Overall command for defense of the District was given to Major General Christopher C. Augur as commander of the XXII Corps. Major Generals Quincy Gillmore and Alexander McCook commanded the Northeast sector and the reserve post at Blagden Farm, respectively. Augur commanded 31,000 troops and 1,000 artillery pieces in 160 fortifications, batteries, and trenches. Eighty-seven fortifications were north of the Potomac (facing Early's approach) with 484 heavy guns and 13,986 men. Land was cleared surrounding the city to create open fields of fire. Six companies of the 8th Illinois Cavalry were stationed in front of the northern defenses.