By this strategy Lee had managed to detain 65,000 Federals in the Valley, and 20,000 or 30,000 more in and around Washington, whose fighting force must otherwise have been added to McClellan's already superior army before Richmond. Then he had managed to have Jackson suddenly and secretly quit the Valley, with the force that had there achieved such spectacular results, together with the troops that had been ostensibly sent to reinforce him for an aggressive campaign and by a rapid movement to join the army at Richmond and assist it in a supreme endeavor to dislodge McClellan. The situation then was this: Relying upon a reinforcement of 40,000 men under McDowell, McClellan had dangerously divided his army, keeping about half of it north and about half of it south of the Chickahominy river. His desire was to press forward his siege operations on the east of the Confederate capital and at the same time to maintain a threatening force north of the city. It was his purpose so soon as McDowell should add his 40,000 men to this army on the north, to sweep forward with the combined forces and irresistibly to push a conquering column into Richmond. But Lee had baffled all these plans by his masterful strategy. He had compelled the diversion of McDowell to the Valley, and while the authorities at Washington were nervously expecting Jackson to swoop down upon that city, Jackson with his whole force, which had slipped out of the Valley, suddenly appeared at Ashland, about a dozen miles northwest of Richmond and immediately upon McClellan's right flank. In the meanwhile Lee had sent Stuart--perhaps the most daring and enterprising of the Southern cavalry leaders--with a body of 1,200 or 1,500 horsemen and two guns, to the rear of McClellan's position, there to find out the disposition of troops, the condition of the roads and bridges, and whatever else might open the way to that gigantic operation of offensive defense which Lee intended presently to undertake. Stuart moved promptly into McClellan's rear and swept around it like a whirlwind. Finding that a tardy resistance was taking the form of an organized effort to cut off his retreat by the route over which he had come, the gaily enterprising cavalier of the South, instead of turning back and trying to retrace his steps as his enemy expected him to do, decided to ride on all the way around McClellan's army and thus spectacularly to emphasize the imperfection of McClellan's precaution for the protection of that rear which Lee was planning presently to assail tempestuously. He rode completely around McClellan, crossing his line of communications, rebuilding a bridge which had been destroyed for the purpose of cutting him off and entrapping him, and returning to Richmond with a loss so small as to be scarcely worthy of mention in an official report.