Selma fortifications at 2 p.m. He had placed Gen. Eli Long's division across the Summerfield Road with the Chicago Board of Trade Battery in support. He had Maj. Gen. Emory Upton's division placed across the Range Line Road with Battery I, 4th U.S. Artillery in support. Altogether, Wilson had 9,000 troops available for the assault. The Federal commander's plan was for Upton to send in a 300-man detachment after dark to cross the swamp on the Confederate right, enter the works, and begin a flanking movement toward the center moving along the line of fortifications. Then, a single gun from Upton's artillery would signal the attack by the entire Federal Corps. At 5 p.m., however, Gen. Long's ammunition train in the rear was attacked by advance elements of Forrest's scattered forces coming toward Selma. Both Long and Upton had positioned significant numbers of troops in their rear for just such an event. However, Long decided to commence his assault against the Selma fortifications to neutralize the enemy attack in his rear. Long's troops attacked in a single rank in three main lines, dismounted with Spencers carbines blazing, supported by their own artillery fire. The Confederates replied with heavy small arms and artillery fire of their own. The Southern artillery, in one of the many ironies of the Civil War, only had solid shot on hand, while just a short distance away was an arsenal which produced tons of canister, a highly effective anti-personnel ammunition. The Federals suffered many casualties (including General Long himself) but not enough to break up the attack. Once the Union Army reached the works, there was vicious hand-to-hand fighting. Many soldiers were struck down with clubbed muskets. But, in less than 30 minutes, Long's men had captured the works protecting the Summerfield Road. Meanwhile, General Upton, observing Long's success, ordered his division forward. The story was much the same for his men as on Long's front. Soon, U.S. flags could be seen waving over the works from Range Line Road to Summerfield Road. After the outer works fell, General Wilson himself led the 4th U.S. Cavalry Regiment in a mounted charge down the Range Line Road toward the unfinished inner line of works. The retreating Confederate forces, upon reaching the inner works, all rallied and poured a devastating fire into the charging column. This broke up the charge and sent General Wilson sprawling to the ground