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Green Red
How did the U.S. using red and green light for traffic system?
What is the source? Why did they decide to use red lights for stop, green lights to go and yellow caution lights? How did the arrangement?
"Even during the horse and buggy days, traffic in big cities was often heavy. Police officers had to be stationed full time directing traffic at busy intersections. The first light saw the light before the car was in use and the traffic consisted only of pedestrians, strollers, and wagons. Installed at an intersection in London in 1868, was a revolving lantern with red and green signals. Red means "stop" and green means "caution." The lantern, illuminated by gas, developed by means of a lever at its base to the right light before the traffic. On 2 January 1869, this light oil exploded, injuring the policeman who was operating. With the advent of automobiles, the situation became even worse. Police Officer William L. Pots of Detroit, Michigan, decided to do something about the problem. What he had in mind was how to adapt the railroad signals for street use. The railroads were already using controls automatic. However, rail traffic traveled along parallel lines. Street traffic travels at right angles. Potts used red, amber, green and the lights of the railway and about thirty-seven dollars of the wire and electrical controls to make the first three-way 4-color traffic light. Installed in 1920 at the corner of Woodward and Michigan Avenues in Detroit. Within a year, Detroit had installed a total of fifteen of the new automatic lights. At about the same time, Garrett Morgan of Cleveland, Ohio realized the need to control the flow of traffic. A gifted inventor and reportedly the first African American to own a car in Cleveland, Ohio, invented the electric automatic traffic light. Although it was more like semaphore signals you see at railway crossings today. Many others had obtained U.S. Patents for traffic signals, some as early as 1918. But Morgan's patent was purchased by General Electric Corporation and provided that the protection they need to start building a monopoly on the manufacture of light traffic. " 1. As for the color red, I remember reading about the studies for almost 100 years that is bright red color that the first register on our nerve endings in the retina. Therefore, for people no color blindness, bright red catches the eye faster – hence its traditional use as the universal color of fire, traffic safety lights, danger, perhaps. "
