Civil Engineering heritage: Scotland - Lowlands and Borders

This striking sandstone masonry bridge, crossing about 90 ft above the Tyne Water at the north end of Pathhead, was designed by Telford as part of the Edinburgh to Morpeth road improvement, now the A68. It has five semicircular masonry arches, each of 50 ft span and was built by James Lees from 1829–31 at a cost of about £8500. The footpaths are partly carried on shallower arches carried 2 ft forward of the main spans but bonded to them. This ‘ascititious’ or ‘external’ arch and pier pilaster feature, as Telford called it, was intended to make the bridge look more slender. It is not altogether successful as the eye tends to move restlessly between the two arches affecting the harmony of the elevation. His adoption of this feature at Dean Bridge, Edinburgh, where the external arches extend 5 ft forward of the main spans, is much more effective in producing a slenderness effect.

Problems were encountered in founding the bridge. ‘An iron rod was driven 56 ft without impediment so piling became out of the question. Telford, Jardine & other persons of science and skill were consulted and in conformity with their directions, the piers were founded upon platforms composed of double tiers of memel logs and of three tiers of stones from Craigleith quarry. This has occasioned an extra expense of about £2000 and it was unexpected as the ground had been bored’, but what was thought to be bedrock 13 ft below the surface turned out to be ‘large round stones’.

R Paxton and J Shipway 2007

Reproduced from 'Civil Engineering heritage: Scotland - Lowlands and Borders' with kind permission of Thomas Telford Publishers.