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Since its opening in 1864
meticulous maintenance has ensured that the bridge has never closed. It is
easy to forget that this structure which was designed in the 1830s, built
in the 1860s and intended entirely for horse-drawn traffic, now carries a
staggering total of 4 million cars a year. The fact that it also spans
across a gorge with sheer rock face either side made it's building much
harder. Back then they did not have the use of today's power tools or air
transportation, if equipment sent over by boat it still had to be taken up
the rocks
The
history of the building of the Clifton Suspension Bridge spans a period of
more than 100 years from concept to completion.
The
story begins in 1754 when William Vick, a wealthy Bristol wine merchant,
left £1,000 in his will with instructions that the sum should be invested
until it reached £10,000. He had been informed that this sum would be
sufficient to build a stone bridge across the Avon Gorge which would be
free to travellers. It must be remembered that in the mid 18th century
Clifton was still a hamlet, and on the other side of the gorge in Leigh
Woods were private estates. The grand Clifton terraces were many years in
the future. The reason for Vick's desire for a bridge is therefore
something of a puzzle.
By
the early 19th century wrought iron had become available and iron
suspension bridges developed quickly in Britain and America. In 1819
Thomas Telford began his Menai Suspension Bridge with a span of 174 metres
linking the island of Anglesey with the North Wales mainland.
In
1829, 75 years after his death, William Vick's legacy had reached £8,000
and a committee was set up to decide how to build a bridge. It was quickly
realised that a stone bridge as specified by Vick would cost £90,000. An
iron suspension bridge would be cheaper but would require tolls. An Act of
Parliament was passed allowing these changes and on 1st of October a
competition was announced with a prize of 100 guineas (£105).
Four
designs were shortlisted with Brunel being placed second. However, he
quickly arranged a meeting with the leading judge and soon convinced him
that technical objections to his design were unjustified. Within two days
Brunel was proclaimed the winner and also appointed engineer for the
project, his favourite 'Egyptian' design being chosen. What the original
winner of the competition thought of the judges' change of heart is not
recorded.
In
1831, £20,000 short of the necessary funds, work began. Only a few weeks
later the Bristol Riots broke out, the bloodiest civil disturbances to
take place in 19th century England, with the mob in control of the city
for two days until dispersed by cavalry. Business confidence collapsed and
it was over four years before work on the bridge resumed.
In
1836 an iron bar 305 metres long was hauled across the Gorge and a basket
to transport men and materials slung from it. Brunel himself made the
first crossing and the basket stuck at the lowest point 60 metres above
the river. Brunel climbed out of the basket, up the rope and released the
cable from the jammed pulley. By 1843 the two towers were completed but
funds were exhausted. To save money the committee reduced the height of
the towers, scrapped the sphinxes on them and the cast iron cladding
around them designed to tell the story of the bridge. By 1853 the time
span allotted by Parliament expired. The committee sold the ironwork,
machinery and equipment to pay the contractors and much of the material
was used on Brunel's Royal Albert Bridge linking Devon and Cornwall at
Plymouth. Brunel died in 1859 at the age of 53 through overwork and 40
cigars a day without ever seeing the completion of his bridge which he
referred to in his diary as: 'My first love, my darling'.
Ironically,
Brunel's early death inspired the completion of the bridge. The
Institution of Civil Engineers decided to finish the bridge as a memorial
to him. By coincidence the Hungerford Suspension footbridge in London,
designed by Brunel, was about to be demolished to build a railway bridge
and the chains were bought for £5,000. A new bridge company was formed in
May 1860. It was estimated that £45,000 would be needed to complete the
project and by December £30,000 had been raised. A new Act of Parliament
confirmed that the bridge would be completed under the supervision of Sir
John Hawkshaw and W H Barlow. Happily for today's road traffic these
engineers decided to use three chains instead of two and to widen the
roadway from 7 metres to 9 metres. To enable construction of the temporary
staging to begin, a light rope was passed from one bank to the other. One
story has it that this was done by flying it across on a kite!
Early
in 1863 timber scaffolding was placed around the towers and an iron wire
was fixed across the Gorge. To construct the chains a footway was made up
of six iron wire ropes each 335 metres long to which timber planks were
bound. Two wire handrails were fixed to each side and at head height was
another wire on which ran a light frame on wheels used to carry each link
of the bar chains. Besides being a walkway, this wire bridge supported the
chains and as each new link was added wooden blocks were placed
underneath. The bar links were assembled at the rate of 40 a day and when
the three chains on the south side were completed the walkway was
dismantled and re-rigged for the northern side. A total of 4,200 bar links
were assembled. By May 1864 the chains were completed and 162 wrought iron
suspension rods were fixed to the chains by bolts. The two large girders
that run the full length of the bridge supply the main support for the
road deck and divide the roadways from the footpaths. These girders were
built in 5 metre sections and attached to the suspension rods by bolted
plates. Eighty cross girders were then bolted underneath at right angles
to make the structure rigid. Interlocking sleepers were placed on the
cross girders and then at planks of timber 5 centimetres thick were laid
at right angles. In July 1864 the last cross girder was in place and as a
safety test 500 tonnes of stone were spread on the road and footpath. The
bridge sagged 18 centimetres in the middle, well within acceptable limits.
On 8 December 1864 the
ceremonial opening took place. After 110 years of uncertainty William
Vick's vision had finally been realised.
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