Hunley scientists find valve used for filling sub's rear ballast tank


Wednesday, March 21, 2001

Of The Post and Courier staff


     Hunley archaeologists have found one of the controls they believe will help tell the story of what happened in the Confederate submarine's final moments.
     Scientists on Tuesday identified the valve used to fill the sub's aft ballast tank, called the seacock. Whether the valve is open will tell if the Hunley crew was trying to surface when the submarine disappeared after sinking the Union sloop Housatonic on Feb. 17, 1864.
     As usual, though, the Hunley is reluctant to give up its secrets. The valve and attached piping are covered with concretion similar to that on the hull's exterior.
     "We can see most of what looks like pumps and valves, but we can't see enough to tell whether it's open or closed," project manager Bob Neyland said. "The pump must be farther back."
     Here's how it worked: The Hunley floated on the surface until its fore and aft sea cocks were opened, letting water into its two ballast tanks. That water would serve as the weight needed to submerge the sub. When the crew had as much water as they wanted in the tanks, they closed the valves. To expel the water, they used pumps, one for each ballast tank.
     The valve identified Tuesday is nearly under the sub's aft hatch. Farther up in the crew compartment, scientists believe they have found the first signs of the hand crank that eight of the nine crew members turned to power the submarine's propeller.
     Neyland said there are a couple of bumps in fudge-like mud packed in the sub's interior that could be first signs of the hand cranks. Although some historical accounts differ, most people said the crew sat on the sub's port side and the crank was attached on the starboard side. Scientists have been expecting to find the crank any day.
     They soon may get a better idea of what's coming up in the excavation when they X-ray the crew compartment. The team tried that before the excavation began, but the sediment was too tight for the X-rays to penetrate.
     Scientists are also still debating whether to remove another panel on the top of the submarine. So far they have removed three hull plates to gain access to the Hunley's interior. Now, to better reach the forward controls - where they expect to find the highest concentration of artifacts - they want to remove the hull plate just aft of the forward conning tower. The rub is that that plate holds the stuffing box for the sub's snorkels, and scientists don't want to remove the plate if there is any danger of damaging that mysterious piece of the sub's equipment.
     As the team gets deeper into the sub, the discoveries are coming almost daily. Last week, they found two buttons from a crewman's jacket and the bench the crew sat on. Earlier this week, they found a medicine bottle and a shelf.

Used with permission of The Post and Courier and Charleston.Net

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