http://www.squidoo.com/traffic-signals
Traffic lights were used previous to cars came onto the roads. They were invented in 1868 by British railroad signal engineer, JP Knight who created a lantern with Red and Green signals. This was mounted in from of the British House of Commons to control the flow of Horse Buggies as well as pedestrians.
http://www.squidoo.com/traffic-signals
See this Amp at http://amplify.com/u/a12wdw
Comments