The first traffic lights anywhere in the world sprang into action outside the House of Parliament on 9 December 1868. The robot-like contraption shown above was installed in the north-east corner of Parliament Square — near the spot that is today occupied by the statue of Winston Churchill.
Red, green and semaphore
The signal system was designed to bring order to a chaotic junction. In the months before its installation, two MPs had been badly injured and a traffic policeman killed at this spot.
The traffic lights towered six metres (20 feet) above the carriageway. They still required a police operator, but were much more visible.
The equipment worked along similar principles to those already used on the railways. Right from the start, it operated on a red/green light system.
The power came from gas. Gas lights can be difficult to see during the daytime, and so semaphore paddles were added to the top. When lowered to 45 degrees, as in the picture, traffic is free to flow with caution. When raised, the traffic should stop to allow pedestrians to cross.
A dreadful portent
The traffic lights had some initial success. 'The regular town drivers are fairly, and to quite an unexpected extent, amenable to the signals,' thought the Illustrated Times, soon after the lights were installed.
Others were more skeptical. One commentator, on approaching the 'Dreadful Portent' from Westminster Bridge, asked his driver what it was. 'Another o' them fakements put up to wex the poor cabbies,' came the reply.
Punch magazine also likened the traffic post to a scary apparition, beaming through the fog:
Appearances aside, these early traffic lights were simply not good enough. Many drivers did not understand what the angled semaphore blades were supposed to indicate. Others ignored them. The technology often broke down. In January 1869, a gas leak caused an explosion at the base of the semaphore, badly burning the face of the police operator.
The lights lingered on for a few more months, but constant breakdowns and general ineffectiveness led to their removal by the end of the year. Traffic lights did not return to the capital until 1926, when a manually operated series of electric lights was installed along Piccadilly.