Decauville
Decauville (French: [dəkovil]) was a manufacturing company was founded by Paul Decauville (1846–1922), a French pioneer in industrial railways. Decauville's major innovation was the use of ready-made sections of light, narrow gauge track fastened to steel sleepers; this track was portable and could be disassembled and transported very easily. The first Decauville railway used 400 mm (15 3⁄4 in) gauge; Decauville later refined his invention and switched to 500 mm (19 3⁄4 in) and 600 mm (1 ft 11 5⁄8 in) gauge.
Starting in 1875, his company produced track elements, engines and cars. Those were exported to many countries, in particular to the colonial possessions of European powers. In 1878 Paul Decauville was given permission to build the Jardin d'Acclimatation railway in order to demonstrate passenger transport operations on his railway system during the Exposition Universelle of 1878.
The French military became interested in the Decauville system as early as 1888 and chose the 600 mm (1 ft 11 5⁄8 in) gauge track to equip its strongholds and to carry artillery pieces and ammunition during military campaigns. Decauville track was used during the French military expeditions to Madagascar and Morocco.
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