Divers on Monday deployed 3-D mapping sonar at the wreck site of a Federal gunboat forced to surrender during a brief broadside battle with the famous Confederate commerce raider CSS Alabama.
The USS Hatteras, largely buried in sand 20 miles south of Galveston, Texas, was the only Union warship sunk in combat in the Gulf of Mexico.
The side-wheeler went down Jan. 11, 1863, after the disguised Alabama lured it into battle (Hatteras at right in illustration).
A memorial service was held Monday at the site in memory of the two U.S. sailors who died during the battle, said Shelley du Puy, education and outreach coordinator for the Flower Garden Banks National Marine Sanctuary in Galveston. "Their bodies were never found. They are presumed to be still in the vessel," she said.
The aim Monday and Tuesday is to document the storm-exposed remains, about 60 feet beneath the surface. A paddlewheel and the stern are partially exposed.
Du Puy said she had not yet learned the condition of the wreckage, but federal agencies previously said it was believed to be largely intact. The hull is believed to be entirely covered by sand.
"It is mapping little sections of the wreck one at a time," Du Puy told the Picket about the work of sonar. "It will be pretty high resolution. They will stitch these pieces together as one 3D mosaic (image)."
"We want to help further the knowledge base and use this in our education and outreach."
The National Oceanic and Atmospheric Administration (NOAA) is working with the Bureau of Ocean Energy Management (BOEM) and the state of Texas on the mapping project.
According to Du Puy, 2008's Hurricane Ike and other conditions made this week an ideal time to map the wreck.
"Typically, the visibility is not good," given heavy silt and currents, said Du Puy. "There is a lot of wave action going on."
Because it is a U.S. Navy ship and two men died, the 210-foot USS Hatteras -- listed on the National Register of Historic Places -- has special protection.
Recreational divers are allowed, but they are not permitted to disturb or damage the wreck or take any artifacts, said Robert Neyland, head of the underwater archaeology branch at the Naval History and Heritage Command in Washington.
The Hatteras was part of the West Gulf Blockading Squadron commanded by Union Rear Adm. David Farragut. The squadron blocked the passage of goods, supplies, and arms to and from the Confederacy on the Atlantic and Gulf coasts.
Built in 1861 as the St. Mary, the iron-hulled Hatteras was converted into a gunboat. After successful service in Florida, the boat joined Farragut's squadron and captured seven Rebel blockade runners off Louisiana.
According to Edward T. Cotham, Jr. of the Terry Foundation, Union vessels were sent to avenge the loss of Galveston to Confederate forces.
On Jan, 11, 1863, the Hatteras was ordered to pursue a vessel that showed on the horizon.
"She chased the intruder for four hours, closer and closer into shore, and farther and farther from her supporting fleet," according to an article on the BOEM website. "Finally, as dusk was falling, the Hatteras came within hailing distance of the square-rigged, black-hulled vessel."
Skipper Homer C. Blake demanded to know the identity of the ship commanded by Raphael Semmes (photo above; as a side note, Semmes mistakenly thought Union forces had retaken the city and had arrived to harass transports supporting an invasion).
"Her Britannic Majesty’s Ship Vixen," came the reply. Blake ordered one of Hatteras’ boats launched to inspect the "Britisher."
At some point, the Confederate crew identified the ship as the Alabama.
The battle was a mismatch. The Alabama was a superior vessel and was well-manned, according to Neyland.
Eights minutes into the broadside exchange, a Confederate shell set a fire near the Hatteras' magazine. Meanwhile, many of its armor plates had been blown off and water poured in.
With his vessel immobile and about to be the subject of deadly raking fire, Blake surrendered, according to Cotham. Two men died and the remaining 121 surrendered.
The battle was over in 13 minutes; the USS Hatteras soon sank.
Asked whether the USS Hatteras had a chance, Neyland told the Picket, "There is always a chance of a lucky shot."
NOAA said it plans to present results from the mapping mission in Galveston next January during local events marking the 150th anniversary of the sinking of the Hatteras.
After Galveston, the CSS Alabama went on to greater fame when it battled the USS Kearsarge, which sank the Confederate raider off Cherbourg, France, in June 1864.
The Alabama also is the property of the United States, said Neyland. Many of its artifacts, including three guns and personal effects, were removed. Items are stored or displayed in locations in the United States, including Mobile, Ala.
Illustration and photos credit: U.S. Naval Historical Center
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