Statistics for occurrence #1 of “Roanoke River” in chapter 41 of Admiral David D. Porter, The Naval History of the Civil War.:

...was ever on the alert to surprise the enemy, and his escaping death for so long a period is remarkable. The Confederates had been employed in building a powerful ram, called the Albemarle, on the Roanoke River , and, knowing that the Federals had no vessel that could compete with her, it was arranged to fit out an expedition of Confederate soldiers, which, in conjunction with the ram, should make a descent ...
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