Thirteen months later, after McClellan's retreat from Richmond, was fought in almost the same place, on August 29 and 30, 1862, the second battle of Bull Run. General Pope had a considerable force in Northern Virginia, and when McClellan, whom Pope superseded, retreated from before Richmond, and started on his return from James River, Lee moved nearly his whole army up from Richmond, hoping to fall upon Pope before McClellan could join him. On August 22d the opposing forces confronted each other along the Rappahannock, when General Stuart, with the Confederate cavalry, made a raid around Pope's lines to the rear, reaching that general's headquarters and capturing his personal baggage, in which was his despatch book describing the position of the whole Northern army. This gave Lee such valuable information that on the 25th he sent Stonewall Jackson with thirty thousand men, who, by a forced march, went around the western side of the Bull Run Mountains, came east again by the Thoroughfare Gap, and on the night of the 27th was in Pope's rear, and had cut his railroad connections and captured his supplies at Manassas. Pope, discovering the flanking movement, began falling back towards Manassas, and Jackson then withdrew towards the Gap, waiting for Lee to come up. There were various strategic movements afterwards, with fighting on the 29th; and on the 30th the Confederate wings had enclosed as in a vise Pope's forces to the west of Bull Run, when, after some terrific combats, Pope retreated across Bull Run towards Washington. Pope had about thirty-five thousand men and Lee forty-six thousand engaged in this battle. During the night of September 2d Jackson made a reconnoissance towards Washington, in which the Union Generals Stevens and Kearney were killed at Chantilly, and the authorities became so apprehensive of an attack upon the Capital that they ordered the whole army to fall back behind the Washington defenses. Pope was then relieved, at his own request, and the command restored to McClellan. The Confederates marched northward across the Potomac and McClellan followed, ending with the battles of South Mountain and Antietam, later in September, when Lee retreated and recrossed the Potomac into Virginia on the 18th. The significant result of this conflict and withdrawal was the issue of the famous Emancipation Proclamation. President Lincoln had made a vow that if Lee was driven back from Maryland he would issue a proclamation abolishing slavery, which was done September 22, 1862. FREDERICKSBURG AND THE WILDERNESS.