The Economic Times

During the American revolution in 1776, a rebel inventor devised a daring weapon against the British Navy- a bomb-carrying submarine

Back in 1776, a clever American inventor created the Turtle, a one-man submarine shaped like an acorn. Its mission was to sneak up on enemy ships underwater and plant explosives. This early attempt to attack the HMS Eagle failed, as the submarine's basic design and propulsion weren't practical for long underwater missions then.