Did you know that the first submarine was powered by just one man?

The first submarine to go into action was an American vessel called the Turtle. It tried to attack a British warship in 1776, during the American War of Independence. The Turtle was an egg-shaped craft powered by one man, who sat inside and turned two handles connected to screw propellers outside.

Manned by Sergeant Ezra Lee, the Turtle’s mission was to attach a mine to the warship’s hull. The submarine worked well, but the bottom of the ship was lined with metal, Preventing Sargent Lee from fixing the mine.