The Tay Bridge Disaster

At 7:08 p.m., on December 28, 1879, a North British Railway train carrying 70 passengers and 5 crewmen from Edinburgh to Dundee departed from its next-to-last stop, Saint Fort Station, two miles south of the Firth of Tay.

To reach Dundee, the train would cross the renowned 86-span Firth of Tay Bridge—the world’s longest, an engineering work of such importance that its chief engineer, Thomas Bouch, had been knighted by Queen Victoria for designing it.

The two-mile-long bridge carried only one rail line, so the railway had instituted a token system to manage two-way traffic. The driver of a northbound train was required to pick up a baton from a signal cabin located on the southern approach to the bridge, then deposit the baton at another cabin on the northern side after crossing. No train was permitted to cross without the baton, thus ensuring that two trains traveling in opposite directions could never occupy the bridge at the same time.

That evening, a signalman named Thomas Barclay was on duty at the southern cabin. It was a lonely job, so Barclay’s buddy, John Watt, had stopped by to keep him company. At 7:13 p.m., as the Edinburgh-to-Dundee train came by, Barclay handed the baton to the driver, then turned his attention to updating his logbook and sending the requisite telegraph to his counterpart at the northern cabin. Meanwhile, Watt was standing at the window, watching the train. As it moved out onto the bridge, Watt was surprised to see sparks flying from its iron wheels—indicating that the wind was pushing the train sideways with such force that its wheel flanges were grinding against the sides of the iron rails.

About three minutes later, as the train approached the middle of the bridge, Watt saw a bright flash of light—and then nothing. The flash, the sparks, and the train’s tail lamps had suddenly disappeared.

Watt told Barclay that the train seemed to have derailed. Skeptical, Barclay attempted to telegraph the northern signal cabin to confirm the train’s arrival in Dundee, but the line was dead. The two men then tried walking out onto the bridge to investigate, but the wind was too strong—so they stumbled through the darkness down to the shoreline instead.

From this vantage point, they were horrified to see that a 3,000-foot section of the Tay Bridge had simply vanished. They quickly notified the railway, and rescue operations were initiated—but by morning, it was clear that the 75 souls on the train couldn’t possibly have survived the hundred-foot plunge into the frigid waters of the Tay.

The Tay Bridge collapse was the result of the combined effects of wind load and chief engineer Robert Stephenson’

In 1862, North British Railway acquired the Edinburgh-to-Dundee line, which had great economic potential but was constrained by the need to carry its trains across two estuaries—the Firth of Forth and the Firth of Tay.

This ferry system had been in operation since 1850, and while it was hardly an optimal means of moving trains across a body of water, it was an extraordinary engineering achievement nonetheless.

In 1870, an act of Parliament authorized North British Railway to bridge the Firth of Tay.

Thomas Bouch, a young civil engineer, was chosen to lead the project, and he was an excellent choice for the job. In addition to designing innovative ferry systems, he had also earned considerable notoriety for building several major railways and for pioneering the use of lattice girders in railroad bridges.

The bridge was completed in 1875, and it quickly became an important transportation link between Edinburgh and Dundee.