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An Encyclopedia of the History of Technology part 61

An Encyclopedia of the History of Technology part 61. This one of a kind encyclopedia presents the entire field of technology from rudimentary agricultural tools to communication satellites in this first of its kind reference source. Following an introduction that discusses basic tools, devices, and mechanisms, the chapters are grouped into five parts that provide detailed information on materials, power and engineering, transportation, communication and calculation, and technology and society, revealing how different technologies have together evolved to produce enormous changes in the course of history | PART THREE TRANSPORT The first compound locomotive was designed by the Frenchman Anatole Mallet and built in 1876 it was a 0-4-2 tank locomotive with two cylinders and ran on the Bayonne-Biarritz Railway. From this start various systems of compounding were developed by French German English and American engineers the principal variations being in the number and layout of cylinders employed. Some systems were successful some less so compounding became a subject of controversy as long as steam locomotives were being developed in the Western world opinions being divided about whether its inherent economy was not outweighed by the extra complication and expense in manufacture maintenance and operation. Possibly the least successful but best publicized compounds were those designed for the London North Western Railway by F.W.Webb from 1882 onwards. On many of these the two high pressure cylinders drove the front pair of driving wheels and the low pressure cylinder the rear pair front and rear not being coupled together in the interest of free running. Valve gear for the low pressure cylinder was operated by a slip eccentric with the ludicrous result when the locomotive had backed on to a train that if the front driving wheels slipped on starting instead of moving the locomotive forward to set the slip eccentric the rear wheels would revolve in reverse. Once these locomotives did get away they could run well. Two-cylinder compounds based more closely on Mallet s original ideas were more successful and were built by August von Borries locomotive superintendent of the Prussian State Railways from 1880 and in England by T.W. Worsdell from 1884 for the Great Eastern Railway and subsequently for the North Eastern. A 4-4-0 locomotive of this type was eventually rebuilt with three cylinders a single high-pressure cylinder inside and two low pressure ones outside and became the prototype of similar locomotives built by S.W. Johnson for the Midland Railway from 1901 onwards which