...th of the railroad, drive in the enemy's pickets at night, and at daylight next morning engage him heavily with skirmishers, occupying him during the entire day; and that on that night I move by the Warrenton road by Hankinson's Ferry; to which point you should previously send a brigade of cavalry, with two field-batteries, to build a bridge there and hold that ferry; also Hall's and Baldwin's, to cover m...