Outside the Confederate line ran the Federal line of investment. At the beginning of the siege the two lines were some hundreds of yards apart; as the siege went on the blue drew nearer, nearer. They drew so near at last that, at night, the grey and blue pickets conversed, so near that at places the several ramparts all but touched. Forty-three thousand had Grant at the formal opening of the siege; steadily as it progressed he brought across the river other thousands. By the middle of June he had seventy-five thousand, besides the fleet upon the river. Ninth Army Corps, Thirteenth Army Corps, Fifteenth, Sixteenth, Seventeenth Army Corps,—Grant drew his forces and to spare around the town and its all too meagre defences, its one hundred and two guns and small store of ammunition and its twenty-eight thousand combatants, three thousand of whom were in hospital. Besides the guns of the fleet, there were now two hundred and twenty blue guns in position. They never lacked for ammunition. Seven miles, from the river north of the town to the river south, ran the Confederate lines. Fifteen miles, from Haines’s Bluff to Warrenton, enclosing the Confederate, ran the Federal lines. Grant was strongly posted. He had wide, sheltered hollows in which to mass his men, and commanding ridge-tops on which to place his guns. His far-flung position was strong for offence, and equally strong, in case of an attack from without, for defence. All day and every day thundered the Federal artillery. All day and every day the grey lines and the grey town knew the rain of shells. Very early in the siege the blue prepared to mine. At Jackson, fifty miles to the east, was Joseph E. Johnston, slowly gathering troops. At the last and best he had only twenty-four thousand troops. Between him and the beleaguered place lay an army of seventy-five thousand men, strongly posted, and strong—where the grey were weakest—in artillery; with, also, a blue fleet in the background. At long intervals Pemberton got out a messenger to him; at long intervals one of his own got into Vicksburg. Within all these lines Vicksburg herself crouched and waited. All her people who might dwelled now in caves. They came out in the night or during the infrequent silences of the day and returned to the houses that were not injured. They grew careless about exposure, or rather they grew fatalistic after the manner of courageous, besieged places. They passed through the streets even when the shells were raining, or they wandered out toward the lines, or they sat under some already splintered tree and counted the gunboats on the dusky river. Courage stayed with them, and even at times gaiety, though she had a hectic cheek.