In 1776, this one-man vessel became the first submarine ever to be used in battle.

The American David Bushnell created the submarine and called it a "turtle" because he felt the two sides he put together resembled a turtle. It actually looked more like a walnut.

The Turtle's mission was to attach a bomb to the underside of the British ship, the HMS Eagle. However, the operator of the turtle, Ezra Lee, hit metal instead of wood when he attempted to attach the bomb to the ship with a screw. The bomb was released into the water and caused a big explosion. Although the HMS Eagle did not suffer any damages, the British considered the threat real and moved their ships, which was the result the Americans wanted.

The ideas that Bushnell had in the 1770's helped to develop the future of the submarine.