The H.L. Hunley, the world’s first successful combat submarine was covered in concretion when raised from the ocean floor in 2000. Scientists worked for years removing the layer of sand, sediment, shells and corrosion to preserve the Confederate vessel.
Last year, scientists at the Warren Lasch Conservation Center in North Charleston finished cleaning the exterior of the vessel and began cleaning the interior.
Recently, scientists recovered a tooth stuck to one of the crank handles in the Hunley. They think the tooth belonged to crewmember Frank Miller, who most likely lost the tooth after his death shortly after the Hunley sank the Housatonic in Charleston Harbor during a night time attack on Feb. 17, 1864.