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The London Underground


The London Underground



An underground is an electrically operated underground railroad. It s construction was first stimulated in the 19th century. The world’s first underground was the brainchild of Charles Person, solicitor of the city of London. The first phase between Farrington to Paddington was begun in 1860 and completed in 1863. The construction was done in the cut and cover method. An arched brick structure was first constructed in an open trench and then earth was backfilled over it. The locomotive power for the trains being supplied by steam, the underground then had a sulphurous atmosphere. In spite of that, the subway attracted about 10 million passengers in its first year of operation. Its primary success encouraged additional construction in 1886. Instead of the old cut and cover method, this time a new construction device was used. James Henry Greathead developed a steel made cylindrical tube which could be forced forward into the ground by means of hydraulic jacks. This method made it possible to dig tunnels deep enough not to disturb surface building and traffic. The depth of the tunnels then necessitated the installation of lifts at the stations. Electrification of the lines made it possible. Later on, lifts were replaced by escalators. With the use of electricity, great expansion took place and by the early 1970s London had 102 miles of underground lines, the second largest in the world. The largest underground is now in New York. The increasing automobile congestion in metropolitan cities has spurred the building of new underground or subway systems in other cities too.

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