In 1864 the Hunley rammed a spar charge into the Union blockade ship the USS Housatonic and sunk her. The Hunley never made it back to shore and much speculation was done as to what happened to it.
Scientists had hoped that by cleaning the hull they would find evidence of what may have happened, but other than a couple dents on the hull, there appeared to be no damage. It remains a mystery.
The conservation team has removed about 1,200 pounds of sediment and debris from the outside hull of the Hunley, and will shortly begin a year long process of cleaning the inside. They are hopeful they will uncover additional clues as to what happened after sinking the USS Housatonic.