Civil Engineering heritage: Scotland - Lowlands and Borders
Date 2007
Event ID 610042
Category Descriptive Accounts
Type Publication Account
Permalink http://canmore.org.uk/event/610042
This 16th century bridge over the Devon near Alloa is 442 ft in length, has ribbed main arches of 18 ft span and is 1012 ft– 20 ft wide. It has been described as the finest example in Scotland of a fortified bridge in which a series of twists are produced designed to effect the throwing of a body of horsemen into confusion. The eastern part is said to date from before 1555 and an extension westward completed before 1616.
This bridge, now confined to pedestrian use, was bypassed ca.1920 by a single-span steel truss bridge [Canmore ID 47153] alongside (now demolished). It had arrow-slitted abutment towers designed to harmonise with the old bridge. The trusses were of the Pratt or N-girder type with diagonals curiously in compression instead of tension. This departure from normal practice led to speculation that the girders may have been erected upside down.
R Paxton and J Shipway 2007
Reproduced from 'Civil Engineering heritage: Scotland - Lowlands and Borders' with kind permission from Thomas Telford Publishers.
