¶No copies recorded on Copac or OCLC. A wonderful and rare illustrated broadside alerting the public to the very first traffic signal which was installed outside Westminster on October 9th, 1868. In 1866, over 1,000 people were killed on London Roads with a thousand more injured by the horse-drawn traffic. Designed by John Peake Knight, 1828-1886, a railway engineer and inventor, the signals used a semaphore system (based on railway signalling) during the day and green and red gas lamps at night. Standing over six metres high, the signal was operated manually by a policeman. On seeing the "CAUTION" sign (green), 'all persons in charge of Vehicles and Horses are warned to pass over the Crossing with care, and due regard to the safety of Foot Passengers. The signal "STOP", will only be displayed when it is necessary that Vehicles and Horses shall be actually stopped on each side of the crossing to allow the passage of Persons on Foot...' Knight's invention was very short-lived. On January 2nd, 1869, a gas leak caused an explosion which injured the police operator and caused the system to be removed from use. A similar traffic control system was not put in place again until 1894 when gas lights and semaphore were installed to control both river and highway traffic at Tower Bridge. Illuminated traffic signals only became commonplace with the first electric lights being developed in 1912 by the appropriately named Lester Wire, a policeman in Salt Lake City, Utah.