The world’s first traffic light was installed on December 10, 1868 outside the British Houses of Parliament in London by a railway engineer named J.P. Knight. Unfortunately the lamp, which ran on gas, exploded on January 2, 1869, either injuring or killing the policeman operating it. The modern electric traffic light was invented by Lester Wire, an American policeman, in 1912 in Salt Lake City, Utah. The design was simple, consisting of a green light for go and a red light for stop. Since then there have been other interesting ideas. … Read More