In the meantime, Buell moved his troops rapidly forward until they developed the Confederate line of battle west of the Peach Orchard. The Southerners boldly charged the advancing Union infantry which had moved forward so rapidly that its artillery was still far to the rear. Without artillery support, the Federals were unable to withstand the violent assault of the Confederates and were forced to make a hasty retreat. The timely arrival and effective use of two batteries of artillery permitted the Union line again to advance, only to be driven back once more by the stubborn Confederates. The battle now raged the entire length of the field. Charge followed by countercharge moved the fitfully swaying line first toward the river and then toward the church. The advantage would seem to rest momentarily with the weary Southerners, but would soon be lost to their greatly strengthened opponent. Commands became so intermingled and confused that it was often impossible to distinguish between friend and foe. The Confederates, clad in a variety of colored uniforms, with no well-defined line and on an ever-changing front, suffered the heavier losses from the fire of their own troops. Meanwhile, General Beauregard, at Shiloh Church, anxiously awaited the return of couriers he had dispatched to Corinth to hurry forward Gen. Earl Van Dorn’s army of about 20,000 men, daily expected there from Van Buren, Ark. He had promised to make a junction with General Beauregard as soon as possible, but was delayed because he had no means of transporting his troops across the Mississippi. Unaware that Van Dorn was still in Arkansas, General Beauregard maintained his largest troop concentration in the vicinity of the church to defend the Corinth-Pittsburg Road so that reinforcements could be quickly moved onto the field. As soon as it became known that additional troops were not on the way, Beauregard realized that the road would have to be kept open as a possible line of retreat. The Union commanders were equally determined to drive the Confederates from the position. Consequently, furious fighting raged before the church long after the tempo of the battle had slackened on each flank. Despite all efforts of the Confederates, the Union line continued slowly to advance. In desperation the Confederates made a gallant charge, first expending their ammunition and then relying on the bayonet. The charge carried the surging line through waist-deep Water Oaks Pond, beyond which the fire from the adversary became so strong that the line was brought to an abrupt halt. Taking cover at the edge of a woods, they repulsed every attempt by the Federals to advance. [Illustration: _Arrival of Federal reinforcements._] [Illustration: _The first tent field hospital ever used for the treatment of the wounded on the battlefield was established at Shiloh, April 7, 1862._]