Meantime the Thirteenth Army Corps had been moved down to Grand Gulf, ready to storm the Rebel work as soon as Porter's gunboats had silenced the batteries. A vigorous fire was kept up for more than five hours, but the enemy's batteries proved too strong, and a change of plan was necessary. Grant accordingly took his troops back some distance, disembarked and marched across to the plain just below Grand Gulf. That night the transports and barges were conveyed past the batteries in safety, the gunboats following, and early on the morning of April 30th the troops were taken across the river. Some days of skirmishing and manoeuvring followed, and on the third of May it was found that the enemy had fled from Grand Gulf, toward either Vicksburg or Jackson. Grant accordingly halted his army to wait for Sherman's arrival, and personally went back to Grand Gulf.
Sherman reached Young's Point on May 1st, and the next morning sent his Second Division up to Milliken's Bend. Sherman himself with the other two divisions marched on to join Grant. The junction was effected on May 8th. The day before Grant had ordered a general advance, which was now begun. McPherson at the right, was to move by the way of Rocky Springs and Raymond, to Jackson; McClernand at the left, was to go through Willow Springs, keeping as near the Black River as possible; while Sherman was to move on Edward's Station, striking the railroad between that point and Bolton. On May 10th Sherman destroyed the bridge over the Big Black River, and on the 11th he reached Auburn. The next day he dispersed a small force of the enemy at the crossing of Fourteen Mile Creek, and that evening met Grant just beyond the creek and went into camp. Word now came from McPherson that he had defeated two Rebel brigades at Raymond, and that the enemy had retreated to Jackson, where reinforcements were arriving, and where Joseph E. Johnston was to command.
Grant now determined to make sure of Jackson, and to leave no enemy behind him. So he directed Sherman and McClernand to march at once to Raymond. On May 14th Sherman and McPherson met the enemy near Jackson, and a lively engagement ensued. Before night the Rebels were defeated, and were in full flight, and that evening Grant, Sherman and McPherson met near the State House. The next day Sherman set one division of his army to work destroying the railroad, the arsenal, the government foundry, and various other military works. A valuable cotton factory was also destroyed because the machinery it contained, if regained by the Rebels, could be easily converted into hostile uses. The penitentiary was burned by convicts, who had been released by the Rebels, and some other buildings were accidentally destroyed.