The first traffic signal was invented by a railway signaling engineer. It was installed (1) the Houses of Parliament in 1868. It (2) like any railway signal of the time, and was operated by gas. (3) , it exploded and killed a policeman, and the accident (4) further development until cars became common. (5) traffic lights are an American invention. Red-green (6) were installed in Cleveland in 1914. Three-color signals, operated (7) hand from a tower in the (8) of the street, were installed in New York in 1918. The (9) lights of this type to (10) in Britain were in London, on the junction between St. James’s Street
and Piccadilly, in 1925. Automatic signals were installed (11) year later. In the past, traffic lights were (12) . In New York, some lights had a statue on top. In Los Angeles the lights did not just (13) silently, but would ring bells to (14) the sleeping motorists of the 1930s. These are gone and have been (15) by standard models which are universally adopted.
