High Technology Locates Ships
Underwater archaeology is often more difficult than terrestrial archaeology, especially when visibility is poor because of salty water. Side scan sonars and magnetometers (sophisticated metal detectors) are employed in the search for underwater archaeological remains. Promising targets are then investigated by probing and, if warranted, excavated using water induction dredges that suck up the silt covering the site and deposit it through a screen on a ship or other surface, where it can be sifted for artifacts. Artifacts recovered from underwater sites need special treatment to preserve them.
Background: Sketch of Barge by Commodore Joshua Barney.
(Inscription under the image in the lower left) Copper sheathing was often used on ships to protect the outer hull below the water line from worm-like creatures called wood borers. Inside the hull, it was used to form watertight compartments where food and other perishables could be protected from water damage. This sheathing was fastened to the gunboat with small copper nails, like those above.
(Inscription under the image in the upper center) Above top: Jenna Watts and Marc Henings measure artifacts.
(Inscription under the image in the lower center) Grapeshot consisted of cast iron balls about the size of golf balls, which were arranged around an open frame and packed in a bag. When fired from a cannon, the individual balls spread out in a shotgun-like manner. Grapeshot was designed to kill people, and was used against troop concentrations with devastating results. Grapeshot illustration courtesy Roundshot and Rammers, by Harold L. Peterson.
(Inscription under the image on the right) In the field, East Carolina University graduate students (L to R) Kim Eslinger, Matt Muldorf, and Tane Casserley record and measure a bow apron timber from an American War of 1812 gunboat.
The Archaeological research was supported in part by grants from the Department of Defense's Legacy Resource Management Program. The National Park Service's American Battlefield Protection Program, and the Maryland Maritime Archeology Program.
St Leonard CreekGunboats No. 137 & 138During 1998 and 1999, two of United States Chesapeake Flotilla's gunboats, No. 137 and No. 138, were located and partially excavated near the headwaters of St. Leonard Creek. Among the artifacts found were a gun fling, .69 and .75 caliber musket shot, several buttons, grapeshot, and copper sheathing nails.
All the artifacts were treated at the Maryland Archaeological Conservations Laboratory at Jefferson Patterson Park and Museum.
Commodore Joshua Barney considered these two boats to be slow and difficult to sail, so they were scuttled in shallow water before the Flotilla escaped up river.
The British later finished their destruction by setting the vessels on fire. The two boats found by underwater archaeologists exhibited tell-tale burn marks from the British action. This damage, along with the artifacts, the vessels' size, and their place of discovery, all confirm that they are the American gunboats.
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