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An Encyclopedia of the History of Technology part 41

An Encyclopedia of the History of Technology part 41. 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 TWO POWER AND ENGINEERING The first company to exploit electric motors on a large scale was Siemens and their first major customer was the Prussian state mines. Electricity in mining however developed fairly slowly. Although some mine winders were electric before the First World War it was only in the 1920s that mine electrification became widespread. A major industrial use of electric power was the iron and steel industry. Several ironworks adopted electric lighting quickly because it facilitated all-night working so perhaps ironmasters were easily alerted to the possibilities of the new power. Electric motors proved to be very good for driving rolling mills where the combination of power and precise control was valuable. Thereafter electric motors were gradually introduced for driving machine tools and the advantages of individual drives over line-shaft systems were readily appreciated. The first permanent public electric railway was opened at Lichterfelde in Germany in 1881. Built by Siemens it ran for about three kilometres. Each carriage had a motor under the floor connected to the wheels through a belt drive. The first electric railway in the United Kingdom ran between Portrush and Bushmills in Ireland. Electric traction was chosen there because abundant water power was available and a hydro-electric generating station was built on the River Bush. England s first electric railway was the Volk s Railway which still runs on the sea front at Brighton. The railwaysjust mentioned were all small systems. The first really practical electric tramway system was built by Sprague in Richmond Virginia in 1888. Forty cars powered from overhead conductors ran over 20km 12.5 miles of streets. FrankJ.Sprague trained as an engineer with the US navy then set up his own electrical engineering company in 1884. His most important contribution was the multiple unit control system which made it possible to have motors distributed along the length of a train and supplied from .