H. L. Hunley was a submarine of the Confederate States of America that played a small part in the American Civil War, but a large role in the history of naval warfare. It sank on October 15, 1863, killing all eight of her second crew, including Horace Hunley himself, who was aboard at the time, even though he was not enlisted in the Confederate armed forces. Read more
It's long been a mystery why the H.L. Hunley never returned after becoming the first submarine in history to sink an enemy warship in 1864, but new research announced Friday may lend credence to one of the theories. Scientists found the eight-man crew of the hand-cranked Confederate submarine had not set the pump to remove water from the crew compartment, which might indicate it was not being flooded. That could mean crew members suffocated as they used up air, perhaps while waiting for the tide to turn and the current to help take them back to land.