cohesion and morale. Because he was operating on the offensive in enemy territory, Grant had to defend his bases of supply and the lines extending from them to his army in the field; it was principally for this reason that Grant chose to maneuver repeatedly around Lee's right flank during the campaign, relying on waterborne supply lines instead of the railroads, such as the Orange and Alexandria, in Virginia's interior. Furthermore, since many of his soldiers' three-year enlistments were about to expire, they were naturally reluctant to participate in dangerous assaults. To deal with these challenges, Grant supplemented his forces by reassigning soldiers manning the heavy artillery batteries around Washington, D.C., to infantry regiments. Battles The Wilderness (May 5–7, 1864) The Overland Campaign began as Grant's forces crossed the Rapidan River on May 4, 1864. Grant's objective was to force an engagement with Lee, outside of his Mine Run fortifications, by either drawing his forces out or turning them. Lee, displaying the audacity that characterized his generalship, moved out as Grant desired, but more quickly than Grant anticipated; Union forces had insufficient time to clear the area known as the Wilderness, a tangle of scrub brush and undergrowth in which part of the Battle of Chancellorsville had been fought the previous year. By forcing a fight here, Lee effectively neutralized the Union's advantage in artillery. He ordered Ewell's Corps to advance on the Orange Turnpike, A.P. Hill's in parallel on the Orange Plank Road, and James Longstreet's from the distant Gordonsville. Early on May 5, Warren's V Corps was advancing south toward the Plank Road when Ewell's Corps appeared in the west on the Turnpike. Meade halted his army and directed Warren to attack if the Confederates were a small, isolated group. Ewell's men erected earthworks on the western end of the clearing known as Saunders Field. Warren requested a delay from Meade so that Sedgwick's VI Corps could be brought in on his right and extend his line. By 1 p.m., Meade was frustrated by the delay and ordered Warren to attack before Sedgwick could arrive. The brigade of Brig. Gen. Romeyn B. Ayres had to take cover in a gully to avoid enfilading fire. The brigade of Brig. Gen. Joseph J. Bartlett made better progress to Ayres's left and overran the position of Brig. Gen. John M. Jones, who was killed. However, since Ayres's men were unable to