More human remains, clues found in Civil War submarine’s conservation

More clues of the H.L. Hunley mystery are being revealed during conservation of the American Civil War submarine.

On Wednesday, researchers in a North Charleston, South Carolina, laboratory unveiled the crew compartment – which had been sealed by more than a century of ocean exposure and encrusted sediment.

“It’s that ‘wow’ moment when you step back and realize what you’re doing,” Johanna Rivera, one of the conservators, told CNN affiliate WCIV-TV in Charleston.

The Confederate Navy’s Hunley was the first submarine to sink a ship in battle, sending the USS Housatonic to the ocean floor in February 1864. Five members of the Union vessel died; 150 others were rescued. But the Hunley also went down, with all eight crew members perishing.

The conservation work, which started after the Hunley was raised in 2000, has finally exposed the sub’s entire crankshaft – used to propel the vessel by hand.

A tooth was found embedded in sediment on one of the crank handles. Officials said it wound up there “postmortem” after decomposition of one of the crew members.

Inside, they also found remnants of textiles and a thin metal wrap around the hand crank – showing how the crew operated the sub.

“When you’re turning an iron bar in front of you, or below you, you’re going to need something to keep your hands from chafing or rubbing them raw,” archaeologist Michael Scafuri told WCIV.

The new findings give insight into how the submarine was operated, but the biggest mystery is still unsolved – why did it sink after its successful, bold attack? An archaeological report issued earlier this year laid out six possible scenarios; a combination of factors may have doomed the innovative submarine.

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courtesy friends of the Hunley

Since 2000, scientists, historians and a genealogist have studied the first submarine to sink an enemy vessel. The H.L. Hunley did just that more than 150 years ago, on February 17, 1864, during the American Civil War.

courtesy friends of the Hunley

The 40-foot submarine was brought up amid much fanfare off Charleston, South Carolina, in August 2000. Author Clive Cussler and a team discovered the Hunley five years earlier, buried in the sand more than 100 yards beyond its target, the USS Housatonic.

courtesy friends of the Hunley

Conservators later began a new process -- filling the tank that holds the Hunley with chemicals that helped strip away what is called "concretion": organic material that has coated the hull and interior.

courtesy friends of the Hunley

Visitors to a laboratory and exhibit hall in North Charleston, South Carolina, can gaze down on the Hunley on weekends. The large tank is empty when scientists in the Hunley Project are at work.

courtesy friends of the Hunley

The hull is in pretty good shape, despite exposure to sea currents and elements for decades. The eight-member Confederate crew, sitting on the port side, turned a propeller by hand.

courtesy friends of the Hunley

Several years ago, then-senior archaeologist Maria Jacobsen found a gold coin that belonged to submarine commander Lt. George Dixon.

courtesy friends of the Hunley

Lt. George Dixon, according to legend, received this coin as a good-luck charm from his beloved, said to be from Mobile, Alabama. It was bent by a bullet when he was wounded at the Battle of Shiloh, two years before the Hunley made history. He had it engraved and carried it the rest of his life. It was found with his remains by Hunley Project scientists.

courtesy friends of the Hunley

Paul Mardikian, left, senior conservator, and Philippe de Vivies remove material from a piece of the submarine.

courtesy friends of the Hunley

One of the personal belongings found inside the Hunley, a watch belonging to Lt. George Dixon.

courtesy friends of the Hunley

A wallet found in the shipwreck helps tells the story of ordinary life onshore.

courtesy friends of the Hunley

Crew member James Wicks' bandana after conservation.

courtesy friends of the Hunley

This burnt matchstick was found buried in the sediment-filled interior of the H.L. Hunley.

courtesy friends of the Hunley

Experts believe this lantern was used as a flashlight by the submarine's commander.

courtesy friends of the Hunley

This conserved oil can almost looks good as new.

courtesy friends of the Hunley

The bowl of a pipe belonging to Confederate sailor Joseph Ridgaway, the only crew member positively identified through DNA.

courtesy friends of the hunley

Experts examine a shoe found in the H.L. Hunley.

One scenario holds that the Hunley was swamped by or struck by a Union vessel. Or that it plunged to the seafloor to avoid detection and never made it back up. A latch on the forward conning tower was found to be ajar.

The Hunley’s “torpedo” was attached to a spar. The crew embedded it in the Housatonic’s hull, and the charge was detonated. It’s possible the sub’s hull was breached by the explosion or the men were rendered unconscious at some point.

Nearly all of the human remains were found where the men were at their stations, rather than jammed together at an escape hatch. The remains were buried in 2004.

Work on the Hunley will continue for at least another five to seven years.

Conservators have concentrated on painstakingly removing the sediment – or concretion – that was firmly attached to the Hunley’s exterior and cramped interior.

After the process is finished, the submarine will be moved to a museum for display, though details have not been worked out.

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CNN’s Christine Sever contributed to this report.