Setting the record straight
stories by Frank Stephenson
Much of what people believed about the Hunley turned out to be flat wrong, according to the project team. She was not, for one thing, a crude contraption built like a glorified boiler. She was a marvel of engineering and a warship ahead of her time. Here’s a summary of some key discoveries so far:
Key findings about the vessel itself
- The vessel carried eight crewmen instead of nine, as records and testimony had indicated.
- The vessel’s true dimensions were established: length over all: forty-two feet beam: forty-two inches distance between conning towers: sixteen feet
- The vessel may not have been built from the scraps of old boilers, as was previously thought, because the hull reveals exceptional design and engineering skill employing abutting plates (as opposed to overlapping plates, the standard in boiler construction of the period) riveted to a series of backing straps on the inside.
- All rivets (thousands of them) are sunk or hammered flush to the outside, an obvious means of reducing drag.
- The crankshaft was not connected directly to the propeller but was instead offset to starboard and tied into a system of reduction (differential) gears (ratio still unknown) and a large flywheel. This helped sustain the crankshaft’s rotation and propeller’s momentum.
- A wooden bench for the crew was discovered mounted on the port side. This painted bench, measuring twelve inches wide and eighteen feet long, is made of pine.
- The design of the vessel’s propulsion system reveals the secret of how engineers solved the problem of balancing the craft with seven crewmen sitting on the same side (the port). The cramped interior forced the crewmen to hunch over the crankshaft, thereby putting their collective center of gravity amidships.
- To date, no evidence has been found that definitely establishes how the vessel’s weapon system was either constructed or deployed. The spar was attached by a bolt that was easily removed, allowing the spar to be raised separately.
- The vessel’s plumbing system is ingeniously designed. Two pumps in the sub were found to have triple functions. They served as ballast pumps (to add or remove seawater) and as bilge pumps. By the twist of a valve, either pump could control the water level in either of two ballast tanks.
- Nine discovered valves controlled the vessel’s network of pipes attached to two ballast pumps. Because of obscurity from concretion, the team has not yet determined the exact position of all valves.
- The inside of the vessel was painted white, possibly to magnify any illumination.
- The dive planes were connected to a dive-plane control rod that is not attached to their centers. A dive-plane control handle was counterbalanced to help move the large dive planes and thus make it easier to control the vessel during descent and ascent.
- The captain used a joystick-like lever to control the rudder, not a wheel as was previously thought.
- Two large holes, both on the starboard side, occurred long after the vessel sank and most likely were the result of corrosion and erosion.
- The hatches of both conning towers reveal fittings that include brass valves for equalizing internal air pressure. No historical records of this feature on the vessel exist.
- Researchers found a total of eighteen glass ports in the hull, including ten “deadlights” for admitting sunlight or moonlight into the dark interior while running on the surface. The other ports were mainly for navigational viewing from the conning towers.
- The vessel was composed of at least two different kinds of wrought iron as well as various cast iron parts. The narrow bow and stern sections, along with both conning towers and their hatch covers, are made of cast iron, whereas the hull is made entirely from wrought iron. Construction materials included wrought iron, cast iron, brass, copper, glass, wood, and rubber (for watertight gaskets).
- The vessel’s forward hatch was unlocked and partially open. The aft hatch was securely locked.
- The vessel is equipped with a series of contoured iron blocks that form its keel. These blocks are secured to the vessel by T-shaped bolts, three of which could be undone by crewmen in emergencies. No evidence was found indicating that any effort was made to drop these blocks.
- A single “bull’s-eye” whale-oil-burning lantern contains a clear lens, with no evidence of any artifice that would have given the lantern’s light a blue tint.
- Because of concretion on the outer skin, there’s no evidence the sub had a lanyard reel, which was previously thought to be the device used in detonating the vessel’s torpedo from afar.
- Loose pieces of pig iron ballast were found on the floor of the vessel, most of which were iron plates that originally may have been used for building ironclads.
- All evidence suggests that the vessel rapidly filled with water upon sinking, although there may have been air pockets trapped inside the hull.
Key findings about the crew
- All eight crewmembers died at their stations, with no evidence of panicked escape attempts.
- The sediment that eventually entered and filled the interior did so from the bow first, as evidenced by the fact that Lt. Dixon (the ship’s captain whose station was at the bow) was buried first.
- Fingerprints from a crewmember were imprinted into the concretion inside the hull.
- The insides of a shoe revealed the impression of skin atop a heel section.
- Shreds of various fabrics included pieces of leather, silk, cotton, wool, and cashmere.
- Remains found include bone, teeth, hair, and remnants of brain tissue.
- Personal or ship artifacts found and preserved include the captain’s pocket watch, his legendary twenty-dollar gold piece, his gold diamond ring and diamond brooch, his binoculars, a brass compass, the broken remains of a glass depth gauge, various buttons and buckles, a medicine bottle, an identification (“dog”) tag from a Union soldier, four smoking pipes, two pocketknives, seventeen canteens, and assorted wooden toothpicks and matchsticks. No sidearms or other weapons were discovered.