Sunken Civil War sub reveals new clues

Scientists say a pole on the front of the Confederate submarine H.L. Hunley designed to plant explosives on enemy ships may hold a key clue to its sinking during the Civil War.

FILE - The Confederate submarine H.L. Hunley sits in a conservation tank after a steel truss that had surrounded it was removed in this Jan. 12, 2012 file photo taken at a conservation lab in North Charleston, S.C. Scientists say a pole on the front of the Confederate submarine H.L. Hunley designed to plant explosives on enemy ships may hold a key clue to its sinking during the Civil War. The experts are to release their findings Monday Jan. 28, 2013 at the North Charleston lab where the hand-cranked sub is being preserved and studied. (AP Photo/Bruce Smith, File)

FILE - The Confederate submarine H.L. Hunley sits in a conservation tank after a steel truss that had surrounded it was removed in this Jan. 12, 2012 file photo taken at a conservation lab in North Charleston, S.C. Scientists say a pole on the front of the Confederate submarine H.L. Hunley designed to plant explosives on enemy ships may hold a key clue to its sinking during the Civil War. The experts are to release their findings Monday Jan. 28, 2013 at the North Charleston lab where the hand-cranked sub is being preserved and studied. (AP Photo/Bruce Smith, File)

FILE - In this Aug. 3, 2010 file photo, the spar of the Confederate submarine H.L. Hunley is displayed at the conservation lab in North Charleston, S.C., where the submarine is being conserved. Scientists say a pole on the front of the Confederate submarine H.L. Hunley designed to plant explosives on enemy ships may hold a key clue to its sinking during the Civil War. The experts are to release their findings Monday Jan. 28, 2013 at a North Charleston lab where the hand-cranked sub is being preserved and studied. (AP Photo/Bruce Smith)

FILE - In this Aug. 3, 2010 file photo, the spar of the Confederate submarine H.L. Hunley is displayed at the conservation lab in North Charleston, S.C., where the submarine is being conserved. Scientists say a pole on the front of the Confederate submarine H.L. Hunley designed to plant explosives on enemy ships may hold a key clue to its sinking during the Civil War. The experts are to release their findings Monday Jan. 28, 2013 at a North Charleston lab where the hand-cranked sub is being preserved and studied. (AP Photo/Bruce Smith)