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The story of the American traffic light starts with a Detroit police officer more than 100 years ago

America 250: The story of the American traffic light starts with a Detroit police officer more than 100 years ago
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(WXYZ) — Some of the everyday technology we see across our country was invented right here in Detroit, including the traffic lights drivers use every single day in America.

We see traffic lights every day, and most of the time, we think nothing of it. But the story of the traffic light starts with a Detroit police officer more than 100 years ago.

Watch Ali Hoxie's report below

America 250: The story of the American traffic light starts with a Detroit police officer more than 100 years ago

We all know the meaning of traffic lights, but rarely do we think of it's backstory.

“Did you know that the first tri-colored light in America was installed right at this intersection?” I said to Stephanie Kaiser while we spoke in Detroit.

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“Really? No. I didn’t, tell me more," she replied.

On December 20th, 1920, the first tri-colored light was installed in the heart of downtown Detroit, at the intersection of Woodward and Fort.

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“I didn’t know that. That’s new news to me," said Roseville resident Sheila Clemente.

And if you're a history buff, you can see the light that started it all inside the Henry Ford Museum in Dearborn.

Matt Anderson is the Curator of Transportation at the museum.

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“This light was invented by a fella named William L. Potts, who was the head of traffic signaling for the Detroit Police Department," Anderson said. “Before the traffic lights the only way to control traffic was either to have an officer physically standing in the intersection with a whistle or maybe a flag or some kind of a hand signal or up in a tower, manually controlling a semi-floor signal or lights, it was a lot of risk to the officer, but also a lot of labor involved.”

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A photo of the first traffic light from the Henry Ford Museum
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The police officer who helped install the first tri-color traffic light in America, right here in Detroit

And while there had been experiments using colored traffic lights at the time, it was Potts who incorporated the yellow light, warning drivers to get ready to slow down.

“That caution light is so important, because it lets you know that the red light is coming, so you don’t have to slam on the brakes and stop right on a dime, and it creates a safer intersections in all directions. If you have the red light come on right away and then the green light simultaneously, you’re going to have some overlap which could be very dangerous and led to a potential collision," Anderson said.

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The first tri-color traffic light

This wooden box, covered in tin and built in a basement workroom, has come a long way in Detroit and across our country.

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“It’s something for the kids to grow up to see and learn from," said Detroiter Sandy Sullivan.

If you would like to see this traffic light for yourself, it's at the Henry Ford Museum in the "Driver America" section.

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