Parker saw distress signals from grounded British ships and raised the recall to give Nelson a lawful way to disengage if he could no longer continue. The signal offered discretion rather than an unavoidable order to retreat. Nelson acknowledged it but did not repeat it, making the famous remark about having a right to be blind sometimes. His subordinate Thomas Graves kept Nelson's close-action signal prominent while placing the recall where other ships could not readily see it. Captain Edward Riou, unable to see Nelson's flagship, obeyed Parker literally, withdrew his frigate force past heavier fortress fire, and was killed.
Notable Point · 1:00:20-1:03:09
Why Nelson ignored the recall signal
Parker's signal gave Nelson discretion to disengage; Nelson acknowledged it but continued the close action, producing the famous blind-eye episode.