Stonewall Jackson, if not Lee's ablest lieutenant, was certainly his swiftest, and the one that threw the most uncertainty into the game by his rapid movements and unexpected appearances. At a later stage of the war his erratic strategy, if persisted in, would probably have brought his famous corps of "foot cavalry" (as they were called from their quick marches) to sudden destruction. An opponent like Sheridan, who knew how to be swift, brilliant, and audacious, without transgressing the fundamental rules of warfare, would have been likely to finish him at a blow. But Jackson did not live to meet such an opponent. At this time the bugbears that haunt imaginations not inured to war were still in force, and the massive thimble-rigging by which he was made to appear before Richmond, and presto! sweeping down the Shenandoah Valley, served to paralyze large forces that might have been added to McClellan's army. The topography of Virginia is favorable to an army menacing Washington, and unfavorable to one menacing Richmond. The fertile valley of the Shenandoah was inviting ground for soldiers. A Confederate force advancing down the valley came at every step nearer to the National capital, while a National force advancing up the valley was carried at every step farther away from the Confederate capital. The Confederates made much of this advantage, and the authorities at Washington were in constant fear of the capture of that city. {153} [Illustration: BURNING OF STORES AND MUNITIONS OF WAR AT WHITE HOUSE, VA.--DEPARTURE OF THE FEDERAL FLOTILLA FOR THE JAMES RIVER.] Soon after Stuart's raid, Lee began to make his dispositions to attack McClellan and drive him from the peninsula. He wrote to Jackson: "Unless McClellan can be driven out of his intrenchments, he will move by positions, under cover of his {154} heavy guns, within shelling distance of Richmond." To convey the impression that Jackson was to move in force down the valley, Lee drew two brigades from his own army, placed them on the cars in Richmond in plain sight of some prisoners that were about to be exchanged, and sent them off to Jackson. Of course the released prisoners carried home the news. But Jackson returned with these reinforcements and Ewell's division of his corps, joined Lee, and on the 25th of June concerted a plan for immediate attack. Secretary Stanton appears to have been the only one that saw through the game; for he telegraphed to McClellan that while neither Banks nor McDowell nor Frémont could ascertain anything about Jackson's movements, his own belief was that he was going to Richmond. Yet the impression was not strong enough in the mind of the Secretary of War (or else the Secretary could not have his own way) to induce the appropriate counter-move of immediately sending McDowell's whole corps to McClellan. McCall's division of that corps, however, had been forwarded, and on the 18th took a strong position on McClellan's extreme right, near Mechanicsville.