The situation of the rival armies on the night of the twenty-seventh forms one of the curiosities of war. Jackson was concentrating round Manassas Junction. Lee was following Jackson's line of march, but was still beyond Thoroughfare Gap. Between them stood part of Pope's army, the whole of which occupied an irregular quadrilateral formed by lines joining the following points: Warrenton Junction, Bristoe Station, Gainesville, and Thoroughfare Gap. Thirty miles northeast were the twenty thousand Federals who joined Pope too late. Thirty miles southeast the rear of McClellan's forces were still massing at Aquia. In Pope's opinion Jackson was clearly trapped and Lee cut off. But when Pope began to close his cumbrous net the following day Jackson had disappeared again. Orders and counter-orders thereupon succeeded each other in bewildering confusion. McClellan could be left out: and a very good thing too, thought Pope, who wanted the victory all to himself, and whose own army greatly outnumbered Lee's and Jackson's put together. But Washington was nervous again; it contained the reinforcements; and it had suddenly become indispensable to Pope as an immediate base of supplies now that the base at Manassas had been so completely destroyed. Pope's troops therefore mostly drew east during the twenty-eighth, forming by nightfall a long irregular line, facing west, with its right beyond Centreville and its extreme left held by Banks's mauled divisions south of Catlett's Station. Meanwhile Jackson had slipped into place in the curve of Bull Run, facing southeast, with his left near Stone Bridge, his back to Sudley Springs, and his right open to junction with Lee, who was waiting for daylight to force the Gap against the single division left there on guard.