33 Inventions That Started as a Mistake But Turned Out to Be Life-Changing

It actually makes sense that the slinky, a toy that is basically a spring, was an accident. In 1943, Richard James, a naval mechanical engineer, was working on creating springs to protect navy instruments when he accidentally knocked a spring off a shelf. The spring displayed an ability to ‘walk’ across objects and reassemble itself upright on the floor.

James dedicated a year to refining his prototypes to perfect the balance between steel’s properties and wire tension. With a modest $500 loan, Richard and his wife Betty founded James Industries. Their persistence bore fruit when the first batch of 400 Slinkys was quickly snapped up in 90 minutes upon release in the mid-1940s.