...Parker's Store, and if practicable, to the crossing of the road from Robertson's Tavern. A division of cavalry, under Brigadier-General Gregg, was ordered to cross at Ely's Ford, and proceed on the Catharpin road as far as Corbin's bridge, to cover the left flank of the army. A division of cavalry, under General Custer, held the upper fords of the Rapidan; and the Third division, under General Merritt,...