| Belfry Bulletin No 529, Spring 2008 - The Caving Ladder |
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Page 4 of 19
Your Flexible Friend ... the Ladder
by the late Dave Irwin,
in his memory
The use of wooden rigid ladders in cave exploration,
including cane ladders of the Far East, is probably as old as The Mists of
Time, but the use of the flexible ladder is another story. Whilst looking for
references relating to this subject Ray Mansfield mentioned to me that he
believed that the Chinese were using such ladders in caves during the 14th -
15th centuries but he could not relate to any particular source. Published
accounts of exploration have stated that the first use of a flexible ladder was
during the exploration of the Macocha Chasm in the late 18th century. So it .may come as a surprise when it will
be shown that a Mendip caver can claim the honour some 105 years earlier!
John Beaumont [c.1650 - 1731]
Details of the early exploration of Lamb Leer Cavern are
well known to most Mendip cavers based upon four letters sent by John Beaumont
to the Royal Society between 1676 and 1683. Due to the misleading Lowthorpe
abridged reprint in 1705, together with several later editions of this work,
the included errors were perpetrated by many later authors including Herbert
Balch. Very few later researchers consulted the original documents;
investigative work by Trevor Shaw resolved the problem correctly identifying the
original documents. The references given here will relate to the original
sources, namely the Royal Society Transactions and Collections to which
Beaumont sent four letters, two in 1676; the others in 1681 and 1683. The
topics were wide ranging but included details of 'rock plants' [Crinoids] he
had investigated; an account of the ailments afflicting both miners and cattle,
and he also submitted detailed descriptions of some of the Mendip caves he knew
at Wookey Hole and Cheddar. His descriptions of the caves were based upon first
hand knowledge the largest of which was located on Harptree Hill above the
village of West Harptree. The exploratory trips into this cave were carried out
by Beaumont accompanied by local miners and the published account of its
exploration is a revelation. It is factual and, allowing for the presentational
style of the time, his account would be readily accepted as an exploratory
report in modern caving publications. The cave - Lamb Leer Cavern.
The then entrance shaft, now known as the Beaumont Shaft,
was passed without comment implying that this was done using the miners
techniques of the day, fixed wooden ladders or stemples or a combination of
both. However, on reaching the head of the 20m pitch into Main Chamber he
describes the descent in great detail- This is important for it implies that
the technique was not commonly used by the miners. Beaumont wrote that:
... a vast Cavern opens it self, so that by the light of our
Candles we could not fully discern the roof, floor, nor sides of it; I
encouraged the Miners by offer of a double Salary to any that would go down in
to it, they all refusing, I fastened a cord about me, and ordered them to let
me down gently after the Rocks, but being down about two Fathom I found the Rocks to bear away from me, so
that I could touch nothing to guide my self by, and the rope began to turn
round very fast, whereupon I ordered the Miners to let me down as quick as they
could, and upon the descent of 12 Fathom I came to the bottom, where untying my
cord I went about to search the Cavern ... This Cavern is about 60 Fathom in
the circumference, above 20 Fathom in height, and about 15 in length, it runs
along after the Rakes, and not crossing them as the leading Vault does. At the
breast of this Cavern, which terminates it to the West, I discovered some good
Lead-Ore, and all other kindly sorts of Earth and Stones which usually lie with
it...
Not wanting to repeat the discomfiture experienced on the
first descent and wishing to get his miners down into the chamber to work for
ore and Bole earths , Beaumont
... got a Ladder of Ropes to be made for an easy descent
into this great Cavern, and caused Miners to sinck ten Fathom deep in the
bottom of it, just before this breast, and we had always some leading of Ore in
our working, but finding often little Caverns in our work, which are not so
kindly for one as firm ground, we at length desisted. ...
The discomfort referred to by Beaumont during the descent
was also experienced by McMurtrie when he made the same descent by rope soon
after its re-opening in 1880.
The 18th and 19th centuries
Though the publications of the Royal Society were widely
read throughout Europe the use of ladders in cave exploration was not common
practice for some time. Absolon relates that rope ladders were used to explore
the Macocha Chasm or Abyss near Brno in southern Moravia in the Czech Republic
during the 18th century . Shaw refers to
a 'proto-ladder' devised by Lazarus Schopper in his attempt to descend the
chasm in 1723. The hair-raising design was that '... he drove pegs through his
rope to serve as footholds.'
A rope ladder proper was used to descend into the main
chamber of Grotte des Demoiselles in France in 1780. However, from the mid 19th
century the flexible ladder was in common usage for cave exploration in Europe.
Edward Hanke von Hankenstein devised a folding ladder to aid his exploration
of the Macocha Chasm in the 1860s. Shaw notes that the
... earlier use of ropes followed the then established
mining procedures but Hankenstcin used folding ladders. Each was approximately
5 m long and could be assembled to a length of up to 60 m. The contraption
weighed some 100 lbs.
How it was constructed and from what it was made is not
stated.
Meanwhile in Britain ...
During the first quarter of the 19th century a large number
of caves had been or were being explored. On Mendip the Banwell caves were
accessible to the public during 1824-25; in 1837 Cox's Cave was accidentally
found and opened for the public a year later. In the north some fifty caves
were explored during this period including Goyden Pot [1832] and Ingleborough
[Clapham] Cave in 1837.
It was not until the 1840s that the two best known shafts in
the Dales, namely Gaping Gill [Ghyll] and Alum Pot received the attention of
the 'curious'. To explore these required
a very different technique to that already used to explore the 'easier' caves.
The first attempt at Gaping Gill was made about 1842 when John Birkbeck [1817-1890] was lowered
down the shaft on a rope. How he clung to the rope is not known but it is
possible that the end of the rope was lashed to a wooden bar upon which
Birkbeck sat. Be that as it may, it was a hairy escapade. William Howson, a local schoolmaster, was to
later write that:
... this chasm has been descended to a depth of one hundred
and ninety feet and there is no landing place until this depth is reached. ..
According to Beck, Birkbeck made another attempt in the
following year when, though not proceeding beyond the ledge, now known as the
Birkbeck Ledge, he was able to plum the lower section of the shaft determining
that the depth to the floor of the shaft was a further 150 ft.
Slightly earlier, through the 1830s and 1840s, Alum Pot
created some local interest for guides could be hired for a descent into Long
Churn Cave. The trip ended beyond Dr. Bannister's Handbasin at the head of the
12m Dolly Tubs, which had yet to be descended. On their return, the visitors
climbed a short wooden ladder to avoid a wetting in the Handbasin.
Intrigued as to what lay at the foot of the Alum Pot shaft,
Birkbeck and William Metcalfe [1815-1888] led a party of 10 including Howson
into Long Churn with the intention of descending Dolly Tubs. For the trip they
brought with them ropes, pulleys and a fire-escape belt. Ropes were used to
descend Dolly Tubs and from The Bridge Howson was strapped into the fire-escape
belt and lowered to the floor some 18m below but due to lack of adequate tackle
to explore beyond this point the trip was called off.
Another attempt by the same group was made a year later but
this time the descent would be by means of a winch slung from beams placed
across the top of the main shaft. Of these attempts Howson recorded that the
first down to the rock bridge was unsuccessful for fatigue
... and wet prevented the party from doing more than
reaching the bottom, but next year the same adventurous spirits descended from
the summit of the Pot by means of a windlass fixed on two baulks of timber laid
across the chasm. ...
The timber beams were left in place until 1893 when they
were declared to be rotten. On the
second occasion the final sump was reached. The situation remained thus until
1870 when Birkbeck and Metcalfe were joined by William Boyd Dawkins and three
ladies. In all 10 persons went down making a successful descent to the
bottom. Short lengths of ladder and
ropes was lowered enabling the shorter pitches below The Bridge to be
tackled. What type of ladder is unclear,
some believe that they were rigid structures, lashed together for the longer
pitches.
By the 1890s the exploration of caves in the Yorkshire Dales
became a regular activity of the members of the Yorkshire Ramblers Club [YRC]
and many of the entrances were by then well known though the caves were not
explored until the early years of the 20th century. To undertake the
exploration of Meregill, Juniper and other notable classics rope ladders were
regularly used.
The YRC was formed in 1892 and one of the earliest projects
was another attempt to bottom the Gaping Ghyll main shaft; the first since
Clibbon's unsuccessful descent in 1882, though he too reached Birkbeck's
Ledge. In 1895 one of YRC founding
members, Edward Calvert, investigated the top of the shaft determining that
rope ladders would be the right choice of equipment in order to make the
descent. Knowing that the measured depth of the shaft was about 360 ft he and
others set-to and commenced building manilla rope and wooden rung ladders. For various reasons the planned trip was
delayed and, as Beck commented this was to cost Calvert ... the honour of the
first descent, ...
Meanwhile Eduard Martel [1859-1938] had planned a visit to
Great Britain to address the 6th Geographical Congress in London, in August
1895. He took full advantage of the invitation and transformed his visit into a
tour of various caving regions in order to collect information that was later
published in his Irlande et caverns anglaises. This included a tour of the
northern caves and investigations of the deep potholes that were known to exist
not far from Enniskillen in Ireland. The site of special interest was the as
yet un-descended Gaping Ghyll. Consequently he communicated with James Farrar,
the landowner and obtained permission to make another attempt. Martel brought
with him some 300 ft of ladder and some length of rope. The ladder by itself would not reach the
floor of the shaft some 360 ft below. This was achieved by lowering the whole ladder 60 ft down the shaft. To
reach the ladder Martel had to first climb down the holding rope complete with
telephone and its cable and lifeline. That day, 1st August 1895, made caving
history by bottoming the shaft and recording initial details of the great
chamber.
Though bitterly disappointed at being 'pipped to the post
Calvert and his companions finally made the first British descent in the
following year on the 9th May 1896 using a Bosun's Chair. YRC also used ladders for the exploration of
Long Kin West during October 1896 and for the exploration of Rowten Pot in July
1897.
Ladders used by the cave explorers at the end of the 19th
century were of mixed design. Some explorers were using rope sides with a
combination of wood and rope rungs. The wooden rung being introduced to
stabilise the ladder during the climb preventing the awful closing of the rope
sides making it very difficult to climb unless they were belayed separately.
Others preferred to pay the weight penalty by having their ladders made up of
rope sides and all wooden rungs. In 1898
the 1st edition of Encyclopaedia of Sport included a section on cave exploration.
... As the sport of cave exploration and the descent of
potholes is a comparatively new one, and as little is known about it in England
outside those districts where it is practised, a few words on its evolution are
necessary to the understanding of its methods.....
This section was written by John Green, Edward Calvert,
Frank Ellet and Thomas Gray; all 'first wave' YRC potholers. By 1910 YRC had
480 ft [146m] stock of ladder, which was probably a mixture of metal/rope rung
combination as well as the accepted design of wooden rung/rope ladder.
So by the 1890s flexible ladders were in common use by cave
explorers. But what of the design? A ladder with sides and rungs of rope would
be extremely difficult to climb and not least tiring. Furthermore the rope
would stretch and the sides collapse together so that the rungs hung in loops.
A nightmare to say the least. To overcome the problem each side rope would
require a separate belay point. The well known lifeline signals were introduced
to caving about this time.
However ladder design had progressed by this time and two
basic designs were regularly used; the pros and cons of each were obviously the
subject of much discussion. The most rigid - stable of these designs was the
rope sides and wooden rung configuration but they were heavy and extremely
bulky. Martel used this design for his Gaping Ghyll descent.
In order to reduce both weight and bulk a compromise design
between the true rope ladder and the wooden rung configuration was developed.
It took the form of a ladder comprising rope sides but a mixture of rope and
wood rungs thus keeping the ladder stable for the climber. It is well described
in the Encyclopaedia of Sport, 1898:
ROPE-LADDERS The ladders used are made with sides of
half-inch rope, and rope rungs of slightly smaller material spliced in. A wooden rung in every four or five may be
added to keep the sides apart, but to have all the rungs of wood is too great
an increase in weight and the bulk to be recommended, though some explorers
prefer them. The ladders are most useful in lengths of 40 or 50 feet, made to
join either by spring hooks or by lashing. One of the ladders should have its
top bar made of wrought-iron and provided with three rings or eyes, the use for
which will be seen later. ... Another method of descent is by rope-ladders.
This is suitable for places which descend in a series of drops or
"pitches," where there are ledges of varying widths. With a total
length of 150 feet of ladder much may be done.
Having plumbed a depth of, say, 100 feet from the surface,
the ladder is tied to two ropes (or to both ends of one rope) of not less than
½ inch diameter, one at each end ring of its top bar. If possible, a plank should be fixed across
the mouth of the shaft, over which the ropes attached to the ladder may hang,
in order to avoid knocking down any loose earth or rock. The ropes carrying the
ladder should be made fast to a couple of stakes driven into the ground a
little distance from the lip of the "pot," and then, secured by a
safety rope, paid out by hand over a pulley fixed into the plank, the exploring
party will in turn descend. It may be found that the place the party have
reached is not the bottom, and that the plumb-line is again required. Assuming
it reveals another considerable drop, the ladder will have to be lowered until
its head is level with the ledge occupied by the party, and then either be made
fast there or, preferably, above.
The raising and lowering of the ladder will be facilitated
by a length of sash cord being tied to the middle ring of the top bar of the
ladder, passed through a pulley on the beam, and allowed to hang down the hole.
Then the men on the first landing place will be able to help, by steadying and
holding it while the ropes on the surface are being secured. This procedure may
be repeated until the actual bottom is reached.
It must be remembered that the descent and ascent by
rope-ladders is a very toilsome proceeding, and that practically no rest can be
taken while on the ladder itself beyond getting breath, as the ladder swings
away from the vertical line, which throws the man's weight almost entirely on
his hands and arms.
For this reason, if for no other, a windlass is to be
preferred for a deep descent which cannot be negotiated by a series of drops
where rests may be taken. ...
Though the above was written by YRC members, the first journal published by that club in
1899 contained a review of the caving section written by one 'L.M.' The reviewer noting that the authors of the
article called caving "mountaineering reversed" took issue with this
and also on the matter of ladder design.
... Frankly describing it as a sport, its writers make no
apologies for pursuing it, regardless of public opinion, which always condemns
climbing more or less, and cannot too utterly abhor the more apparent futility
of its allied sport. ... The technical side is dealt with at some length, and
the article gives a careful explanation of the most successful methods of
exploring caves and descending potholes ... If there is a point upon which it
is possible to join issue with the authors it is upon the form of rope-ladder
best adapted for this work. In spite of its extra weight, a ladder with
alternate rungs of wood and rope, or at least every third rung of wood, is to
be preferred to the ladder with one wooden rung in every four of five
recommended. Climbing a rope-ladder for even a short distance is exceedingly
arduous, and the stiffness and rigidity imparted by the additional wooden rungs
more than balance the increased difficulty of getting the ladder to its point
of usefulness. ...
By the time of the 1911 edition of the Encyclopaedia of
Sport the section relating to ladder design had been completely rewritten
stating that:
... ladders used are made with sides of half-inch diameter
rope with hardwood rungs. Experience shows that it is very important that the
rungs should not be more than eight or nine inches apart - a longer step
becomes excessively fatiguing on a long ascent. ...
The article included several interesting photographs
including the work of Cuthbert Hastings. How many editions of the encyclopaedia
was published is unknown.
Noon's Hole in the north of Ireland
YRC visited northern Ireland to explore one of the two
famous shafts, the 80m Noon's Hole entrance shaft at Whitsun, 1907. Only armed
with 20m of ladder the YRC team
... turned their attention to Noon's Hole or Sumera, a deep pot-hole with a grisly reputation due
to the fate of an informer who was thrown down about a century ago. ... Our rope ladder was only 70 feet long,
and as we could hardly make up more than 200 feet of life line, Mr. Lemon ...
kindly lent us two 120 feet ropes, which we need to raise and lower the 70 feet
ladder. It was the lot of our London member to make the first and only
descent...
The London member was none other than Ernest A. Baker who
reached a depth of 44 m [143 ft] before the return climb to the surface. A
magnificent achievement.
Martel made his famous descent down the Gaping Ghyll [Gill]
Main Shaft, excepting the first 70 ft which he climbed down on the rope holding
the ladder, by climbing the rest in much the same way as he did when descending
the great shaft at Padirac. The same shaft was bottomed by YRC in the following
year.
A Novel Design
In 1894, Harold Dawson of Bradford, who ... possesses a
complete apparatus for the descent of these pot-holes ... made a descent of
Alum Pot via Long Churn using
... a wire-rope ladder, 42 feet long, divided into three
sections (of 14 feet), fastened and unfastened by means of 'dog -clasps', so
that in bearing a great weight it was utterly impossible for the clasps to come
unloosened. This ladder was invaluable, it was flexible, and each one of the
party of three had a section wound round his body, (immediately under the
armpits) the ladder being of such width that it rested on the hips, and
required no fastening over the arms, thus leaving them quite free; it was
carried this way, and when any depth of a drop was encountered, one, two, or
three sections were unbound and clasped together as the occasion required ...
The use of wire-rope is significant for this is the first
mention of any deviation from the standard rope sides in common use at this
time. How the rungs were constructed is not stated, it is probable that Dawson
used wooden rungs but he could have used metal rungs which, if so, would
probably have been made of steel. The structurally sound duralumin was not in
common usage in large scale manufacture until metal aircraft structures became
commonplace during the 1930s. It was, however, a significant advance in ladder
design that was, for a time, a one-off and not followed up by his
contemporaries.
...and on Mendip
The early Mendip pioneers have often been criticised for not
using ladders when descending the pitches in Lamb Leer Cavern, Swildon's Hole
and Eastwater Cavern. Balch in particular came in for severe criticism for
seemingly staring progress in the face. It must be pointed out, without going
into detail, that the rope technique adopted by the Mendip pioneers, in
particular in Eastwater Cavern was similar to that used by Mendip miners.
Baker, who was a well respected alpinist would never have agreed to work with
Balch under these conditions had he not thought it safe; however this is
another story and is the subject of another paper. Ropes were not completely replaced by ladders
for some time. An account of a descent of Eastwater, in 1942, clearly
illustrates the manner by which some cavers explored this cave.
Visiting Mendip from the north one Simpson and his friend
joined up with two cavers from Bristol including one Fisher [the leader]. Ready
for the descent they
had ... a good long rope, which Fisher said we would use on
the verticals. ... The only thing I remember after this was a continual
scramble along narrow passages and down vertical rifts with the rope getting in
the way most of the time. Eventually we came to a series of verticals down
which the rope was necessary. Fisher belayed on a convenient boulder and
proceeded to climb down, using the rope as a hand rail. We followed one by one
and found ourselves at the head of another short pitch. Down we went again
still cling[ing] to the rope, only to find another steep pitch following. This
time we had to abseil down, and what a laugh Fisher and I had. We had safely
reached the foot of the pitch and Holt [Simpson's friend] prepared to follow.
Somehow or other he got the rope around his knee about halfway down and
finish[ed] the latter half of the pitch almost head first. The last man fared
better, as he wound the [rope] twice around his waist, presumably for safety's
sake, only to find himself securely hung up about 6 ft. from the floor with the
rope getting ever tighter around his waist. Fortunately we were able to ease
him up whilst he extracted himself from the coils of rope, his only injury
being his pride. We had now finished with the rope and continued on our
scramble down to the sump, which we reached safely.
The return route was vastly different up a series of short
water-worn verticals, which we climbed with ease. This brought us out at the
bottom of the second rope pitch which we now had to climb. Fisher led the way
and we followed one by one with little delay. We were now at the bottom of the
first pitch and it looked a very tricky climb. Fisher made a very determined
effort, and after a terrific hand over hand scramble on the last few feet,
safely reached the head of the pitch. With Fisher at the top, we used the rope
as a lifeline and after much panting and cursing reached the top without
mishap.
Suffice to say that the party returned to daylight all in
one piece!
Balch first used ladders in 1903 during his exploration of
the upper series and opening up of the western extensions in Wookey Hole.
In 1914 Baker, made an attempt to bottom the Swildon's Hole
Forty Foot Pot. Using a rope ladder he reached the bottom and progressed a
further 60m before reaching another wet pitch, the Twenty Foot Pot. Lack of
tackle prevented further exploration of the cave. Wet conditions foiled Baker's
second attempt in 1915 and the weather intervened again in the exceptionally
wet years of 1919-1920. Even so a number of groups attempted to reach the
Twenty Foot Pot but the volume of water flowing down the Forty Foot Pot was
again too great to enable a safe descent to be made. British weather can often
be one of extremes. The wet conditions of the two previous years gave way to
one with the longest drought of the 20th century during 1921. Breaking his
journey to Europe for an Alpine holiday, Baker accompanied by his son, Gerard
and cousin, Alan Baker, met Chandler and travelled to Mendip. Taking full
advantage of the dry weather the party descended the cave and it was not long
before they stood at the top of the Twenty Foot Pot. The way on was clear and eventually a ...
curious double fall, ... was reached. The party, ready to beat a retreat remained at the top of the pots
whilst Baker continued down the passage
stopping just short of Barnes' Loop. After building a cairn he returned and the
party left the cave. It was only after the event that Baker informed Balch of
what had been found. The furious Balch
sprang into action and organised a large party which descended the cave on the
1st August. Baker's cairn was reached
and a section of the party continued down to the sump, known to them as The
Trap. The weather remained dry well into late Autumn enabling a series of trips
to be arranged principally to survey and photograph the new passages. Instead
of the leisurely approach to caving on Mendip, perhaps three or four trips a
year, Balch organised at least eight trips during that period. Rope and wooden
rung ladders were borrowed from the small stock that had been built up by the
recently formed UBSS enabling several of their members, including E.K. Tratman,
to join the Balch teams.
Rope ladders in the 20th century
Ladders as described in the Encyclopaedia of Sport were
widely used by YRC and the Yorkshire Speleological Association (YSA). The
latter was formed in 1906 by Eli Simpson and others, and by about 1910 both
clubs had accumulated sizeable stocks of ladder sufficient to undertake all the
known northern caves. However, though all ladders were built from rope and
wooden rungs there was no standardised width of rung.
Inspecting early photographic material taken between c. 1908
and 1921 a variety of rung widths were used. As early as 1889 Martel used a
wide rung ladder to descend the Padirac shaft. However, by 1910 photographs
taken at this time of Gaping Ghyll [Gill] show a narrow flat rung with a side
rope pitch of about 7 inches. Even in the early 1920s UBSS were using ladders
with 30 cm wide rungs. This can be
clearly seen in the Savory photograph of Edgar Tratman at the bottom of the
Swildon's Forty Foot Pot. Another photograph of the Twenty Foot Pot, c. 1922,
from the Molly Hall collection at Wells and Mendip Museum also shows a similar
width of rung in use. The wide rung ladder design remained in use for some
considerable time and was part of the ladder stock during the early years of
the Bristol Exploration Club, 1935- c. 1940. A photograph of BEC members, including Harry Stanbury outside Lamb Leer
Cavern, c. 1938, in his photographic collection clearly shows how bulky this
equipment really was. During the post 2nd World War years rung width was
reduced to a standardised length of about 20 cm. Quite apart from the rung
width the wooden rung design took on two forms: a circular or rectangular
section. They were made from seasoned straight grained hard wood. Round rungs
were frequently used, the rung end being pushed through the rope strands which
locked into a shallow groove close to the rung ends. The rung was then
permanently locked to the rope sides by whipping above and below the rung.
Though this design was widely used it was acknowledged that the rope was
extremely vulnerable to severe chafeing when hung close to the rock face.
Another problem caused several climbers moments of discomfort. The round rungs
would rotate and unless the boot was well located on the rung the climber would
find himself coming off the ladder!
The rectangular rung overcame the two basic disadvantages of
the circular rung. As for the circular design the rectangular rungs were
frequently located by whipping or lashing and in other cases a wooden peg was
driven through the rung and rope, a method much favoured by CPC during the
1950s. In the north most were built in lengths of 20 or 25 feet to minimise the
problems of transportation, bulk and weight; the 25 ft ladder weighing in at
about 10 lb. (dry) and about 13 lb. (wet). For long pitches the ladders were
linked by knotting or eye-thimbles were threaded into the rope ends and clipped
together by karabiners among other techniques.
In the post 2nd WW years many designs emerged as a result of
clubs developing their own designs and build standards. The Cave Research Group
published details of the more commonly used methods of ladder construction in
its various editions of British Caving and in the 1962 Some Technical Aids for Cave Exploration. Clubs too published articles discussing
the merits of various designs typified by one written by Plowes of the Orpheus
Caving Club. Their ladders were built
in 15 ft and 30 ft length and were built from 1¾" manilla rope (approx.
½" diameter) and the rungs were made of oak or beech measuring 7½" x
1½" x ½"
... though the thickness, if the wood is not such good
quality, might be increased to 5/8". Choose from straight grained pieces,
avoid the 'sap wood" which is softer & be wary of possible splitting.
Half inch diameter holes, drilled in the rungs at 6"
centres, carry the ropes. The rung protects the rope from damage by abrasion
... The rungs are secured by a method of lashing. The effect of this method is
to thicken the rope ... Over riding of [the] rungs being practically
impossible. ...
The Electron Ladder
By the start of the 1930s French caving had emerged as a
significant force in the speleological world and many cavers and there came
about a major reassessment of caving equipment generally being used. Much of it
was bulky, heavy and required large parties to transport the gear to its point
of use. During the late 1920s the famous French caver R. de Joly began
constructing a number of specialised tools as aids to cave exploration. Among
these 'inventions' was a device known as the 'Galet', a folding frame in the
form of a triple trestle, that allowed ladders to be kept away from sloping
surfaces reducing abrasion to the ropes and rungs. About this time another innovation was a
major redesign of caving ladders where he replaced natural fibre rope with wire
rope. The life of the ladder was considerably improved and the concept was
quickly adopted by many cavers not only in France but throughout the rest of
Europe and remained in general use up to the early 1960s.
De Joly's major breakthrough came in 1930 when he introduced
the 'Electron' ladder which was an all metal construction. This was revolutionary for it eliminated
nearly all the disadvantages of the rope-wooden rung combination at a stroke.
The ladder was constructed using flexible wire rope to which were attached
duralumin tubes. The whole assembly was
some 75% lighter than the conventional rope ladder and much less bulky enabling
smaller parties to work as a team. Being of metal it was much less susceptible
to abrasive damage and, though it still required regular inspection, corrosion
was a relatively minor problem.
During the pre 2nd WW years cavers were fully aware of the
de Joly design but still clung to the wood rung ladders. In fact the debate
relating to the various ladder designs continued into the 1950s. In the event
it was not until the 1960s that the Electron ladder was in regular use. The
difficulty of climbing the ladder was a reason but the root cause of cavers
shunning the structure was simply perception. The slightness of the design gave
little encouragement to those used to climbing the seemingly more substantial
outlines of the rope ladder. Secondly, it was generally acknowledged that rope
ladders were easier to climb. Their extra bulk held it in a vertical position
enabling the climber to move up and down on the same face of the ladder whilst
holding the side ropes which meant that the centre of gravity of the climber
was close to the ladder. Attempting to climb an Electron ladder in the same
manner causes the climber to lean back, placing the body weight onto the arms
and hands. To bring the centre of gravity position of the climber closer to the
ladder a new climbing technique was devised where each boot is on different
sides of the ladder - popularly known as 'making love to the ladder! Basically
the technique is still used today.
Writing in the Craven Pothole Club Journal Smith reviewed
methods of manufacturing caving ladder and at the end made some comment on the
Electron ladders built by a fellow club member, Brindle.
... At this stage I ought to say something about the de Joly
/ Brindle type metal ladders. But words fail me! We tried out this ladder on
the open pitch at Rift Pot and after this experience I would recommend that it
should not be used on any pitch greater than 25 feet. To give them their due,
they are light, fairly strong (although I have some reservations on this score)
and they are easy to handle in confined spaces. But in my view they tend to put
the whole weight of your body on the wrists and particularly so when you have
been used to climbing wooden ladders where the weight of the body is taken by
the upper part of one's arms. ...
However, after much discussion and debate the rope ladder
eventually lost out to the lightweight Electron structure. By the 1960s cavers
had broken away from the regular formal club meet and were now caving more
frequently and in smaller groups. The increase in personal transport; the
extensions to the motorway system saw cavers' habits changing dramatically. The
increased freedom of mobility saw groups caving in most caving regions in the
country on a regular basis, whereas previously it had only been possible on
Bank Holidays or during their Annual Holiday. As a consequence of this change,
the lightweight ladder and light synthetic ropes then coming onto the market
swept the old equipment aside enabling small teams to undertake quite extreme
caving trips.
In Britain the idea of building an Electron ladder was first
taken up by Harry Stanbury of the Bristol Exploration Club about the time of
its reformation in 1943. Scrounging materials from all manner of sources,
remember it was during the middle of the 2nd World War, he built an 'electron'
ladder using 5/8 inch [1.6 cm] diameter 20 SWG [0.9mm] duralumin tubing. The
0.08 inch [2 mm] diameter wire rope was passed through holes drilled close to
the tube ends, round a 2 BA bolt [approx 4.5 mm dia] shank and looped through
an aluminium spacer and out of the other hole [see photo]. Together with C.
Drummond and Dan Hasell the trio tried the ladder out on Swildon's Forty Foot
Pot on 3rd April 1943. Harry wrote in the BEC log book that the
ladder
exceeded all expectations. The ladder
still exists and was given to the Club a few years ago for safe keeping. It is
an important piece of caving history and is now kept in the Club library.
In 1946, UBSS members, John Pitts and Charles Barker,
co-discoverer of G.B. Cave in 1939, spent a holiday in Ireland with the
intention of exploring Dunmore and Mitchelstown Caves. In a speech given in
1998, Pitts talked of their wanderings and of the caves they explored.
Travelling around the countryside on Barker's motor-cycle, caving kit had to be
kept to an absolute minimum and so instead of taking a standard rope ladder
with them they constructed a light-weight ladder
... of wire and duralumin tube tailored for the pitch in the
Old Cave at Mitchelstone (sic). We spaced the rungs as far apart as we dared in
order to reduce the weight and took the minimum amount of rope that we hoped
would be enough for tethers. Rope in those days of course was hemp.
A couple of years later Luke Devenish of the MNRC and WCC
attempted to developed his own lightweight ladder. The problem was that Luke,
who was always brimming over with enthusiasm, was no engineer. His first
efforts used one or two duralumin plates for the rung between which a 3/16 in
diameter wire rope was sandwiched, all of which was held in place by a bolt
passing through the plates and strands of the wire rope. The weight of this was
10lb. for 25 ft of ladder. He made a variant which reduced weight further by
omitting the second plate, the nut being clamped against the wire rope
separated by a washer.
None of these trials made it into club 'production' but
Devenish persisted. He next devised a tubular rung configuration using ½ inch
diameter, 18 SWG duralumin tube and 3 mm diameter galvanised steel wire rope
which was passed through holes drilled at the ends of each rung. To fix the
wire to the tube each tube end was plugged with Plaster of Paris just beyond
the drilled holes - the reason will soon become clear. The wire rope was then
passed through the tube at which point the strands exposed inside the tube were
separated using a screwdriver then was poured molten solder to fill up the void
between the Plaster of Paris and the outer edge of the rung in order to prevent
the cable slipping. Unbelievable! Even Devenish commented that it ... proved
unsatisfactory.
Don Coase of the BEC, an engineer, improved on the Stanbury
design during the late 1940s by evolving a system whereby two plugs were
inserted into both rung ends, the outer being a tapped hole for a 2 BA Allen
screw which, when in place pinched the wire rope to form a locking device. This
worked well but had the disadvantage of damaging several strands of the wire
rope.
About 1951-52 a simple construction was devised by Ralph
Lewis of the Westminster Spelaeological Group and remained in common use for
the next two decades. The construction was simple in that a taper pin,
specially ground at its smaller end, enabled it to be passed through the gap
between the wire rope and one side of the duralumin rung trapping the wire
against the opposite side of the rung wall. The design was first described in
detail by Bryan Ellis in January 1957 , another appearing in 1967 by Cedric
Green. An in-depth article on ladder
construction published in 1963 outlined the technology as it was at that time.
By the late 1960s two popular designs of ladder construction
had been established once cavers had realised the disciplines associated with
each type. The first used Talurits that were swaged above and below the dural
rung and were extremely effective providing the right dies were used. The other
being a combination of plugs, steel pins and epoxy resins. The methods are still in use today
For some time there was no accepted rung pitch except that
it was somewhere between 25cm and 30cm but the larger rung pitch made climbing
tiring. In 1959 a caver was trapped in a narrow vertical tube in Peak Cavern.
Although a ladder was being used it became impossible for the man to climb back
up as the rung pitch was 12", too far apart to allow him to place his boot
on the rung above and so start the climb out and free himself. From that time
it became an accepted rule that rung pitching should be 25 cm. Today the
commercial ladders have the rung pitch set at 25 or 30 cm.
Colour coding of ropes and ladders
During 1962 the Mendip clubs agreed a colour coding system
for club equipment. Problems had occurred following a number of cave rescues
where considerable trouble had to be taken sorting out which piece of equipment
belonged to which club. During 1961 BEC circulated the other major Mendip clubs
suggesting a colour coding scheme. Though one or two clubs used the same colour
it was eventually sorted and the following system adopted : ACG -Yellow ; BEC -
Blue ; Cerberus SS - Grey ; MCG - Pink ; MNRC - Green ; SMCC - Black ; UBSS -
Orange ; WCC - Red and WSG - Brown.
When this article was started it was thought that it would
be just a couple of pages of notes but in the end it became a semi-major
undertaking to check as many references as possible. A discussion on the rope
techniques used by the Mendip pioneers is an article just about completed that
runs in parallel with this on ladders. Where it will be published is at the
moment undecided.
Dave Irwin, Priddy. December, 2003
Acknowledgements
My thanks to Ric Halliwell [CPC], Ray Mansfield [UBSS], Don
Mellor [CPC], Martin Mills [SMCC] and Graham Mullan [UBSS] for help obtaining
details and copies of notable articles and books relevant to the topic.
Eds note: This
article was provided on paper and had to be scanned in. Further Optical
Character Recognition work was undertaken to convert it to text.
News from the Belfry
Work on the extension has proceeded at a furious pace over
the last few months. Considering that the planning application went in back in
June 1999 it will be good to get it finished.
The downstairs will be a new tackle store and workshop
befitting for a club that prides itself in exploration. Upstairs will be a
members bunk room.
Work is also underway on a feasibility study to extend into
the roof space to create a Wig Memorial Library. Clearly this would be another
massive undertaking and we are carefully reviewing the possibilities.
As most of you will be aware the Mendip Farmers Hunt has purchased Underbarrow Farm behind the Belfry. The Committee and Trustees are hard at work looking at the implications of this.
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| Last Updated on Thursday, 31 January 2008 12:48 |