ODU FACULTY AID MONITOR CONSERVATION
A 17th-Century Swedish battleship salvaged from the bottom of Stockholm's harbor more than 40 years ago, now one of the premier maritime exhibits in the world, could hold lessons for scientists trying to conserve portions of the 19th century ironclad battleship the USS Monitor.
"It was the Swedish ship, the Vasa, that got us to thinking about potential problems with the Monitor," said David Burdige, professor of ocean, earth and atmospheric sciences at Old Dominion University. He is assisting another ODU faculty member, Desmond Cook, professor of physics, in offering scientific consultation to the Monitor conservation project at the Mariners' Museum in Newport News.
During the unusually wet summer of 2000 in Stockholm, the Vasa Museum experienced several spikes in relative humidity, and the battleship developed a "rash." Beams and wooden artifacts produced extremely acidic precipitates of white and yellow salts. "This was happening decades after the ship was taken from the water," Burdige explained. "And it was something that brought the integrity of the wood into question."
The culprit turned out to be sulfur, which is commonly found in the mud at the bottom of the sea. A wreck that rests for a long period in the mud can become impregnated with sulfur.
The Monitor was discovered in 1973 in mud 240 feet below the surface of the Atlantic Ocean off Cape Hatteras, N.C. It had sunk in a storm in December 1862, just a few months after its historic, indecisive battle with the ironclad CSS Virginia (formerly the Merrimack) in Hampton Roads. The Confederates had run the Virginia aground and destroyed it so it would not fall into the possession of the enemy.
What schoolchildren come to know as the Civil War Battle of the Monitor and Merrimack signaled a shift in battleship construction from wood and sail to iron and steam. The battle's significance will be commemorated by the USS Monitor Center at The Mariners' Museum, which is scheduled to open in 2007, coinciding with the celebration of nearby Jamestown's 400th anniversary.
The largest portions of the Monitor that have been raised and taken to The Mariners' Museum are the famous iron turret, iron propeller and steam engine, but there are also numerous pieces of wood among hundreds of artifacts that conservators have set to preserving.
"Some pieces that were recovered two decades ago, and then stored after initial treatment by conservators, showed signs of sulfur impregnation when they were examined recently," Burdige said.
Burdige enlisted his friend, David Velinsky, a biogeochemist at the Academy of Natural Sciences in Philadelphia, to test samples of the wood.
"What we're doing is measuring for sulfur and carbon to help determine how much of it is in the ship so that conservators can figure out the mechanism for minimizing the impact of the sulfur," said Velinsky, who received his doctorate degree in oceanography from ODU in 1987.
Explained Burdige: "The work we are doing is to better understand the processes that affect marine artifacts in the water and, more importantly, once they are brought up. The latter is particularly important in terms of their long-term preservation." The work may help conserve not only the wood recovered from the Monitor wreck, but also the metals, Burdige said.