Map of the Dismap Swamp Canal, 1867
Map is titled "Dismal Swamp Canal connecting the Chesapeake Bay with Currituck, Albemarle and Pamlico Sounds and their tributary streams, by D. S. Walton, Civil Engineer, 1867." The "Proposed Southern Air Line" from Edenton to South Mill was a railroad line that would have gone in a straight line across at least one river -- in a "bee line" or, as was said at the time, an "air line." See this explanation from Wikipedia.
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