The bridge had been constructed only a few years earlier, to carry the railway between Dundee and Wormit. It was initially seen as an engineering triumph - its successor is the longest rail bridge over water in Europe.
The current Tay Bridge
Although construction began in 1871, the first train did not cross until 1877 and the bridge opened to passengers in June 1878. Challenges included changes to the design when the bedrock proved much deeper than expected; the 2.75-mile length to be spanned, done in a curving sweep; and the need for height so ships sailing to Perth could pass beneath. The bridge was supported on cast-iron piers, with the cast-iron columns supporting its girders strengthened by wrought-iron cross-bracing.
On the night of 28 December, a ferocious storm swept across the bridge. At 7.13pm, a train set off north along the bridge; it never reached the other side. The storm took not only the train, but also the central spans of the bridge itself into the river. In fact, the train was found still within the bridge's girders when divers examined the scene. (The locomotive was later recovered and returned to service.) 46 bodies were recovered, but at least 59 and perhaps as many as 75 people died.
Investigations into the bridge included testing of the girders in London, at the Kirkcaldy Testing Works (now a museum). David Kirkaldy was able to confirm that the cast iron lugs used to fasten tie bars to the bridge columns, and the ties themselves, were inadequate. Combined with design flaws (notably a lack of allowance for wind loading, which meant the bracing was inadequate); the questionable quality of castings by the foundry; and poor maintenance, they left the bridge unable to withstand the storm of 28 December. The Court of Inquiry which investigated the disaster did not reach complete agreement on its causes, but did broadly agree on these points.
Engineer Sir Thomas Bouch had designed the bridge, and was responsible for its construction and maintenance; he was knighted in part because of this work. Unsurprisingly, the effect of the disaster on his reputation was devastating. At the time of the disaster, he had been working on the proposed Forth Bridge, but the design work was transferred elsewhere. He died the following year, before the official inquiry was complete.
A new bridge was built parallel to the old one, opening in 1887 - it incorporates some wrought iron girders from its predecessor. Parts of the original bridge's piers still remain visible. A memorial at the end of the bridge in Dundee lists the names of the known victims.
