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Two thousand, seven hundred and fifty years ago, two ships loaded with a cargo of wine set sail from ancient Phoenicia (present-day Lebanon) headed for a foreign port. But instead of gracing the table at a royal feast, the cargo ended up at the bottom of the Mediterranean Sea when the ships sank, probably in a storm. For nearly three millennia, the ships rested undisturbed in more than 1,000 feet of water. In June, the ships&emdash;the oldest deep-sea shipwrecks to be discovered to date&emdash;were located and explored by a crew of scientists and engineers under the leadership of famed oceanographer Robert Ballard, discoverer of the Titanic. Using the latest in high technology, including a deep-water side-scan sonar system and a remotely operated vehicle, the wrecks were closely explored and photographed. The larger of the two ships, at 58 feet, is the largest pre-classical-era shipwreck ever discovered. The smaller ship measures 48 feet. One of the crew members on Ballard's research vessel was Dennis Piechota, conservator of Big Dig artifacts for the University's Center for Cultural and Environmental History. When the Phoenician artifacts emerged from the sea, it was Piechota's job to prevent their deterioration. The twelve amphorae, (elongated clay vessels that held about twenty quarts each), other crockery, a wine decanter, and an incense burner were fragile, having been under extreme pressure for thousands of years, and would otherwise have begun deteriorating almost immediately. Piechota has two objectives: keep the artifacts wet while removing the sea salt, and then to dry them slowly to avoid cracking. The amphorae and other pottery are made of resin-coated, low-fired clay. Some of the artifacts&emdash; about ten percent&emdash; are prone to cracking, says Piechota. "The theory is that at those water depths, the clay converts back to an unfired state. This problem is controlled by drying the artifacts at a high humidity for several weeks. That way, the skin of the pottery is as moist as the core," he says. The artifacts will eventually be put on exhibit so that they can be viewed by the public. The artifacts from the Phoenician ships are the latest that Piechota has worked on during his ten-year association with Ballard. Ballard has now turned his attention to the Black Sea, which is believed to be the resting place of many well preserved ancient ship wrecks. Chances are good, says Piechota, that the Black Sea will be a future destination for exploration and discovery. Since July, Piechota has been back in his laboratory at the Center for Cultural and Environmental History, where he is surveying the Big Dig artifacts which were placed in the care of UMass Boston in February of 1997. Anthropology Prof. Steven Mrozowski, who was instrumental in bringing the Big Dig collection here and directs the Center, hired Piechota for the massive task of creating a ten-year conservation plan for the 200,000 Colonial and Native American objects in the collection. Piechota also works part time with Harvard University's Semitic Museum on conserving a collection of cuneiform tablets from the Akkadian civilization, circa 3000 B.C. Piechota expects to continue working with Ballard in the future. Estimates are that there are vast numbers of shipwrecks at the bottom of the seas. "For every shallow water shipwreck found, records fromLloyd's of London suggest that there may be 10,000 deep-sea wrecks out there, waiting to be discovered," says Piechota. |
