Colonel Grierson's cavalry force was now launched down from Tennessee to go tearing through the whole interior of Mississippi, and thoroughly frighten all its people, while he should break up, as he circuited far around Vicksburg, as many as possible of the railroads, bridges, and other means of communication, leading from the city back into the country, or from one part of the State to another. Grant's own troops moved down the river a total distance of seventy-five miles. The fleet and transports ran the batteries and ferried the army across at Bruinsburg; Grant moved at once three miles inland, and May 1st, beat Gen. Bowen at Port Gibson. Then he moved eastward, drove Johnston out of Jackson, an important center for railroad lines, and broke up all the communications in the neighborhood; then turning short about, he approached Vicksburg by forced marches; on May 10th met Pemberton at Champion Hills and defeated him; followed him sharply up, forced the passage of the Big Black, drove Pemberton into the city, and on May 16th had formed his lines of attack. After a vigorous siege, whose progress attracted the attention of the whole civilized world, the place surrendered with 27,000 men, on July 4th, 1863. The whole number of prisoners made since crossing the Mississippi was 37,000. This great achievement freed the Mississippi, cut the rebellion in two, and rendered it out of the question for the rebels to hold the Mississippi Valley. The taking of Vicksburg was remarkable, not so much as a successful engineering attack against earthworks, as it was when considered as the culmination of a well planned campaign. The place was in fact taken a good ways away from it. Grierson's wide destruction of the railroads and bridges, and the far wider fright which he spread among the rebels, were part of the fatal preliminaries which were the most decisive parts of the attack. Such were also the series of battles which so relentlessly pounded Pemberton backwards into the trap where he was finally caged; particularly the expulsion of the rebel forces from Jackson, just before the siege. All these operations gradually fixed Pemberton where he could not get out, and where his friends could not help him out; and so he waited until he had no more provisions, and then gave up. There seems no reason for believing that the assault which Grant had arranged to give on the 6th, if the surrender had not been made on the 4th, would have been more successful than either of the previous assaults; the earthworks of Vicksburg were skillfully and strongly built, and were much the stronger because they stood on ground itself naturally very strong. The great feature of the transaction was therefore the broad and far-seeing wisdom of a general who can organize campaigns, rather than the mere ability of a colonel to make a furious assault at the head of his regiment. That this was the nature of the campaign, appears from the history of the preliminary part of