Invention: Hand-powered submarine Country: United States Died: 1863 Horace Lawson Hunley was an early developer of hand-powered submarines, designed for use during the American Civil War. After a series of failures and underpowered vehicles, Hunley finally saw the construction of his dream, a working hand-powered submarine that was later named the H. L. Hunley. During early testing of the H. L. Hunley, it became swamped by the wake of a large ship, causing water to flood through some open hatches and resulting in the deaths of five crewmen. A later routine exercise also saw disaster on the submarine, this time sinking with Hunley himself on board. All seven crew members and Hunley himself were killed in the incident. If Hunley had survived, he would have lived to be proud of his invention though. Despite the disastrous record of the H.L. Hunley, it was later raised and became the first submarine to sink an enemy vessel in naval history.