<P> On June 21, elements of the II Corps probed toward the railroad and skirmished with Confederate cavalry . By the morning of June 22, a gap opened up between the two corps . While the II Corps moved forward, the VI Corps encountered Confederate troops from Maj. Gen. Cadmus Wilcox's division of Lt. Gen. A.P. Hill's corps and they began to entrench rather than advance . Brig. Gen. William Mahone observed that the gap between the two Union corps was widening, creating a prime target . Mahone had been a railroad engineer before the war and had personally surveyed this area south of Petersburg, so he was familiar with a ravine that could be used to hide the approach of a Confederate attack column . At 3 p.m., Mahone's men emerged in the rear of the II Corps division of Brig. Gen. Francis C. Barlow, catching them by surprise, and Barlow's division quickly collapsed . The division of Brig. Gen. John Gibbon, which had erected earthworks, was also surprised by an attack from the rear and many of the regiments ran for safety . The II Corps troops rallied around earthworks that they had constructed on the night of June 21 and stabilized their lines . Darkness ended the fighting . </P> <P> On June 23, the II Corps advanced to retake its lost ground, but the Confederates had pulled back, abandoning the earthworks they had captured . Under orders from General Meade, the VI Corps sent out a heavy skirmish line after 10 a.m. in a second attempt to reach the Weldon Railroad . Men from Brig. Gen. Lewis A. Grant's 1st Vermont Brigade had begun tearing up track when they were attacked by a larger force of Confederate infantry . Numerous Vermonters were taken prisoner and only about half a mile of track had been destroyed when they were chased away . Meade was unable to urge Wright forward and called off the operation . Union casualties were 2,962, Confederate 572 . The battle was inconclusive, with advantages gained on both sides . The Confederates were able to retain control of the Weldon Railroad . The Federals were able to destroy a short segment of the Weldon before being driven off, but more importantly, the siege lines were stretched further to the west . </P> <P> In parallel to Birney's and Wright's infantry action at the Jerusalem Plank Road, Brig. Gen. James H. Wilson was ordered by Meade to conduct a raid destroying as much track as possible south and southwest of Petersburg . Grant considered Wilson's 3rd Division of the Cavalry Corps too small to conduct the operation alone--particularly since Meade required Wilson to leave 1,400 men behind for picket duty--so he directed Butler to contribute Brig. Gen. August Kautz's small division (2,000 troopers) to the effort . Early on the morning of June 22, 3,300 men, and 12 guns organized into two batteries, departed Mount Sinai Church and began to destroy railroad track and cars of the Weldon Railroad at Reams Station, 7 miles (11 km) south of Petersburg . Kautz's men moved to the west to Ford's Station and began destroying track, locomotives, and cars on the South Side Railroad . </P> <P> On June 23, Wilson proceeded to the junction of the Richmond and Danville Railroad at Burkeville, where he encountered elements of Rooney Lee's cavalry between Nottoway Court House and Black's and White's (modern - day Blackstone). The Confederates struck the rear of his column, forcing Col. George A. Chapman's brigade to fend them off . Wilson followed Kautz along the South Side Railroad, destroying about 30 miles (50 km) of track as they went . On June 24, while Kautz remained skirmishing around Burkeville, Wilson crossed over to Meherrin Station on the Richmond and Danville and began destroying track . </P>

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