They want to display this crate of Enfield rifles out of the water. But safeguarding the wood involves a lot of research, care.

The CSS Stono rifles (Photos by Don Scarbrough, interpretive range at SCSP)

Historic preservation specialists in Georgia are researching various ways to treat a wooden crate and 20 Enfield rifles that have been kept in an aquarium, where filtered freshwater continues to draw out salt and other contaminants.

The crate carried by the blockade runner CSS Stono has been on display for seven years at Sweetwater Creek State Park in Douglas County, west of Atlanta. The British-made Enfield was the second-most widely used infantry weapon in the Civil War after the Springfield.

The aim is to eventually display the weapons out of water, said Josh Headlee, curator and historic preservation specialist with the Georgia Department of Natural Resources.

The crate when it appeared briefly uncovered by water in January

“Essentially, we are testing or working with some products that we’ve never used before. So before we try them on something as important as the rifle crate we test it on an inconspicuous piece of waterlogged wood to see how well it does,” he wrote in a recent email.

“This is something that most museum professionals or conservators are familiar with – before you use a product on an important artifact you test it on a “non-important” item or in a well-hidden spot on the artifact before you use it on the entire item.”

The products are designed to displace water in the wood with preservatives that help to solidify the wood so it can be permanently exposed to the air. “We just want to make sure that what we do isn’t going to harm the rifles in any way," said Headlee.

The visitor center is currently closed due to the coronavirus pandemic

The CSS Stono, laden with precious arms, munitions and goods from Europe, in 1863 ran aground on a submerged sandbar off Fort Moultrie in Charleston (S.C.) Harbor while trying to evade Federal ships. The rifles remained in the water for more than a century.

An archaeological diver pulled up the crate from the South Carolina shipwreck in the late 1980s. Officials did not initially know how many of the highly-prized Pattern 53 rifles were inside, their position or condition. Each weapon originally weighed about 9 pounds and was approximately 53 inches long. The bore is .577-caliber.

Every six months or so, technicians travel to Sweetwater Creek to examine the cache and clean the tank. Last year, Headlee said the remains of the walnut rifle stocks were in good shape, while the crate itself and a metal lining that protected the rifles have not fared so well. The crate is likely made of pine, a softer wood. And the metal lining, made of an alloy, appears to be waterlogged. The iron rifle barrels, locks and bayonets deteriorated because of years of saltwater corrosion.

In January, technicians drained the 3,000-gallon tank and again cleaned the crate and installed a new filter.

A closeup view of the rifle stock remnants (Don Scarbrough)

“We were having a little bit of algae/fungus problem … and it was clouding the water and ruining our filters and pumps,” said Headlee. “This new pump has a UV light unit in it that the water travels through that is supposed to help control the algae growth.  We’ve also added a mild fungicide to the water to help keep everything clear.”

“It pretty much cleared up right away,” Sweetwater interpretive ranger Don Scarbrough said of the tank’s appearance following the work in January.

Because of the coronavirus pandemic, the Sweetwater visitor center housing the aquarium has been closed since mid-March.

The park staff recently resumed tours of the ruins of the New Manchester textile mill, which operated during the Civil War, Scarbrough said.