▁Confeder ate ▁States ▁Ste amer ▁Alb em ar le , ▁under ▁the ▁command ▁of ▁Captain ▁James ▁W . ▁Co oke , ▁got ▁under way ▁down - river ▁toward ▁P ly mouth , ▁North ▁Carolina ; ▁its ▁mission ▁was ▁to ▁clear ▁the ▁river ▁of ▁all ▁Union ▁vessels ▁so ▁that ▁General ▁Robert ▁F . ▁H oke ' s ▁troops ▁could ▁storm ▁the ▁for ts ▁located ▁there . ▁She ▁anch ored ▁about ▁three ▁miles ▁( 5   km ) ▁above ▁the ▁town , ▁and ▁the ▁pilot , ▁John ▁Lock , ▁set ▁off ▁with ▁two ▁se amen ▁in ▁a ▁small ▁boat ▁to ▁take ▁sound ings . ▁The ▁river ▁was ▁high ▁and ▁they ▁discovered ▁ten ▁feet ▁of ▁water ▁over ▁the ▁ob stru ctions ▁that ▁the ▁Union ▁forces ▁had ▁placed ▁in ▁the ▁Thor ough fare ▁G ap . ▁Captain ▁Co oke ▁immediately ▁ordered ▁steam ▁and , ▁by ▁keeping ▁to ▁the ▁middle ▁of ▁the ▁channel , ▁they ▁passed ▁safely ▁over ▁the ▁ob stru ctions . ▁The ▁iron cl ad ' s ▁arm or ▁protected ▁them ▁from ▁the ▁Union ▁guns ▁of ▁the ▁for ts ▁at ▁Warren ' s ▁Ne ck ▁and ▁Bo yle ' s ▁Mill . ▁ ▁After ▁the ▁fall ▁of ▁P ly mouth , ▁the ▁U . ▁S . ▁Navy ▁raised ▁and ▁tempor arily ▁h ull - patch ed ▁the ▁Confeder ate ▁ram . ▁Near ▁the ▁end ▁of ▁the ▁war , ▁the ▁Union ▁gun bo at ▁ ▁to wed ▁Alb em ar le ▁to ▁the ▁Nor folk ▁Navy ▁Y ard , ▁where ▁she ▁arrived ▁on ▁ 2 7 ▁April