The original Tay Bridge opened on 1 June 1878 — a single-track railway viaduct approximately 3.2 km long across the Firth of Tay between Dundee and Wormit in eastern Scotland. It was the longest railway bridge in the world. Queen Victoria crossed it on her substantial return from Balmoral the following year and knighted its designer Thomas Bouch in June 1879.
Bouch was 56, the substantial pre-eminent Scottish railway engineer of his generation. He had been awarded the substantial commission for the proposed Forth Bridge further south on the same eastern Scottish coast. His design for the Tay Bridge had cost approximately £350,000 and had been built between 1871 and 1878 by approximately 600 labourers; the Board of Trade had inspected and approved the completed structure shortly before opening.
The bridge stood for nineteen months.
The night
The evening of 28 December 1879 brought a westerly gale to eastern Scotland, with sustained wind speeds estimated at approximately 130 km/h. The Edinburgh-Dundee evening passenger train departed Edinburgh on schedule at 4:15 PM and approached the southern end of the Tay Bridge at approximately 7:13 PM with 75 passengers and crew aboard.
Eyewitnesses on the Dundee shore watched the train’s lighted carriages enter the central section of the bridge — the High Girders section, comprising thirteen wrought-iron lattice spans that stood approximately 27 metres above the water to allow shipping passage beneath. Approximately three minutes after the train entered the High Girders, the entire High Girders section collapsed into the Firth of Tay, carrying the train with it.
All 75 people aboard died. Approximately 46 bodies were recovered over the following weeks; the remainder were never found.
The investigation
The Wreck Commissioner’s investigation through the spring of 1880 produced a verdict of multiple causes converging. The Bouch design had underestimated the wind loading on the high-profile lattice spans (Bouch had used the substantively standard British wind-load estimate of approximately 480 Pa, against the substantively higher estimates that French and American engineers of the period were adopting). The cast-iron columns supporting the girders had manufacturing flaws (‘blowholes’ from imperfect casting that had been filled in with substantively cosmetic cement-and-iron-filing mixtures). The maintenance regime had been substantively inadequate; loose bolts and cracked lugs documented during the spring 1879 inspection had not been substantively repaired.
The verdict assigned primary responsibility to Bouch personally. His design for the Forth Bridge was substantively cancelled and substantively reassigned to a different engineering team (John Fowler and Benjamin Baker, whose 1890 cantilever-truss bridge still stands). Bouch died of a nervous collapse in October 1880, aged 58 — less than ten months after the Tay Bridge verdict.
What replaced it
A replacement Tay Bridge was designed in the early 1880s with double-track construction, heavier wind-load specifications, and improved cast-iron quality control. The replacement opened in 1887 and still stands.
The William McGonagall poem ‘The Tay Bridge Disaster’ (1880) — the worst poem in the English-language Victorian canon, universally agreed to be so — substantively commemorates the 75 dead with accidentally-humorous lines including:
Oh! ill-fated Bridge of the Silv’ry Tay, I must now conclude my lay By telling the world fearlessly without the least dismay, That your central girders would not have given way, At least many sensible men do say, Had they been supported on each side with buttresses, At least many sensible men confesses.