Who invented traffic lights and where were the first ones situated?
• THE FIRST traffic signal was invented by J P Knight, a railway signalling engineer. It was installed outside the Houses of Parliament in 1868 and looked like any railway signal of the time, with waving semaphore arms and red-green lamps, operated by gas, for night use. Unfortunately it exploded, killing a policeman. The accident discouraged further development until the era of the internal combustion engine. Modern traffic lights are an American invention. Red-green systems were installed in Cleveland in 1914. Three-colour signals, operated manually from a tower in the middle of the street, were installed in New York in 1918. The first lights of this type to appear in Britain were in London, on the junction between St James’s Street and Piccadilly, in 1925. They were operated manually by policemen using switches. Automatic signals, working on a time interval, were installed in Wolverhampton, in 1926. The first vehicle-actuated signals in Britain occurred on the junction between Grace
