J. P. Knight

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J. P. Knight
Born (1828-12-13)13 December 1828
Died 23 July 1886(1886-07-23) (aged 58)
Nationality British
Education Nottingham High School
Spouse(s) Elizabeth Knight (m. 1832–1913)
Children James Percy KNIGHT
Engineering career
Employer(s) London, Brighton & South Coast Railway
Significant projects first traffic light
Significant awards Legion of Honour, 1878[1]

John Peake Knight (1828–1886) was a railway engineer and inventor, credited with inventing the first traffic light.


John Peake Knight was born in Nottingham and attended Nottingham High School. He left school at 12 to work in the parcel room of Derby railway station. Peake Knight was promoted quickly and by the age of 20 was Traffic Manager for the London to Brighton Line. He did a great deal to improve the quality of railway travel, introducing the Pullman car and safe carriages with alarm pulls for ladies.

He and his wife,Elizabeth had five sons and the eldest founded J P Knight Ltd, tug boat operators.

Peake Knight died in 1886 and the Prince of Wales had a special wreath placed on his coffin during the funeral.[2] He is buried in Brompton Cemetery in London.[3]

Invention of traffic lights[edit]

John Peake Knight is credited with inventing the original traffic light in 1868, a semaphore system based on railway signalling. In 1866, a year in which 1102 people were killed and 1334 injured on roads in London, he proposed a signalling system to regulate the horse-drawn traffic and reduce the number of road accidents.

This was not the traffic light we know today, but was a revolving gas-powered lantern with a red and a green light at the end of a wooden arm. Knight's invention was similar to the railway signals of the time. The traffic light was originally installed on December 9,1868, near London's House of Commons, at the intersection of Great George Street and Bridge Street, London SW1.[4] However, the lights exploded during use in 1869 because of a gas leak and were removed by 1870. A policeman nearby on points duty was badly injured.

In 1910, Ernest Sirrine of Chicago improved the light by adding automatics. He also changed the red and green lights to words that read proceed and stop.

In 1912 Lester Wire, a detective in Salt Lake City, Utah, opted to go back to red and green lights and is credited with inventing traffic lights as we know them today. However, this time, electric lights developed in the USA were used instead of the original gas-powered lanterns.

In 1922, Garrett Morgan had witnessed a serious accident at an intersection in Chicago and invented a traffic control device and applied for a patent on it in 1922.[5] His invention was a hand-cranked mechanical sign system using signs that could be switched relatively easily by a traffic control officer.[5] His device was relatively simple, yet had key additional safety features that many others at the time did not have. In addition to having "stop" and "go" indicators, it had an "all stop" signal that could be used to clear the intersection to allow pedestrians to cross or to stop cross-traffic before signaling a different direction to proceed. It also had a "half mast" warning position to indicate general caution at times when the device operator was not present.[8] In addition to the signs, his device featured lights and warning bells powered by a battery or a connection to a main power source.[5]

A memorial plaque to Peake Knight's invention can be seen at 12 Bridge Street, Westminster, the corner building close to where the original traffic lights were erected. Minister for Roads and Road Safety Baroness Hayman unveiled the plaque on 4 March 1998.[2]


  1. ^ Day, Lance; Ian McNeil (1996). Biographical dictionary of the history of technology. Taylor & Francis. p. 404. ISBN 0-415-06042-7. 
  2. ^ a b City of Westminster green plaques
  3. ^ Carnell, Jennifer (22 September 2009). "Photographs of Brompton Cemetery in London by Jennifer Carnell. Victorian graves of famous and not so famous people, including the novelist G.A. Henty". Retrieved 2009-11-08. 
  4. ^ "The man who gave us traffic lights". BBC. 16 July 2009. Retrieved 2011-04-25. 
  5. ^ a b c "An American Inventor" Federal Highway Administration

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