Against this alert adversary Grant could now oppose about an equal number of men, comprised in four corps--the Thirteenth (McClernand), Fifteenth (Sherman), Sixteenth (Hurlbut), Seventeenth (McPherson). Hurlbut was of necessity retained at and near Memphis, to preserve communications and hold western Tennessee; the three other corps could take the field with about forty-three thousand. Among Grant’s lieutenants, two were soldiers of the best quality--Sherman and James B. McPherson, the latter a young officer of engineers, who during the preceding months had been coming rapidly to the front.[232] Besides the army, Grant had a powerful auxiliary in the fleet, which now numbered seventy craft, large and small, manned by fifty-five hundred sailors and commanded by David D. Porter, an indefatigable chief.
Grant at the outset could, of course, have no fixed plan. Throughout February and March his operations were tentative; and though the country murmured at his “inactivity,” never did general or army do harder work. Might not Vicksburg perhaps be isolated on the west, and a way be found beyond the reach of its cannon to that vantage-ground south of it which seemed so inaccessible? Straightway the army tried, with spade, pick, and axe, to complete the cut-off which Williams had begun the previous summer; also to open a tortuous and embarrassed passage far round through Lake Providence and the Tensas and Washita rivers. Might not some insufficiently guarded approach be found through the Yazoo bottom[233] to Haines’ Bluff, the height dominating Vicksburg from the northeast, which Sherman had sought to seize at Chickasaw Bayou? Straightway there were enterprises seldom attempted in war.[234] The levee at Yazoo Pass was cut, far up the river, so that the swollen Mississippi flooded the wide region below. Through the crevasse plunged gunboat and transport, to engage in amphibious warfare; soldiers wading in the mire or swimming the bayous; divisions struggling to _terra firma_, only to find that Pemberton was there before them behind unassailable parapets; gunboats wedged in ditches, unable to turn, with hostile axemen blocking both advance and retreat by felling trees across the channel; Porter sheltering himself from sharpshooters within a section of broken smokestack and meditating the blowing-up of his boats; Sherman now paddling in a canoe, now riding bareback, now joining the men of a rescue-party in a double-quick--all in cypress forests draped with funereal moss, as if Death had made ready for a calamity that seemed certain.