Isambard Kingdom Brunel
Isambard Kingdom Brunel was an English civil engineer and mechanical engineer who is considered "one of the most ingenious and prolific figures in engineering history", "one of the 19th-century engineering giants", and "one of the greatest figures of the Industrial Revolution, changed the face of the English landscape with his groundbreaking designs and ingenious constructions". Brunel built dockyards, the Great Western Railway, a series of steamships including the first purpose-built transatlantic steamship, and numerous important bridges and tunnels. His designs revolutionised public transport and modern engineering.
Though Brunel's projects were not always successful, they often contained innovative solutions to long-standing engineering problems. During his career, Brunel achieved many engineering firsts, including assisting his father in the building of the first tunnel under a navigable river and the development of the, the first propeller-driven, ocean-going iron ship, which, when launched in 1843, was the largest ship ever built.
On the GWR, Brunel set standards for a well-built railway, using careful surveys to minimise gradients and curves. This necessitated expensive construction techniques, new bridges, new viaducts, and the Box Tunnel. One controversial feature was the "broad gauge" of, instead of what was later to be known as "standard gauge" of. He astonished Britain by proposing to extend the GWR westward to North America by building steam-powered, iron-hulled ships. He designed and built three ships that revolutionised naval engineering: the , the , and the .
In 2002, Brunel was placed second in a BBC public poll to determine the "100 Greatest Britons". In 2006, the bicentenary of his birth, a major programme of events celebrated his life and work under the name Brunel 200.
Early life
Isambard Kingdom Brunel was born on 9 April 1806 in Britain Street, Portsea, Portsmouth, Hampshire, where his father was working on block-making machinery. He was named Isambard after his father, the French civil engineer Sir Marc Isambard Brunel, and Kingdom after his English mother, Sophia Kingdom.His mother's sister, Elizabeth Kingdom, was married to Thomas Mudge Jr, son of Thomas Mudge the horologist.
He had two elder sisters, Sophia, the eldest child, and Emma. The whole family moved to London in 1808 for his father's work. Brunel had a happy childhood, despite the family's constant money worries, with his father acting as his teacher during his early years. His father taught him drawing and observational techniques from the age of four, and Brunel had learned Euclidean geometry by eight. During this time, he learned to speak French fluently and the basic principles of engineering. He was encouraged to draw interesting buildings and identify any faults in their structure, and like his father he demonstrated an aptitude for mathematics and mechanics.
When Brunel was eight, he was sent to Dr Morrell's boarding school in Hove, where he learned classics. His father, a Frenchman by birth, was determined that Brunel should have access to the high-quality education he had enjoyed in his youth in France. Accordingly, at the age of 14, the younger Brunel was enrolled firstly at a college in Caen, then at Lycée Henri-IV in Paris.
When Brunel was 15, his father, who had accumulated debts of over £5,000, was sent to a debtors' prison. After three months went by with no prospect of release, Marc Brunel let it be known that he was considering an offer from the Tsar of Russia. In August 1821, facing the prospect of losing a prominent engineer, the government relented and issued Marc £5,000 to clear his debts in exchange for his promise to remain in Britain.
When Brunel completed his studies at Henri-IV in 1822, his father had him presented as a candidate at the renowned engineering school École Polytechnique, but as a foreigner, he was deemed ineligible for entry. Brunel subsequently studied under the prominent master clockmaker and horologist Abraham-Louis Breguet, who praised Brunel's potential in letters to his father. In late 1822, having completed his apprenticeship, Brunel returned to England.
Thames Tunnel
Brunel worked for several years as an assistant engineer on the project to create a tunnel under London's River Thames between Rotherhithe and Wapping, with tunnellers driving a horizontal shaft from one side of the river to the other under difficult and dangerous conditions. The project was funded by the Thames Tunnel Company and Brunel's father, Marc, was the chief engineer. The American Naturalist said, "It is stated also that the operations of the Teredo suggested to Mr. Brunel his method of tunnelling the Thames."The composition of the riverbed at Rotherhithe was often little more than waterlogged sediment and loose gravel. An ingenious tunnelling shield designed by Marc Brunel helped protect workers from cave-ins, but two incidents of severe flooding halted work for long periods, killing several workers and badly injuring the younger Brunel. The latter incident, in 1828, killed the two most senior miners, and Brunel himself narrowly escaped death. He was seriously injured and spent six months recuperating, during which time he began a design for a bridge in Bristol, which would later be completed as the Clifton Suspension Bridge. The event stopped work on the tunnel for several years.
Though the Thames Tunnel was eventually completed during Marc Brunel's lifetime, his son had no further involvement with the tunnel proper, only using the abandoned works at Rotherhithe to further his abortive Gaz experiments. This was based on an idea of his father's and was intended to develop into an engine that ran on power generated from alternately heating and cooling carbon dioxide made from ammonium carbonate and sulphuric acid. Despite interest from several parties, the Admiralty included, the experiments were judged by Brunel to be a failure on the grounds of fuel economy alone, and were discontinued after 1834.
In 1865, the East London Railway Company purchased the Thames Tunnel for £200,000, and four years later the first trains passed through it. Subsequently, the tunnel became part of the London Underground system, and it remains in use today, originally as part of the East London Line, now incorporated into the London Overground.
Bridges and viaducts
Brunel is perhaps best remembered for designs for the Clifton Suspension Bridge in Bristol, begun in 1831. The bridge was built to designs based on Brunel's, but with significant changes. Spanning over, and nominally above the River Avon, it had the longest span of any bridge in the world at the time of construction. Brunel submitted four designs to a committee headed by Thomas Telford, but Telford rejected all entries, proposing his own design instead. Vociferous opposition from the public forced the organising committee to hold a new competition, which was won by Brunel.Afterwards, Brunel wrote to his brother-in-law, the politician Benjamin Hawes: "Of all the wonderful feats I have performed, since I have been in this part of the world, I think yesterday I performed the most wonderful. I produced unanimity among 15 men who were all quarrelling about that most ticklish subject—taste".
Work on the Clifton bridge started in 1831, but was suspended due to the Queen Square riots caused by the arrival of Sir Charles Wetherell in Clifton. The riots drove away investors, leaving no money for the project, and construction ceased.
Brunel did not live to see the bridge finished, although his colleagues and admirers at the Institution of Civil Engineers felt it would be a fitting memorial, and started to raise new funds and to amend the design. Work recommenced in 1862, three years after Brunel's death, and was completed in 1864. In 2011, it was suggested, by historian and biographer Adrian Vaughan, that Brunel did not design the bridge, as eventually built, as the later changes to its design were substantial. His views reflected a sentiment stated fifty-two years earlier by Tom Rolt in his 1959 book Brunel. Re-engineering of suspension chains recovered from an earlier suspension bridge was one of many reasons given why Brunel's design could not be followed exactly.
Hungerford Bridge, a suspension footbridge across the Thames near Charing Cross Station in London, was opened in May 1845. Its central span was, and its cost was £106,000. It was replaced by a new railway bridge in 1859, and the suspension chains were used to complete the Clifton Suspension Bridge.
The Clifton Suspension Bridge still stands, and over 4 million vehicles traverse it every year.
Brunel designed many bridges for his railway projects, including the Royal Albert Bridge spanning the River Tamar at Saltash near Plymouth, Somerset Bridge, the Windsor Railway Bridge, and the Maidenhead Railway Bridge over the Thames in Berkshire. This last was the flattest, widest brick arch bridge in the world and is still carrying main line trains to the west, even though today's trains are about ten times heavier than in Brunel's time.
Throughout his railway building career, but particularly on the South Devon and Cornwall Railways where economy was needed and there were many valleys to cross, Brunel made extensive use of wood for the construction of substantial viaducts; these have had to be replaced over the years as their primary material, Kyanised Baltic Pine, became uneconomical to obtain.
Brunel designed the Royal Albert Bridge in 1855 for the Cornwall Railway, after Parliament rejected his original plan for a train ferry across the Hamoaze—the estuary of the tidal Tamar, Tavy and Lynher. The bridge consists of two main spans of, above mean high spring tide, plus 17 much shorter approach spans. Opened by Prince Albert on 2 May 1859, it was completed in the year of Brunel's death.
Several of Brunel's bridges over the Great Western Railway might be demolished because the line is to be electrified, and there is inadequate clearance for overhead wires. Buckinghamshire County Council is negotiating to have further options pursued, in order that all nine of the remaining historic bridges on the line can be saved.
When the Cornwall Railway company constructed a railway line between Plymouth and Truro, opening in 1859, and extended it to Falmouth in 1863, on the advice of Brunel, they constructed the river crossings in the form of wooden viaducts, 42 in total, consisting of timber deck spans supported by fans of timber bracing built on masonry piers. This unusual method of construction substantially reduced the first cost of construction compared to an all-masonry structure, but at the cost of more expensive maintenance. In 1934 the last of Brunel's timber viaducts was dismantled and replaced by a masonry structure.
Brunel's last major undertaking was the unique Three Bridges, London. Work began in 1856, and was completed in 1859. The three bridges in question are arranged to allow the routes of the Grand Junction Canal, Great Western and Brentford Railway, and Windmill Lane to cross each other.
Far older than the Suspension Bridge, Isambard Brunel's innovative rotating bridge Brunel Swivel Bridge, Bristol at the entrance to Bristol's Floating Harbour was originally built to carry a road across his new Entrance Lock to the City Docks. It was built in 1849 in the same dockyard as the SS Great Britain and by the same firm. It still survives today, next to the 1872 Entrance Lock where it provided an essential crossing until made redundant by the Plimsoll Swing Bridge, commissioned in 1968.
The deck is 33 m long, weighs about 70 Tonnes, and, although derelict, can still rotate. The bridge is a Grade 2* listed national heritage asset and on Historic England's Buildings At Risk Register, where its condition is described as ‘very bad’.
It is now the subject of a major restoration project.