Much as the men were suffering, the animals of the camp were in no better condition. The horses were weakened by lack of food and by the hardships of the recent days. As if these facts were not sufficient to make the general hesitate, it is said that his supplies of ammunition also were deficient, and that he was as seriously troubled by this last fact as by both of the others combined. But, like every successful man, General Lee decided not to think so much of what he did not have as of what he did have. Whatever might befall his attempt, he was confident that he would be able to make the Northern armies remain so long and so far from the protection of their defenses that he could draw out the campaign and there would be no fresh attempt to take Richmond before the following spring. This opportunity, as we know, would be seized by the defenders of Richmond to strengthen their defenses. At this time Lee was not expecting to receive any reinforcements, as the campaigns in Tennessee and Kentucky demanded all the men that could be spared. Between the 4th and 7th of September (1862) the Confederate troops were crossing the Potomac. On the last-named day General Jackson occupied Frederick city and speedily was followed by another division. Then the dashing cavalry of Stuart spread out in the State in such a manner that most of the attempts of the Union generals to gain information concerning the plans of their enemies were frustrated. Meanwhile, as we know, the Federal soldiers were holding three fortified places in or near the Shenandoah Valley which was the chief reliance of General Lee for his supplies. About eight thousand men had been stationed at Harper's Ferry, and there also were small garrisons at Martinsburg and at Winchester. As has been said, General McClellan urged General Halleck to recall these men and attach them to the Army of the Potomac. This is exactly what General Lee believed would be done, because it was what he himself would have decided upon if he had been in his opponent's position. When General Halleck decided to leave these garrisons in the Valley, Lee instantly decided that they must be taken, and he believed also that they could be captured easily. It was essential for the plans he had formed that his own communications with his base of supplies should not be threatened by such a large garrison as had been placed in Harper's Ferry. Acting promptly, as he usually did, General Lee now decided to divide his army and reunite the divisions west of the mountains before a decisive battle could be fought. With this purpose in his mind the commander of the Confederate troops issued his orders on the 9th of September, and on the following day General Jackson, in command of three divisions, after he had crossed the mountains, was to ford the Potomac at some place west of Harper's Ferry and then move upon the little garrison at Martinsburg.