So long as the stout-hearted general continued his march south all his supplies had to be brought over the Mississippi Central Railroad from Holly Springs, near the Tennessee border. A troop of 3,500 Confederate cavalry, making a long detour around his army, swooped down upon Holly Springs, December 20th, captured the garrison of 1,300 men, and destroyed all the stores, valued at $2,000,000. For two weeks the Union army had to live from the enemy's country, and then after all to fall back to Holly Springs. Meanwhile Sherman, ignorant of his superior's ill fortune, descended the Mississippi, and with a force of 30,000 made during the last days of the year an unsuccessful attack upon Vicksburg. Very early in January, 1863, McClernand arrived near Vicksburg with re-enforcements. The last of the month, Grant, who had given up the land expedition, took command in person. Sherman's repulse had shown that Vicksburg could not be taken from the water side. A position must be gained in the rear. This seemed, and indeed proved, an almost impossible task. The Mississippi was unusually high, and the surrounding country a vast network of bayous and swamps. The winter passed away in fruitless labors to make some sort of a water passage to the rear of Vicksburg, either above, via the Yazoo, or around through Louisiana to some point below the city, whence the army could cross again to the Vicksburg side of the Mississippi and strike Pemberton's stronghold from the southeast. In most of these attempts Grant himself had little faith, but the army was better at work than idle. At last he resolved, without attempting a regular canal, partly by land but utilizing bayous and creeks as he could, to swing his army across west of the river to New Carthage, south of Vicksburg, run the Vicksburg batteries with the fleet, and, uniting his land and water forces in the capture of Grand Gulf, to gain the rear of Vicksburg by way of the Big Black River. It was a bold plan, but it succeeded. In April, by building corduroy roads through miles of swamp and bridging numberless bayous, the general succeeded in reaching New Carthage, some twenty miles south of Vicksburg, with a good part of his land forces. On the night of April 16th, the gunboats and provision transports ran the gauntlet of Vicksburg's guns with little damage. The last of the month a landing was effected just below Grand Gulf, on the east bank, fifteen or twenty miles still farther south of Vicksburg. The enemy made some resistance, but were driven back.