River Tay naturally. To aid this process and improve the health and resilience of the population a further 28 beavers will be released in Knapdale between 2017 and 2020, however there are no plans at present to release further beavers into the Tay. In the 19th century the Tay Rail Bridge was built across the firth at Dundee as part of the East Coast Main Line, which linked Aberdeen in the north with Edinburgh and London to the south. The bridge, designed by Sir Thomas Bouch, officially opened in May 1878. On 28 December 1879 the bridge collapsed as a train passed
Tay Rail Bridge of the top of the section below. The joint was then secured by bolts through matching holes on lugs (Crumlin) or flanges (Belah) on the two sections. This 'spigot and faucet' configuration was used (apparently without machining) on some Tay Bridge pier columns, but on some the bolts were relied upon to ensure correct alignment. (In the event, the joints were made using undersized bolts. This gave greater tolerances when assembling the column, but the less positive alignment of the column joints as initially assembled and after any subsequent 'working' of the joint would have weakened the column). On the