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Marc Brunel was one of the most innovative
engineers of his day. He was born on April 25, 1769 in Hacqueville,
France. He joined the French Navy but had to flee France because of his
outspoken royalist views. He emigrated to America where he became the
Chief Engineer of New York and worked on many engineering projects.
In 1798 Brunel met Major-General Hamilton,
the British aide-de-camp and secretary at Washington, and over dinner
had the idea that made him his first fortune
At the dinner table was a fellow countryman,
M. Delabigarre, who had just arrived from England. Conversation turned
to ships and navies, and then to the manufacture of wood blocks for
sailing ships. These wood blocks housed the sail ropes. A
seventy-four-gun ship of the line needed 1400 blocks. The blocks were
made by hand. If we multiply 1400 by the number of commissioned ships in
an expanding navy, we begin to get some idea of the problem. Moreover,
because the blocks were subject to storm, sea water, wind, ice and sun,
each ship would sensibly set sail with a hold full of replacements for
the voyage.
To spell it out, the English navy was
producing millions of handmade wood blocks every year, and throwing
millions of split and perished items into the ocean. Here was a
manufacturing opportunity, and Marc Brunel seized it.
He sailed from New York on January 20 1799,
and landed at Falmouth in March, intent on making his fortune. It is not
difficult to imagine the suspicion that English officialdom would have
had for a Frenchman, from the land of bloody revolution, sailing from
America, the land of rebellion. But Marc Brunel had the advantage of an
introduction from his friend, General Hamilton, to Earl Spencer of
Althorp (Lady Dianas ancestor). The loyal support of Lord and Lady
Spencer were to prove invaluable to the young American, and later to his
famous son, Isambard Kingdom Brunel.
In 1809 Brunel was shocked to see the
lacerated feet of returning veterans of the Battle of Corunna. He
designed a set of machines that produced good strong boots and shoes in
nine different sizes. 24 disabled soldiers manned the factory. Like all
his designs, Brunel's boots were a great success and in 1812, the
Foreign Secretary, Lord Castlereagh, persuaded him to expand production
in order to fill the army's total requirements.
Peace, however, came close to ruining Brunel,
as contracts were cancelled. So he spent time in the Kings' Bench
Prison, Southwark for debt. Fear that Brunel was leaving his adopted
country for Russia led the government to pay off Brunel's creditors.
Fortune was not the only thing Brunel was
seeking in England. He came to England looking for the English
girl with whom he had fallen in love with in France, for he had escaped
from revolutionary France with his life, but without his heart. This he
had lost to Sophia Kingdom, a young English girl staying with friends in
Rouen.
Marc Brunel found his sweetheart in London,
married her, and eventually settled in Rotherhithe. Here he began a
famous piece of engineering, a tunnel under the River Thames, and the
first tunnel under a river anywhere in the world.
In 1825, Brunel began construction of a
tunnel under the Thames River between Rotherhithe and Wapping.
Previous attempts, in 1801 and 1807, were unsuccessful mainly because
excavation met quicksand, a sand through which fast moving water causes
the sand to be held in suspension. The general opinion, formed in
engineering circles at the time, was that there was no practical means
of tunneling under the Thames.
However, Brunel patented the "tunneling
shield" in 1818 - a device that made possible tunneling through
waterbearing strata.
In essence,
it was a cylinder pushed ahead of the tunnelling equipment, to provide
advance support for the tunnel roof. Something like this was needed when
tunnelling in soft or unstable ground. The shield was pushed forward by
hydraulic jacks, about four inches at a time. While the iron shield held
up the wet sandy muck, workers lined the tunnel walls with brick.
Work on the tunnel began in
1825. It started at Rotherhithe, on the south bank, and Marc Brunel laid
the first brick himself, the second being laid by his 19-year-old son,
Isambard Kingdom Brunel. The design of the tunnel was to allow two
carriages and a footpath. But construction was slow. Each foot of tunnel
required 5500 bricks to be laid. On several occasions the works were
flooded, and on one of these seven workers were drowned (the River
Thames at that time was an open sewer). Isambard saved the lives of
several men but was seriously injured himself.
During the period
1828-1835, all work on the tunnel was halted because the money had run
out. Further financial aid was obtained from the government, however,
and finally on March 25, 1843, the 1300 feet long and 35 feet wide
tunnel was opened. There were insufficient funds available to build the
ramps needed for carriages, in accordance with Marc Brunel's original
design, so it opened as a foot tunnel, charging a small toll. About
50,000 people walked through the tunnel during the first two days of
operation, and more than one million used it in the first four months.
The tunnel was later adapted for railway use, and remains to this day as
an important part of the East London Line on the London Underground
system. It is a measure of the quality of the original construction that
no major refurbishment was needed until the 1990s, some 150 years since
the tunnel first opened.
Today, in the Rotherhithe Station, by the
entrance to the tunnel, is a commemorative plaque erected by the
American Civil Engineers and the British Institution of Civil Engineers.
It celebrates Brunels tunnel as one of the most important civil
engineering sites in the world. Today Brunels patented method is used
universally; workers dig within a protective shield, and build the walls
as they dig. Without the principle he established in the 19th century, none of the
underground systems in the world would have been constructed. The
Channel Tunnel, linking his country of birth with his country of
adoption, would not have been possible.
Sir Marc Isambard Brunel (1769 - 1849) was knighted in 1841 by Queen
Victoria in recognition of his engineering achievements.
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