I shall inclose your Excellency a plan of the enemy's works, and of their strength, from the best ac counts we are able to get. They have never been out of their lines since the siege began, till, night be fore last, Colonel Bruce came out with one hundred and fifty men, to take off a small picket of ours, posted at the neck of Easton's beach. He partly succeeded in the attempt, by the carelessness of the old guard. He came over after dark, and lay in ambush, that when the new guard went down to take their post, the enemy came upon their backs before they discovered them, it being very dark. We lost twenty-four privates and two subalterns. Ten of the picket got off.
Letter to George Washington (August 1778)