Did you know that the traffic signal was invented in 1912 as a two-color, red-and-green light designed by a Detroit policeman? Yeah, neither did we.

Check out this fun and informative article at Design Observer on the history of the device, and check out the signal patent drawing as well—something we’re sure Williamson Gallery Director Stephen Nowlin will appreciate in conjunction with the gallery’s current shows, The Future of Objects and The Curious World of Patent Models.

Read more: Red Light, Green Light : The Invention of the Traffic Signal, and check out photos of the Williamson exhibit on the gallery’s Facebook page.