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The South Devon Railway engine houses were built in Devon, England, to power the atmospheric trains on the South Devon Railway between Exeter St Davids and Plymouth Millbay railway stations. They contained boilers that provided the power to pumps that created the partial vacuum to move the trains. Three of them still stand largely intact alongside the line. == History == |} The South Devon Railway was built by Isambard Kingdom Brunel who proposed moving the trains by atmospheric power. Brunel and other engineers travelled to Dalkey in Ireland in 1843 to view such a system undergoing tests on the Dublin and Kingstown Railway. There, Brunel's engineer of locomotives for the GWR, Daniel Gooch, calculated that conventional locomotives could work the proposed line at lower cost, but Brunel's concerns about the heavy grades led him to try the system regardless. The South Devon Railway directors agreed on 28 August 1844 to Brunel's proposal to use atmospheric power on their line. Brunel estimated that by reducing the double track locomotive worked line to a single track atmospheric line a saving of £8,000 per year could be made. Double track lines were favoured at that time even for lightly worked lines as this reduced the chances of a collision between trains, but the atmospheric system precludes the possibility of two trains travelling in opposite directions on the same section of track. The pipes were ordered from George Hennet, an engineering contractor who worked on many of Brunel's lines. He established a factory at Bridgwater, Somerset, to make them.〔 The line opened with conventional steam locomotives to Teignmouth on 30 May 1846 and was extended to Newton on 30 December 1846. The first piston carriage (which connected the train to the pipe) was delivered on 25 February 1847 and experimental running with atmospheric power started immediately. Public services were run to Teignmouth from 13 September 1847 and extended to Newton from 10 January 1848. At this time some trains were still worked by locomotives, but from 23 February 1848 all scheduled trains were powered by the atmospheric system.〔 The leather valve along the top of the pipe tended to dry out and air could then leak in, but this was mitigated slightly by the passing trains spraying water on the leather. The harsh environment of the line, which runs adjacent to the sea for much of its length and is often soaked with salt spray, presented difficulties in maintaining the leather flaps provided to seal the vacuum pipes, which had to be kept supple by being greased with tallow; even so, air leaked in, reducing the pressure difference. Many trains arrived at Exeter from the Bristol and Exeter Railway very late. Because the South Devon line was only equipped with a telegraph that linked the stations, the engines had to start pumping for when the timetable said that the trains were due to enter their section and then keep pumping until the train eventually passed. This meant that the engines pumped for twice as long as was necessary and meant that much more coke was consumed than would have been the case if pumping had only been undertaken when the train was actually ready to be run. The engine houses were connected to the telegraph system on 2 August 1848 but a lack of trained staff meant that it was not fully used. The railway company had set up a committee to investigate the efficiency of atmospheric working on 23 May 1848. In August Brunel gave a lengthy report on the system, and discussions with Joseph Samuda were held with a view to making repairs to the valve and guaranteeing its operation. On 29 August 1848 the directors, following Brunel's advice, recommended to the shareholders the suspension of atmospheric working. Atmospheric-powered service thus lasted less than a year, to 9 September 1848; the last engine pumping was at Exeter where an up goods train arrived in the early hours of 10 September. The engines and buildings were sold to other users, and most of the pipes were sold back to George Hennet for scrap. The atmospheric had cost the railway over £433,000 and about £81,000 was raised from the sales of redundant materials.〔 (Reprinted by Alan Sutton Publishing, 1985 (ISBN 0-862992-04-4)〕 Despite the building of engine houses on towards Plymouth and on the Torquay branch the system never expanded beyond Newton. Similarly, the proposal to use the same system on Brunel's Cornwall Railway between Plymouth, Falmouth and Padstow was not pursued.〔 Three of the engine houses (Starcross, Torquay and Totnes) are still standing and the location of two others (Turf and Dawlish) are clearly visible. A section of the pipe, without the leather covers, is preserved at Didcot Railway Centre mounted on a short section of track which is inclined to show the gradient of the line from Newton to Dainton. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「South Devon Railway engine houses」の詳細全文を読む スポンサード リンク
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