how did the U.S. start using the red/green light system for traffic lights?
where did it originate? Why did they decide to use red lights for stop, green lights for go and yellow lights for caution? How did they come up with the arrangement?
The modern traffic light has its origins in the lights used to guide railway traffic. The railroads used a semaphore system with red and green lanterns. The semaphore arm would hide one lantern or the other, giving the oncoming train a clear signal about whether or not it could procede.
The first traffic light was installed in London, England in 1868 to regulate wagon and buggy traffic. It used the same red and green signals as the railroads of the time.
With the introduction of the automobile, traffic worsened. More and more police officers were required simply to direct traffic in larger U.S. cities. The three-color traffic light was invented in Detroit, Michigan in 1920 by police officer William L. Potts, who was looking for a way to free up officers from traffic duty.
For more on the history of traffic lights, try these articles:
– from ‘The Journal of Transport History’: http://findarticles.com/p/articles/mi_qa3884/is_200609/ai_n17189350
– from ‘Michigan History Online’: http://www.michiganhistorymagazine.com/features/michweek/splash.html
– from ‘Tech Transfer Newsletter’: http://www.techtransfer.berkeley.edu/newsletter/07-4/traffic_signals.php
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someone inventred it
References :
http://en.wikipedia.org/wiki/Stoplight
Gee how did they do that? That’s an interesting question…I don’t think anybody in History can answer that question by the looks of things.
References :
The colors mean. red =blood=danger.
green=fields=pleasant=so go
yellow=sun=light=look carefully
References :
The modern traffic light has its origins in the lights used to guide railway traffic. The railroads used a semaphore system with red and green lanterns. The semaphore arm would hide one lantern or the other, giving the oncoming train a clear signal about whether or not it could procede.
The first traffic light was installed in London, England in 1868 to regulate wagon and buggy traffic. It used the same red and green signals as the railroads of the time.
With the introduction of the automobile, traffic worsened. More and more police officers were required simply to direct traffic in larger U.S. cities. The three-color traffic light was invented in Detroit, Michigan in 1920 by police officer William L. Potts, who was looking for a way to free up officers from traffic duty.
For more on the history of traffic lights, try these articles:
– from ‘The Journal of Transport History’: http://findarticles.com/p/articles/mi_qa3884/is_200609/ai_n17189350
– from ‘Michigan History Online’: http://www.michiganhistorymagazine.com/features/michweek/splash.html
– from ‘Tech Transfer Newsletter’: http://www.techtransfer.berkeley.edu/newsletter/07-4/traffic_signals.php
———-
Librarian, Ask Why Ky
http://askwhyky.org
Free 24/7 Answer Service for Kentucky
Librarians–Ask Us, We Answer!
Find your local Library at http://lists.webjunction.org/libweb/Public_main.html
References :