Submarines
During the American Civil War, the Union-built and French-designed submarine Alligator was the first U.S. Navy submarine and the first to feature compressed air (for air supply) and an air filtration system. Initially hand-powered by oars, it was converted after 6 months to a screw propeller powered by a hand crank. With a crew of 20, it was larger than Confederate submarines. Alligator was 47 feet (14.3 m) long and about 4 feet (1.2 m) in diameter. The submarine was lost in a storm off Cape Hatteras on April 1, 1863 with no crew and under tow to its first combat deployment at Charleston.
Read more about this topic: French Weapons In The American Civil War