In the late morning of September 20, 1863, General Joseph Wheeler's cavalry rode north along the east side of West Chickamauga Creek to the area opposite Lee and Gordon's Mills, arrived there about 3:00 p.m., dismounted, forded the creek north of the mill, formed a line of battle, and advanced through the woods, driving Federal forces before them and pursuing them beyond Crawfish Spring, the field hospital of McCook and Crittenden's corps. A cavalryman of the 4th Tennessee Cavalry recalled that the attack revealed why fighting had broken out so far from the infantry line: Federals had been driven from the line of the Chickamauga, and Crawfish Spring was the only accessible water for them on that wing of the army, where their killed and wounded were brought. When the Confederates came in sight of Crawfish Spring, the crowded scene of men, tents, vehicles, dead, wounded, and hospital attendants at first made them think they had captured the whole Federal army. Wheeler reported that he had been ordered to move his available men to Lee and Gordon's Mills and attack, that after crossing the river they vigorously assailed the enemy and quickly sent him retreating in confusion, and that the pursuit captured about 1,000 prisoners, 20 wagons, a large amount of arms and ordnance stores, and, near dark, five large hospitals with medicines, camp equipage, and many wounded prisoners. The pursuit continued until two hours after nightfall, when the cavalry retired to feed their horses, and as they passed back to recross the Chickamauga, the road was full of ambulances and litters carrying the killed and wounded, leaving participants with a stark view of the battlefield's human cost.