Bouch, Sir Thomas

SUBJECT AREA: Civil engineering

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b. 22 February 1822 Thursby, Cumberland, England

d. 1880 Moffat

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English designer of the ill-fated Tay railway bridge.

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The third son of a merchant sea captain, he was at first educated in the village school. At the age of 17 he was working under a Mr Larmer, a civil engineer, constructing the Lancaster and Carlisle railway. He later moved to be a resident engineer on the Stockton \& Darlington Railway, and from 1849 was Engineer and Manager of the Edinburgh \& Northern Railway. In this last position he became aware of the great inconvenience caused to traffic by the broad estuaries of the Tay and the Forth on the eastern side of Scotland. The railway later became the Edinburgh, Perth \& Dundee, and was then absorbed into the North British in 1854 when Bouch produced his first plans for a bridge across the Tay at an estimated cost of £200,000. A bill was passed for the building of the bridge in 1870. Prior to this, Bouch had built many bridges up to the Redheugh Viaduct, at Newcastle upon Tyne, which had two spans of 240 ft (73 m) and two of 260 ft (79 m). He had also set up in business on his own. He is said to have designed nearly 300 miles (480 km) of railway in the north, as well as a "floating railway" of steam ferries to carry trains across the Forth and the Tay. The Tay bridge, however, was his favourite project; he had hawked it for some twenty years before getting the go-ahead, and the foundation stone of the bridge was laid on 22 July 1871. The total length of the bridge was nearly two miles (3.2 km), while the shore-to-shore distance over the river was just over one mile (1.6 km). It consisted of eighty-five spans, thirteen of which, i.e. "the high girders", were some 245 ft (75 m) long and 100 ft (30 m) above water level to allow for shipping access to Perth, and was a structure of lattice girders on brick and masonry piers topped with ironwork. The first crossing of the bridge was made on 26 September 1877, and the official opening was on 31 May 1878. On Sunday 28 December 1879, at about 7.20 pm, in a wind of probably 90 mph (145 km/h), the thirteen "high girders" were blown into the river below, drowning the seventy-five passengers and crew aboard the 5.20 train from Burntisland. A Court of Enquiry was held and revealed design faults in that the effect of wind pressure had not been adequately taken into account, faults in manufacture in the plugging of flaws in the castings, and inadequate inspection and maintenance; all of these faults were attributed to Bouch, who had been knighted for the building of the bridge. He died at his house in Moffat four months after the enquiry.

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Principal Honours and Distinctions

Knighted. Cross of St George.

Further Reading

John Prebble, 1956, The High Girders.

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