In 1812, inventor Charles Redheffer caused a sensation in Philadelphia when he announced a perpetual motion machine. Residents could view the device for a fee, he said, but none could approach it lest they damage the apparatus. When city commissioner Nathan Sellers arrived to observe the device, he happened to bring his son Coleman, who noticed something that all the adults had missed: The machine’s cogs were worn on the wrong side. The device that the machine was ostensibly driving was itself impelling the whole apparatus.

Redheffer decamped to New York City and tried again with an altered machine, but Robert Fulton noticed that this one ran unsteadily. He traced a catgut cord to an upper room, where an old man was turning a hand crank. Spectators destroyed the machine, and Redheffer fled the city.