South Devon Railway
The South Devon Railway was a broad-gauge railway incorporated in 1844 to extend the Great Western Railway from Exeter to Plymouth along one of the most demanding and scenically spectacular routes in England — the coast wall along Dawlish and Teignmouth, where the railway runs literally at sea level between red sandstone cliffs and the English Channel, and the severe South Devon Banks at Dainton, Rattery, and Hemerdon where gradients reach 1 in 36 and challenged even the most powerful Victorian locomotives. Engineered by Isambard Kingdom Brunel, the SDR was the site of his most ambitious and ultimately ill-fated technical experiment: the atmospheric railway.
Brunel's atmospheric system — in which trains were propelled by differential air pressure in a continuous pipe between the rails, with a leather valve sealing the slot through which the driving arm passed — operated between Exeter and Newton Abbot from 1847 to September 1848, when persistent failure of the leather valves due to corrosion and rat damage forced its abandonment. The atmospheric experiment cost the SDR enormous sums and delayed the Plymouth extension, but the principle — replacing locomotive hauling with a fixed propulsive force distributed along the route — anticipated elements of modern linear motor traction theory. The Dawlish sea wall, built to carry Brunel's atmospheric pipe and the railway alongside it, remains one of Britain's most photographed and operationally vulnerable railway alignments, periodically damaged by winter storms.
The SDR was absorbed into the GWR on 1 February 1876. The South Devon Railway heritage line at Buckfastleigh preserves a section of the former GWR Ashburton branch in the same South Devon territory, and G.J. Churchward served his engineering apprenticeship at the SDR's Newton Abbot Works.
About
The South Devon Railway (SDR) was a British pre-grouping railway incorporated by Act of Parliament on 4 August 1844 to build an extension of the broad-gauge Great Western Railway from Exeter to Plymouth. Engineered by Brunel, the SDR's most famous and unsuccessful experiment was the use of the atmospheric railway system, in which trains were propelled by the differential air pressure in a continuous pipe between the rails. The atmospheric system worked from 1847 to 1848 between Exeter and Newton Abbot before being abandoned because of corrosion of the leather flap valve, and the line was converted to conventional locomotive traction.
The SDR's curving, steeply-graded line through the South Hams (the so-called 'sea wall' along the Dawlish coast and the South Devon Banks at Dainton, Rattery and Hemerdon) was a particular challenge for its locomotive department. Many of the SDR's celebrated saddle-tank engines were built at Newton Abbot Works, where G. J. Churchward later served his apprenticeship.
The SDR was absorbed into the GWR on 1 February 1876, completing the GWR's monopoly on the West of England broad-gauge mileage. The Dawlish sea wall remains a heavily-photographed and operationally-vulnerable piece of British railway infrastructure today.
