Scientist glimpse sub's propeller shaft
Thursday, January 25, 2001
By BRIAN HICKS
Of The Post and Courier staff
Scientists excavating the Hunley's interior on Wednesday got
their first look at the Confederate submarine's propeller shaft.
Sure enough, it's a metal bar.
Archaeologists removed another couple of buckets full of sediment
from the hole in the submarine's starboard stern and Dr. Scott Harris, a scientist from
Coastal Carolina checked out the layers of silt inside to see if it told anything about
how long it took the submarine to sink into the sea bed.
Dr. Bob Neyland, the project manager, said that after all this
time, it's exciting to now be getting a first glimpse of the inside of the submarine that
has held its secrets for 137 years.
"It's pretty amazing to be at this point," Neyland
said. "Looking in here raises questions about its construction. Did they have access
to this area or was it sealed once the sub was built? And is this part of the ballast tank
or is that tank forward of this area?"
Right now, the interior excavation is confined to the aftmost
compartment of the sub. Scientists expect to have all the sediment out of that area within
the week. Then they will use fiber optics to take a peek forward. That should help them
determine if they are in the rear ballast tank.
With part of the rear hole in the sub cleaned out, scientists can
see the shaft that turned the propeller and another one mounted along the top of the
submarine that, somehow, controlled the rudder. That bar, which could contain smaller rods
inside, is about four inches wide. No sightings, yet, of rivets or anything else that
might supply a hint of how the Hunley was built. The inside walls of the submarine are
concreted much like its exterior.
The rest of the work at the Warren Lasch Conservation Center has
focused on the upcoming excavation of the crew compartment. Scientists worked out bugs in
their data systems computer, prepared to take a course on interpreting the load cell
readings and had the tank swept out by a pool company.
The load cells can tell scientists if there is any change in
stress to the hull and can warn them ahead of time if a strap, which holds the sub in
place, is weakening.
They swept the tank to make sure there's no doubt that anything
in it is from the sub. During tours, someone could have accidentally - or as a joke -
dropped something in. Neyland said they don't want to be guessing about the origin of
anything they find.
Archaeologists are finding evidence of bilge water residue as
they excavate the rear section of the sub.
About 10 buckets of mud have so far been pulled from a three-foot
long hole in the vessel's rear right side during the first phase of excavation at the
Warren Lasch Conservation Lab.
In the mud, scientists are discovering the presence of oil,
organic material and other residue typically associated with a vessel's bilge. It has a
Also, there are small pieces of iron being found. When put
together, the pieces may represent the section of hull that was ripped open when the
mysterious hole was formed, possibly by a dragged anchor.