Red Light Means... Stop and Remember When It Didn't

Those new fangled traffic lights are quite a marvel, aren't they? At least they were 75 years ago.

Back then, Jam Handy was to instructional films what Walt Disney was to early animation. In 1937, Chevrolet hired Handy to produce a short film explaining "automated signal lights." The devices were just in their second decade of use, and there was still astounding variation from place to place. "Even now," the film's narrator said, "traffic engineers are working with safety councils toward a national standardization of the traffic signal system."

I found Handy's nine-minute movie in the Prelinger Archive after a friend shared a link to an edited version posted by The Atlantic. For me it was yet another reminder that most commonplace technologies -- the once-complicated tools we now use almost absentmindedly everyday -- were once disruptive and confounding, too. As Atlantic Cities editor Sommer Mathis puts it:

"It's easy to forget that at one point in our history, there was no national standard that red meant stop, and green meant go -— many cities operated their own unique versions of automated traffic signals, some with four colors, and others with only two."

Actually the use of red and green signal lights pre-dated traffic lights. Credit for adapting the color-coded signal system used by railroads for automated traffic management goes to William L. Potts, an inventive Detroit police inspector who also gets credit for another innovation: the first police car equipped with an experimental radio.

Will wonders never cease!