The Turtle was the world's first military submarine. Designed by John Bushwell and built in 1775, it was designed for use in the Patriot military. This was the time when the colonists and the British were not at friendly terms.
Sargent Ezra Lee drove the submarine, in hopes of attaching explosives to British ships. All of these attempts failed, and the submarine eventually was sunk by the British.
The plan was great, but the ships' hulls were covered in copper, making it impossible to drill holes. Sgt. Lee could not find a way to attach the explosives, and the mission was a failure.
The submarine had a hand crank to turn a propeller, and a foot pedal to turn a tiller. The cranking was hard and tiring, and was by no means efficient. The craft was shaped like a clam, but also resembled a turtle. It was ten feet long, three feet wide, and six feet tall. It could travel at a speed of 3 mph in still water.