying up / working weekend in the early part of August details to be confirmed at the next committee meeting.  The shed and general area are in need of some care and attention to say the least so all help will be appreciated.  I daresay there may be a pig roast or piss-up of some kind afterwards.

Its been fairly quiet at the Belfry recently and I understand that bed nights are down so the Club could do with the presence of some of you .... be nice to see some faces we haven't for a while anyway.

Lastly, sadly for those that don't know Rob Palmer passed away as the result of a diving accident recently.  Although not a BEC member Rob was known to many of us and had often visited the Belfry over the years.

Our condolences go out to his family.  See also article within.

That's it for now as I have to run to the printers now ...

Take it easy ...... Jingles.


 

From the Belfry Table

An Apology

I start with a full and unreserved  apology to David IRWIN.

In my last BELFRY TABLE article I sought to give publicity as requested by Dave IRWIN, to a new Mendip Cave Bibliography.

In error, I misinformed the readership by stating that the work was being published by Dave IRWIN.  From our conversation, I cannot explain how I came to assume, that as he was a major contributor to the work, he was indeed the Publisher, a title which I meant purely as a loose description to publicise the work in the space available in my article.  David has telephoned me recently and strongly pointed out my error and advises that the work is published by "The Mendip Registry", and it is to these persons that I also apologise for giving the credit to the wrong person. I am sorry for the distress.  David has apparently suffered, and did not realize the sensitivity attached to this issue.

Nominations For The 1997-1998 Committee:-

As Secretary, I now formally call for nominations in writing for candidates for the election of the 1997-1998 BEC Committee, for the AGM on Saturday 4th. October.

Nominations must be in writing, and be seconded by another BEC Member.  Only paid-up members are eligible, and to make it clear as I have often been asked, probationary members are eligible to stand.   Nominations must be received by the Secretary by Friday 5th September.  (Also this is the date of the Sept. Committee meeting).  To both comply with the Constitution and enable me to organise and circulate any ballot papers if an election is required. [Canst:5bl]

 (Jeff PRICE our Caving Secretary is the only member standing down, and all the remaining members automatically are re-nominated to stand again).

AGM & ANNUAL DINNER, Saturday 4th. October 1997:-

The AGM as always is set for 10.30 am at the BELFRY.   PLEASE TRY TO ATTEND THIS YEAR, WE DON'T WANT ANOTHER AGM LIKE LAST YEAR!!!!!!

The DINNER this year will be held at Bristol University Vet School, Langford House, Langford.  Just a short hop from Burrington Coombe for those of you who are lost off the Hill!  Details to be published later, or speak to me.

FIVE BUDDLES DIG:

Congratulations yet again to Jay-Rat and his team, now well across the road and under the Forestry at Five BuddIes, Well Done!

WHITE PIT:

At time of writing, White Pit is about to go again albeit foul air is causing a major problem to the small band of diggers.  There is some talk on the hill that the increased use of P.E.T.N cords being responsible [See article}.

THE COMPLETE CAVING MANUAL:

Andrew Sparrow is to be congratulated for his professional and most excellent latest work. Published by the Crowood Press Ltd, and written by Andrew this valued book runs to 192 pages.  He obviously has put much work and great effort into this volume, and its contents start with 'The Formation of Caves' through the varied subjects of getting started and trip preparation, equipment, techniques, hazards, emergencies, leadership, exploration, mines, cave diving, photography, etc, and end with a chapter on where to cave, further reading, bibliography, glossary and index.

The articles are well depicted in the line drawings of Annette Findlay, and in the main, the photographs of Paul Stillman with contributions from Chris Howes and Clive Westlake.

The book is written in an authoritative but readable manner, and avoids the dryness of many other manuals. My only comment, and I appreciate cost had a bearing on this, it is a shame that it was not printed in a hard back edition, perhaps when he re-prints?

A nice touch is Andrew’s generous acknowledgements to those who assisted him, and his dedication of the book to his wife Joanna.

Available from good bookshops and Bat Products at Wells, "The Complete Caving Manual" Copyright Andrew Sparrow, is available as a soft bound edition and retails at £14-99. Published by The Crowood Press Ltd, ISBN Number: 1 861260229.

EXPLOSIVES USER GROUP \ MRO SEMINAR:

This event postponed from May will now be held at Westbury Quarry, courtesy of Pioneer Aggregates Ltd, on Saturday 19th.July 1997.  Starting at 10.00, numbers will be limited, for further details contact Dany Bradshaw or the organiser Nigel Taylor.  The technical day, intends to cover the placement of anchors in other types of rock, such as Box stone sandstones, and Conglomerates / Draycott stone.  These will later be attacked with explosives to give the users an idea of the effective quantities required for such work. A special non-explosive rock breaking device will also be demonstrated by a commercial firm. Offers of assistance will be welcomed.

Please Note: Hard Hats & Suitable safety footwear mandatory.

WESSEX. v. BEC CRICKET MATCH:

Same date as above, and starting at 3.00pm, this should run on after the Westbury event, so there is no clash, why not attend both, details of course from the Little people, to whom I extend my condolences in advance!

BELFRY SITE CLEAN-UP, Saturday 9th.AUGUST:

The Committee depressed by the dilapidated state of the Belfry and site will host a clean-up on the above date.  WILL YOU HELP? IF NOT, WHY NOT? NO HELP ... NO MOAN!!!!!.

Well at long last, that's all for this month, can I leave the table now please?

Nigel Taylor, Hon. Secretary, 1996/7.  Belfry Table No. 20, Saturday 5th. July 1997.


 

Swimming! in St Cuthbert’s.

Over the past year various trips to Lake Chamber have been undertaken by myself, Mike O'Driscoll, Pete Mulholland and Adrian Hall.

The object of the exercise was to re-examine the passages and terminal sump on the other side of the lake.

What was surprising was the amount of flak and piss taking this has engendered.  Yes we may well be reinventing the wheel here ... but so what. People still climb Everest...and go to the North Pole ... "Because its there!" ... so why not us .... besides you never know .... you might find something.

About a year ago Mike, Pete and I went down and laid a dive line through the lake in order to belay high up on the far bank to assist the climb on that side. It is steep and very muddy so with a hand line is accessible in low water conditions.

I returned a couple of months later when the water was low and was able to free dive/duck through without tanks and got into the high level series on the far side. The ascent is very muddy and tube like.  Ascending 15 odd feet up past a loose squeeze round a boulder into a small chamber. There is an aural connection to the passages on the other side of the lake but this is very tight indeed and also quite pretty so I wouldn't try it.  Heading off to the left along the obvious route a narrow rift is reached. This time I turned back here as I’d only gone down to pick up my bottle anyway.

I returned twice over the next few months and made some experimental dives but made no further progress, then again I wasn't really trying I was playing with kit configurations and this seemed a good excuse to go for a swim.

Nothing happened for some months then as I was away in Yorkshire and then had hassles that prevented much activity.

Late in June this year myself, Pete and Adrian returned along with a couple of others to do some photos and get to the end.  The water was surprisingly high and very cold but we got through the lake and de-kitted. It's a bloody awkward place to remove diving kit even with single rigs so much swearing was done.  We trogged up to the chamber and to the rift where I squeezed through a higher bypass and gained entry to the last rift.  Ten feet along a very muddy passage ... tight too it opened out on the left to a descending rift 15 feet wide by 6 feet across and about 25 feet deep down to the water surface.  A great site ... a beautiful blue green sump pool; clear enough to see ten or so feet down into.  We all agreed it had "dive me" firmly emblazoned across the surface.

Up until now I have been unable to ascertain whether this has been dived before .. .it is recorded in the Cuthbert’s Report and looks like it was surveyed in the early seventies. I can't remember the names of the two concerned offhand but nobody seems to know what happened to them (any info gratefully received).

We plan to go back in the near future and dive .... even if only to have done it.

Looking down on the sump pool and at the survey it appears to go down then off to the right and depending on water levels my guess would be a depth of about 5m ish.  We will need to have a double rig for the diver for safety reasons but it’s not too bad a kit hump anyway.

As I said at the beginning we are not really fussed if someone has been in there before as its great fun anyway .... and it keeps you in practice.

I'll write some more up when we've done the next dive ...... .Jingles.


 

"Foul Air in Cave Digs. in which Explosives cords are used as an excavation agent"

As mentioned in my earlier "From The Belfry Table" Article, WHITE PIT diggers are experiencing considerable foul air problems.  There has been talk upon Mendip that cave exploration techniques involving explosives may be a contributory factor to this problem.

Foul air has long been a diggers nightmare, on Mendip, digs such as North Hill swallet, or Sanctimonious Passage in Hunters Hole and other such sites have produced large volumes of carbon monoxides, often exacerbated by the ingress of cowsh and sewerage giving rise to C02 and other noxious gases.  So the problem is not new, but, has some other activity now brought further hidden dangers to the cave-digger?

Are the plastic coated Explosive detonating cords now in regular use amongst the 'Bosch drill' brigade of cave diggers contributing to a new off-shoot of the problem?

These, detonated in the dig at White Pit at regular intervals may perhaps be the cause of plastic coating residues or gases combining with the muds in the dig spoil, and leaving residual gases other than standard Carbon Monoxides and Dioxides. It has been sensibly suggested by Vince Simmons that someone from the scientific side of the sport might make a worthwhile study of this problem.  I am not aware of any commercial knowledge or data regarding this, other than that given below, and I also agree that such work is worthy of support. PETN itself is Cardio- Vascular depressive, and I wonder if this could be adding to the user’s problems?

Certainly the chemical compositions of the polymers often left exposed from their shotholes might contain benzenes and other such material, and the quantities being fired at two or three strands per hole, giving larger M.I.C (Maximum instantaneous charge) than the older method of single strand cord in smaller diameter shotholes, obviously gives a greater amount of such exposed material, in addition to the greater explosive content in grams/metre.

Detonating cords contain PETN as their explosive agent, Pentaerythritol tetranitrate [PEIN] is wrapped in polypropylene countering yarns, which is then overlaid by plastic sheathing.  The common such cord used in caving is a white coated 12gr cord made by ExChem Explosives, and sold by them and through ICI Explosives (Dia: 5mm, +\-0. 2mm,6, 500 m/sec).  It used to be of 10gr content but now this is not readily available.  It is also the industry "Standard" against which LEDC and HEDC are further classified.  HEDC, High Energy Detonating Cord, is encountered as 20gr, 40gr, 80gr and 100gr.  These weights being the actual explosive content of the particular cord in grams per metre LEDC  [Low energy detonating cord] is found as Pentaflex 6 cord, however this contains 3.5gr/metre and not 6gr!!  When initiated by a detonator, the cord achieves a V.O.D [Velocity of Detonation] of between 6,000 and 7,000 metres per second.

Generally on Mendip 12gr cords were the norm.  In recent years licence holders have been able to obtain both 20gr [Red/Blk],40gr [Brown,8.2mm dia+\-0.2mm, 7000m/sec] and 80gr [Yellow/Green dia: 11.2mm+\-0.4rnrn, 7000m/sec] weights.  Often two strands of 20gr and a strand of 12gr are used in the same shothole, giving a 52gr/metre MIC.

ExChem Explosives give advice in their excellent range of product literature as follows:

"When explosives are detonated in circumstances other than those recommended by the manufacturer, unacceptable levels of other noxious gases including Carbon Monoxide and the Oxides of Nitrogen may be produced"

The ExChem 'Safety Information Sheet EXP6 [Update 1.7.1993] states:

"Avoid contact with other materials, in particular acids and bases & organic & inorganic, powerful oxidising or reducing agents, ammonia, nitro phenols, sulphur, gunpowder and other mixtures containing divalent sulphur, which may cause decomposition of the explosive core".

And further under the heading VAPOURS':

"Vapours-No vapours, but excessive exposure to P.E.T.N powder should be avoided, since inhalation or ingestion could lead to headaches".

This last paragraph however to my mind suggests that this refers to pre-detonation and not post detonation.

I shall shortly confer with ExChem Explosives regarding the subject, but would welcome all and any comment on this important safety issue, and now seek to generate discussion and research on it as suggested by Vince Simmons.

Nigel Taylor. Bristol Exploration Club, and MIExpE [Saturday 5th. July 1997].