and take the enemy on his right flank and in reverse at Centreville. Difficulties, however, of an insuperable character, in connection with means of transportation and the marching condition of his troops, made this impracticable, and it was determined our forces should be united within the lines of Bull Run, and thence advance to the attack of the enemy.
General Johnston arrived here about noon on the 20th July, and being my senior in rank he necessarily assumed command of all the forces of the Confederate States then concentrating at this point. Made acquainted with my plan of operations and dispositions to meet the enemy, he gave them his entire approval, and generously directed their execution under my command.
In consequence of the untoward detention, however, of some five thousand of General Johnston's army corps, resulting from the inadequate and imperfect means of transportation for so many troops at the disposition of the Manassas Gap Railroad, it became necessary, on the morning of the 21st, before daylight, to modify the plan accepted to suit the contingency of an immediate attack on our lines by the main force of the enemy, then plainly at hand.
The enemy's forces, reported by their best-informed journals to be fifty-five thousand strong, I had learned from reliable sources on the night of the 20th were being concentrated in and around Centreville and along the Warrenton turnpike road to Bull Run, near which our respective pickets were in immediate proximity. This fact, with the conviction that after his signal discomfiture on the 18th of July before Blackburn's Ford-the center of my lines-he would not renew the attack in that quarter, induced me at once to look for an attempt on my left flank, resting on the stone bridge, which was but weakly guarded by men, as well as but slightly provided with artificial defensive appliances and artillery.
In view of these palpable military conditions, by 4.30 a.m. on the 21st of July I had prepared and dispatched orders directing the whole of the Confederate forces within the lines of Bull Run, including the brigades and regiments of General Johnston, which had arrived at that time, to be held in readiness to march at a moment's notice. At that hour the following was the disposition of our forces: Ewell's brigade, constituted as on the 18th of July, remained in position at Union Mills Ford, its left extending along Bull Run in the direction of McLean's Ford, and supported by Holmes' brigade, Second Tennessee and First Arkansas Regiments, a short distance to the rear-that is, at and near Camp Wigfall. D. R. Jones' brigade, from Ewell's left, in front of McLean's Ford and along the stream to Longstreet's position. It was unchanged in organization, and was supported by Early's brigade, also unchanged, placed behind a thicket of young pines a short distance in the rear of McLean's Ford. Longstreet's brigade held its former ground at Blackburn's Ford, from Jones' left to Bonham's right, at Mitchell's Ford, and was supported by Jackson's brigade, consisting of Cols. James F. Preston's Fourth, Harper's Fifth, Allen's Second, the Twenty-seventh Lieutenant-Colonel Echols, and the Thirty-third, Cummings' Virginia Regiments, two thousand six hundred and eleven strong, which were posted behind the skirting of pines to the rear of Blackburn's and Mitchell's Fords, and in rear of this support was also Barksdale's Thirteenth Regiment Mississippi Volunteers, which had lately arrived from Lynchburg. Along the edge of a pike thicket, in rear of and equidistant from McLean's and Blackburn's Fords, ready to support either position, I had also placed all of Bee's and Bartow's brigades that had arrived,