...he Chambersburg and Fairfield routes, the army to march after night by the latter,--the Second Corps as rear-guard, the First to follow the Third and push on to secure the crossings of the Potomac at Williamsport and Falling Waters. It was daylight of the 5th when the road was open for the march of the First, and a later hour of the morning before the Second could follow. Pursuit was made by the enemy...