CHAPTER XX.

Advance of General McClellan toward Centreville; his Report.--Our Forces ordered to the Peninsula.--Situation at Yorktown.--Siege by General McCellan.--General Johnston assigned to Command; his Recommendation.--Attack on General Magruder at Yorktown.--Movements of McClellan.--The Virginia.--General Johnston retires.--Delay at Norfolk.--Before Williamsburg.--Remark of Hancock.--Retreat up the Peninsula.--Sub-terra Shells used.-Evacuation of Norfolk.--Its Occupation by the Enemy.