Diagram showing a side elevation of the swivel bridge over the entrance lock of St Katharine's Docks, London. Also shown are the transverse section of ribs, roller frame, top and bottom rings and pivot; plan of the roadway showing planking and carriage guides, and plan of the arch ribs, top rings and connecting plates. The bridge was part of Thomas Telford's (1757-1834) redevelopment of the Docks in 1828. Illustration from Telford's 'Atlas to the Life of Thomas Telford, civil engineer', published in London in 1838.
© Science Museum / Science & Society Picture Library