Sunday, July 23, 2017

A trip to the CSS Georgia recovery site: Nine really cool things and a couple bummers for researchers, conservators

Clamshell prepares to lift mud (and possible artifacts) to deck
Spikes used to join armor components (Picket photos)

I couldn’t let a narrow window of opportunity close, so I drove most of the night to Savannah, Ga., to spend a few hours Saturday aboard barges recovering the last significant portions of the Confederate ironclad CSS Georgia. That on-site project will be completed in the coming days. Thanks to the Savannah office of the U.S. Army Corps of Engineers for having me on board. All photos by the Picket unless noted otherwise.

Protected by railroad iron

I finally got face-to-iron with two large casemate sections that were lifted from the Savannah River this summer (by the way, they are being placed in a different spot back river this weekend for safekeeping).

I still am trying to get my head around this innovative way of building armor when you don’t have more raw resources and manufacturing capabilities.

Sprinklers are used to keep casemate safe from corrosion

Jim Jobling, with the Conservation Research Laboratory at Texas A&M University -- which is conserving much of the CSS Georgia’s 16,200 artifacts -- said each rusted rail is 4 inches by 4 inches, 24 feet long and weighs about 400 pounds. The iron is backed by 8 inches of pine and another 12 inches of heavy lumber.

Archaeologist Gordon Watts, who has dived and studied the wreck site for decades, said there were at least seven patterns of interlocking railroad iron used to make the casemate in 1862.

Where did the ship builders get the railroad iron?

Two rail pieces, lower right, with tar used to stop leaks (USACE)

“They were likely to be confiscated,” Watts said – specifically from Northern-owned companies, including a line from Brunswick, Ga., to Jacksonville, Fla. The nephew of US Navy Secretary Gideon Welles came to Savannah after the war to try to recover iron and other material, he said.

The CSS Georgia was prone to leaking, from above and below, and crew members used tar, plaster and other materials to fill gaps in the armor. Experts believe the engine was in service at all times, to power pumps that kept the leaky gunboat from sinking.

“It was obviously a pretty miserable place,” said Watts.

Detailed drawings bring artifacts to life

Gordon Watts measures portion of casemate armor ...
... and documents the different patterns of railroad iron used for armor

Gordon Watts, a contract archaeologist from North Carolina, has produced numerous detailed sketches of CSS Georgia components, something I first noticed during a visit to the 2015 recovery operation involving U.S. Navy divers.

“If I draw it, than I have to think about it,” Watts said of each item. He said he can get more interpretation that way than from just observing mosaic images.

He points to components of engine (Picket photos)

Find of the summer: Engine cylinders

They are not exactly sexy, but two steam cylinders brought up by a grappling hook will tell a lot about the ironclad’s propulsion. It’s known the CSS Georgia was underpowered and thus became a floating battery near Fort Jackson to repel any Federal naval advance on the city.

Jim Jobling washes off engine cylinders, frame mount (USACE photos)

Officials don’t know where the engines made; it’s possible they were taken from another vessel. The cylinders were part of the piston system that drove shafts for two propellers (only was of the props has been found and brought up).

Watts said he is aware of two or three other Confederate vessels, including the Arkansas, that featured railroad iron armor.

Now there’s enough of the machinery – with boiler and shaft parts – to get a better sense of the power and speed capabilities of the ironclad. Jobling said propeller and engine data, along with photos, are being sent to the U.S. Naval Academy for analysis.

“We can then figure out how strong the engine was, how efficient the propeller was and figure out the size and weight it carried,” he said. “How underpowered was she?”

Gun port and end piece

Note openings near rope that were part of a gun port
Casemate end piece had angle at top (Picket photos)

Three fascinating sections of casemate headed for conservation in Texas rested on the end of one barge. Sprinkler water kept them protected from corrosion until they can be placed in tanks.

One was a portion of a gun port. Five guns, including 9-inch Dahlgrens and a 6-pounder, were recovered in 2015, but others were brought up earlier. The CSS Georgia could carry 10, but it probably carried fewer when it was scuttled in December 1864.

The end piece could be used in a museum exhibit that explores the design of the vessel. There are no surviving plans, and archaeologists are not even sure of the ironclad’s size or weight. Watts said evidence points to it being 45-50 wide at the beam and between 180 and 200 feet long. Officials said with five guns in service, a crew of between 100 and 125 was likely serving the CSS Georgia.

Buckets of artifacts

Wood roller with brass fitting. Its use? Not yet known
Piece of artillery grapeshot (Picket photos)

During this past month’s mechanized recovery, archaeologists have placed smaller finds in water-filled white buckets lining the side of one barge.

Crews this year, unlike in 2015 and earlier, have found very few personal items beyond uniform buttons and a couple bullets, but it was interesting to see what was in the buckets: Various CSS Georgia artifacts, including parts of a pulley/rigging, and pre-Columbian pottery that washed into the salvage site.

Clamshell, shovels and hard labor

A dozen or so archaeologists worked the hot deck of a barge on Saturday, using large fire hoses and shovels to go through hundreds of pounds of mud placed in separate bays by a crane.

Each bay featured a screen on one end that would trap possible artifacts as the high-volume water cut through the muck. On this half day, 13 dips of the clamshell were made (repairs on the crane reduced the haul); there were as many as 80 scoops performed on longer days.

Screen on right traps artifacts during washing
Zones used by grapple and clamshell device (Picket photos)

Will Wilson of Panamerican Consultants utilized USBL, a method of underwater acoustic positioning, to direct the crane where to drop a large clamshell device to pick up the scoops from grid squares.

The recovery operation also has used a large grapple to pick up bigger items from the river bottom 40-45 feet down.

Replicas made from 3D plastic

Jim Jobling with replica of propeller recovered in 2015 and since conserved

Jobling, Watts and Stephen James, lead archaeologist on-site for Panamerican Consultants, will speak at a Corps public event in Savannah on Aug. 2.

The program includes portions of a documentary, "Dredging up the Past: Recovery of the CSS Georgia Shipwreck."

Columbiad gun sight, but not the gun, was pulled up.
Replica of pre-Civil War artillery sword hilt (Picket photos)

Jim Jobling of the Texas A&M conservation lab has procured small educational replicas of some of the artifacts found in recent years. “I scanned the artifacts using an accurate laser scanner” and they were sent to a printer to have them rendered in plastic.

Dealing with recovered ammo

The last part of this year’s final CSS Georgia recovery will be the deactivation of artillery shells found in the muck. Thus far, a Brooke shell with an Archer fuse and a 9-inch Dahlgren round rest in baskets below the surface awaiting this operation. But more rounds could be found in coming days.

The CSS Georgia may have had 500 shells for the five recovered guns. But how many went down with the ship and are still in the Savannah River? Jobling said 99 were brought up and saved in the 1980s, 240 in 2015, and two thus far this year. All precautions are being taken.

… And a couple not so cool things

The Georgia’s hull is gone, eroded by time, dredging and destructive teredo worms.

That makes it extremely difficult to configure components. “If we had a hull, we could tell how things were arranged,” said Watts.

While finds in 2015 and this year have added to the CSS Georgia’s story, Watts said, the absence of the hull and other information may leave many mysteries unanswered.

(Picket photos)

Jobling, on a tour of the casemate sections, pointed to the myriad holes (above) left by teredo worms. Crews were asked to gain wood samples from the casemate for dendrochronology – to learn the age and condition of the trees cut for the job in 1862. But given the damage, they had to get samples from other CSS Georgia lumber.

“There was a lot of old-growth wood in Georgia in that time period,” said Jobling. “They were probably cut in early 1862 … she was built with green wood. They had to cork her and fill the cracks between the timbers.”

Sections of rusting railroad iron (Picket photo)

The ‘Mud Tub’ a winner after all?

A 2015 article by the Army Corps of Engineers details frustration among the ironclad’s crew, relegated to the back lines and on a vessel that was stationary, and residents of Savannah who raised money to build a ship that didn’t have much engine power. The lure of desertion and drinking were common on the CSS Georgia.

One woman wrote: “Our iron floating battery is a splendid failure. She has been taken down between the forts and they are obliged to keep her engines at work the whole time to prevent her sinking, she leaks so badly. The officers had a consultation, a day or two after she went down, to decide on the propriety of throwing over her coal to keep her afloat. During the long storm last week, she leaked also from the roof, so that there was not a dry spot for the men or anything else in the vessel, even their beds were wet.”

Gordon Watts takes break from examination of casemate

But Watts has a more forgiving view. The CSS Georgia was a valuable part of the city’s defenses for two years, in concert with Fort Jackson, torpedo mines, pilings and other vessels.

“When you get down to it, it was really effective,” he said.

Casemate section stays cool in summer heat. (Picket photo)

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