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An Encyclopedia of the History of Technology part 51

An Encyclopedia of the History of Technology part 51. 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 an Act was obtained in 1885 but the Manchester Ship Canal Company had to repurchase the old Bridgewater Canal from the railways and they had difficulty in raising the capital. The target was reached with a month to spare. Work commenced in 1887 and at times 17 000 men with a great deal of novel mechanical equipment were employed on cutting the canal. Construction included the entrance locks at Eastham and four other sets of locks. Brindley s original aqueduct was replaced by the Barton Swing Aqueduct. At the Manchester end a dock system was established which became very busy with cotton and grain traffic. Through sailings started on IJanuary 1894 and the canal was formally opened on 21 May 1894. Additional docks nearer the Liverpool end were opened in 1922 and 1933 and a new Queen Elizabeth II dock for oil tankers at Eastham just below the entrance to the Ship Canal in 1954. With the decline of the cotton industry and the changing pattern of sea transport the Manchester Ship Canal also became moribund. Sir Edward Leader Williams who before becoming engineer to the Manchester Ship Canal had been engineer to the Weaver Navigation had conceived the idea of constructing a lift between the Weaver and the Trent and Mersey Canal at Anderton to overcome a difference in levels of 15m 50ft and the design by Edwin Clark was the progenitor of several lifts on the Continent. Completed in 1875 it was built as a hydraulically counterbalancing lift with two tanks supported on pistons. The cylinders in which the pistons worked were interconnected and the flow of hydraulic fluid could be started and stopped by opening and closing a valve in the connecting pipe so that the descent of one tank controlled the ascent of the other. In 1882 one cylinder burst and both cylinders were renewed but by 1905 corrosion was affecting both cylinders again and it was decided to convert the lift to two independent tanks each counterbalanced by a series of weights suspended on .