The Traffic Light

The most vital aspect of transportation today is that one arrives at their destination safely and securely. Because of this, we rely on the safety features of the road, the most prominent of which is the traffic light, which was invented in 1920 by Detroit police officer William L. Potts.
Even before automobiles became popular, or were even invented, police officers had to be stationed at almost every major intersection to make sure horse-drawn buggies weren’t “kissing at the crossroads”. Back in the late 1860s, the first ancestor of the modern traffic light was made and installed in London, and it had red and green signals for pedestrians, wagons and buggies. However, it was a gas-powered light, operated by hand, and less than a year after it was set up, it exploded and injured the police officer that was operating it. Obviously, the traffic light needed some improvements.
The idea for William Potts’ traffic light design from train signals, which seemed to be very effective in preventing accidents on the railroad. There was a problem, though: train signals were made for tracks in parallel lines, while intersections came from four different directions at right angles. Potts’ prototype traffic light was comprised of twelve railroad lights, four each of red, amber and green, wood and tin for the shell, and $37 worth of electrical wire. With these materials, he assembled the first-ever four-way, three-colour traffic light. In contrast with traffic signals made in the past, Potts’ included the third colour, amber, to warn drivers that the light was going to turn red, so there wouldn’t be as many surprises on the road. The traffic light was installed at the corner of Woodward and Michigan Avenues in October of 1920. The manually-operated signal was effective; within a year, there were 15 of Potts’ traffic signals at the busier intersections in Detroit.
Potts was not alone in his attempts to handle the big issue of traffic problems. In Cleveland at around the same time, a man named Garrett Morgan came up with a similar idea for controlling the flow of traffic. He created a traffic light of his own, which was more akin to train signals in design than Potts’. However, Morgan’s invention was automatic, meaning that police officers wouldn’t need to man each intersection, and Morgan patented his invention. The patent was later bought by the General Electric Corporation. This allowed them to begin manufacturing traffic lights commercially.
Since then, traffic lights have obviously become essential to transportation all over the world. Without the innovations of both William Potts, inventor of the four-way, tri-colour traffic light, and Garrett Morgan, the inventor of the first patented and commercially manufactured traffic signal, matters of safety on the road would be drastically different than they are today.