The plan was an improvement upon Rosecrans's in arranging for a progressive concentration of his forces into one column led by himself; but it would probably have failed, first, from the impossibility of supplying the army on the route, and second, because the railroads east of the mountains ran on routes specially well adapted to enable the enemy quickly to concentrate any needed force at Staunton, at Lynchburg, at Christiansburg, or at Wytheville, to overpower the column. The Union army would be committed to a whole season of marching in the mountains, while the Confederates could concentrate the needed force and quickly return it to Richmond when its work was done, making but a brief episode in a larger campaign. But the plan was not destined to be thoroughly tried. Stonewall Jackson, after his defeat by Kimball at Kernstown, March 23d, had retired to the Upper Shenandoah valley with his division, numbering about 10,000 men; Ewell, with his division, was waiting to co-operate with him at the gaps of the Blue Ridge on the east, and Edward Johnson was near Staunton with a similar force facing Milroy. In April General N. P. Banks, commanding the National forces in the Shenandoah valley, had ascended it as far as Harrisonburg, and Jackson observed him from Swift-Run Gap in the Blue Ridge, on the road from Harrisonburg to Gordonsville. Milroy also pushed eastward from Cheat Mountain summit, in which high region winter still lingered, and had made his way through snows and rains to McDowell, ten miles east of Monterey, at the crossing of Bull-Pasture River, where he threatened Staunton. But Banks was thought to be in too exposed a position, and was directed by the War Department to fall back to Strasburg. On the 5th of May he had retired in that direction as far as New-Market. Blenker's division had not yet reached Fremont, who was waiting for it in Hardy County at Petersburg. Jackson saw his opportunity and determined to join General Johnson by a rapid march to Staunton, to overwhelm Milroy first, and then return to his own operations in the Shenandoah. Moving with great celerity, he attacked Milroy at McDowell on the 8th, the latter calling upon Fremont for help. Schenck was sent forward to support him, and reached McDowell after marching thirty-four miles in twenty-four hours. Jackson had not fully concentrated his forces, and the Union generals held their ground and delivered a sharp combat in which their casualties of all kinds numbered 256, while the Confederate loss was 498, General Johnson being among the wounded. Schenck, as senior, assumed the command, and on the 9th began his retreat to Franklin, abandoning the Cheat Mountain road. Franklin was reached on the 11th, but Jackson approached cautiously, and did not reach there till the 12th, when, finding that Fremont had united his forces, he did not attack, but returned to McDowell, whence he took the direct road to Harrisonburg, and then marched to attack Banks at Strasburg, Ewell