ADMICRO

Choose the best answer:
The first traffic signal was invented by a railway signaling engineer. It was installed outside the Houses of Parliament in 1868. It (1) ______ like any railway signal of the time, and was operated by gas. (2) ______, it exploded and killed a policeman, and the accident (3) ______further development until cars became common.(4) ______traffic lights are an American invention. Red-green systems was installed in Cleveland in 1914. Three-colour signals, operated (5) ______ hand from tower in the (6) ______ of the street, were installed in New York in 1918. The first lights of this type to (7) ______ in Britain were in London, on the junction between St. James‘s Street and Piccadilly, in 1925. Automatic signals were installed (8) ______year later. In the past, traffic lights were special. In New York, some lights had a statue on top. In Los Angeles the lights did not just (9) ______ silently, but would ring bells to (10) ______the sleeping motorists of the 1930s. These are gone and have been replaced by standard models which are universally adopted

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