The main column pushed on towards Vicksburg, and found the rebels posted on a bridge over the Big Black. They had a line of intrenchments, defended by a garrison of four thousand men, with twenty guns. As soon as the pursuing army came up with this formidable obstacle in its path, the line was formed, and a heavy fire opened upon the works, which were finally carried by storm. Our men fought bravely, and the Confederate line broke and fled like sheep. In their terror the rebels on the opposite side of the river set their end of the bridge on fire, before half their force had crossed. The demoralized wretches fled to the river, and attempted to escape by swimming. The fire of the cannon was turned upon them, and the stream was crimsoned with their blood. Seventeen hundred and fifty prisoners, eighteen guns, and five standards were captured in this lively battle. Bridging the river, Grant pushed on towards Vicksburg, uniting with Sherman, who came by a more northerly route. The two generals rode together to the farthest height, which looked down upon the Yazoo. The high ground they had longed to possess had been reached, and it was to them the promised land. They were elated at the prospect, and Sherman acknowledged that, until this moment, he had not deemed the movement a success. In just twenty days Grant had marched over two hundred miles, fought five distinct battles, captured eighty-eight pieces of ordnance, and deprived the enemy of the services of thirteen thousand soldiers. He had destroyed the railroad, captured Jackson and Grand Gulf. Never was so brief a campaign productive of such successes. As Sherman congratulated him upon the splendid results he had achieved, he quietly smoked his cigar, but made no vain-glorious reply--no reply at all. Vicksburg was immediately invested by a line which extended from the river above to the river below the town. The coveted base of supplies was obtained. Pemberton had thirty thousand men--a number fully equal to that of the besiegers--with two hundred cannon. On the 18th of May Johnston advised him that Vicksburg could not be held without Haines's Bluff, and recommended him to save his troops by withdrawing; but Pemberton decided, with the advice of his officers, to remain. Grant's men were flushed with victory, and desired to storm the works. They were permitted to do so as soon as the line of investment was completed. A heavy attack was made all along the intrenchments, but it was not crowned with success.