The American submarine Turtle was built in Connecticut with the direct approval of General George Washington by David Bushnell an underwater explosives expert and inventor.
The Turtle was named so because of its shape, like two turtle shells mated together. It measured just three feet wide, 10 feet long and 6 feet tall. It could accommodate one man. Navigation was via a small rudder and propulsion, up/down and forward/backward, via two hand-cranked propellers. It remained water-tight by covering the whole vehicle, mainly built out of oak, in hot tar and running tight steel bands around it.
The little sub dived by allowing water to pour into a bilge tank at the bottom of the vessel, and it could surface via pumping out that water via a hand-cranked screw pump. In case of an emergency, such as a crack occurring in the boat's hull, there was 200lbs of lead that could be released, which would allow the sub to shoot back up to the surface. There was only enough air inside Turtle for one crewman to survive for 30 minutes.
There was a series of glass port holes on the top of the Turtle where its hatch met its hull. These provided light during daytime operations and a very basic view for navigational purposes. Since she would mainly operate at night, and a flame would use oxygen, internal illumination was provided by a cork that was covered in bioluminescent fungus.
On 7 September 1776, Sergeant Ezra Lee, one of three volunteers, slowly fought his way toward the HMS Eagle, which was moored south of Manhattan Island, after being towed out a ways from shore by row boats, Lee's progress was almost non-existent until the current began carrying him toward his objective. Once within clear view of HMS Eagle, he slowly submerged and crept underneath the big ship's stern, towards its rudder area. Here begun his attempt to drill into the Eagle so that the explosive package could be attached. Lee, however, was unable to break through what seemed like an impenetrable metal barrier (later it was thought that this was the iron plating around the ship's rudder hinge system). He then tried to submerge directly underneath the Eagle but the clumsy little sub had issues with staying in one place under the big ship's curved hull and fight the currents from the river and tide.
Lee eventually gave up on the attack, and made his way back out into the Hudson channel. Lee stated that he was spotted by the British as he left, and that multiple teams of sailors rowed out to investigate the strange object in the water. Lee then released the explosive charge, which was an elaborate timed device that used a fragile flintlock ignition system, to distract the search teams. The teams gave up long before the charge went off, which Lee said resulted in a massive explosion sending water high into the air.
Another attempt was made on October 5th, when Sergeant Lee attempted to attach a similar charge to a British Frigate also anchored off of Manhattan. He claimed that he was spotted on his approach to the ship so he aborted the mission. A few days later the Turtle was sunk as it sat atop its tender vessel near New Jersey. The British saw it and engaged it without a fight, blowing it to bits, although Bushnell claimed he salvaged parts of it.