Scale 1:30,000. LC Civil War Maps (2nd ed.), 117.1 Harbor chart annotated in red to show the sector of fire for guns situated at Oyster Point and Fort Hale, Connecticut. Information added to chart probably reflects the situation during the Civil War. "Transferred from Office Chf. Engr. [Defenses] of Washington, to Engr. Dept. Jan'y [1866]." Description derived from published bibliography. Available also through the Library of Congress web site as raster image.
United States Coast Survey
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