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Events on Thursday 10 December 1868 1
1868First traffic light installedGas-powered signal installed outside ParliamentA gas-lit revolving signal designed by railway engineer J.P. Knight was installed outside the Houses of Parliament in London to control horse-drawn traffic. It used semaphore arms by day and red and green gas lamps by night. The signal exploded weeks later after a gas leak, and traffic signals were not widely readopted until the automobile era.