A Dropped Naval Spring: The Accident Behind the Slinky Toy

The workshop floor was scattered with metal parts, tools, and half-finished mechanisms. Springs of various sizes lay in shallow trays. On a cluttered bench, a torsion spring slipped from a shelf. It fell. Hit the ground. Then did something no one expected. Instead of collapsing into a tangled heap, it began to step forward. One graceful loop after another. Walking. Richard James watched the motion in silence. What he had just witnessed was not a toy. It was a mechanical curiosity. And within a few years, it would be bouncing down staircases in homes around the world. A Naval Engineering Problem In the early 1940s, Richard James worked as a mechanical engineer at the U.S. Navy’s Bureau of Ships. His…