About this time I received information that the enemy was preparating a large force to drive back General Pope and attack either Washington or Baltimore. The information was so direct and reliable that I could not doubt its correctness. This gave me serious uneasiness for the safety of the capital and Maryland, and I repeatedly urged upon General McClellan the necessity of promptly moving his army so as to form a junction with that of General Pope. The evacuation of Harrison's Landing, however, was not commenced till the 14th, eleven days after it was ordered.

Greatly discouraged at the prospect of timely aid from that quarter, I authorized General Pope to order the main forces of General Cox in Western Virginia with all possible dispatch by railroad to join him via Washington.

To facilities the withdrawal of the Army of the Potomac from the Peninsula and gain time by a demonstration against the enemy, General Pope pushed his forces across the Rappahannock, occupied Culpeper, and threatened Gordonsville. Jackson's and Ewell's forces were hurried to the Rapidan, and on the 9th of August encountered Bank's corps at Cedar Mountain. A hard-fought battle ensued, and on the arrival of re-enforcements from the corps of McDowell and Sigel the enemy fell back upon the Rapidan and Gordonsville.

On the 15th our cavalry surprised a party of the enemy near Louise Court-house, and captured important dispatches, showing that Lee was moving by forced marches the main body of the rebel army to attack Pope before a junction could be formed between him and the Army of the Potomac.

On the 16th I telegraphed to General Pope not to cross the Rapidan, and advised him to take position in rear of the rappahannock, where he could be more easily re-enforced. He commenced this movement on the 17th, and by the morning of the 18th had most of his forces behind that river, prepared to hold its passes as long as possible. He had been re-enforced by King's division and a part of Burnside's corps, under General Reno, from Fredericksburg. I also directed General Burnside to occupy Richard's and Barnett's Fords, which were between him and General Pope's main army. The enemy made several attempts to cross at different points on the Rappahannock, but was always repulsed, and our troops succeeded in holding the line of this river for eight days. It was hoped that during this time sufficient forces from the Army of the Potomac would reach Aquia Creek to enable us to prevent any farther advance of Lee, and eventually with the combined armies to drive him back upon Richmond.

On the 24th he made a flank movement and crossed a portion of his forces at Waterloo Bridge, about twelve miles above the Rappahannock railroad station. Pope directed an attack upon the forces which had crossed the river, hoping to cut them off, but the enemy escaped with no great loss. The annexed telegram from General Pope, marked Exhibit Numbers 3,* dated the 25th, gives his views of the condition of affairs at that date. The enemy, however, had not fallen back, as he supposed, but on being repulsed at Waterloo Bridge had moved farther up the river and entered the valley which lies between the Blue Ridge and Bull Run Mountains. The object of this movement was evidently to get in Pope's rear and cut off his supplies from Washington. Anticipating this danger I had telegraphed to General Pope on the 23rd, "By no means expose your railroad communication

---------------

* See Series I, Vol. XII, Part II, p. 11.

---------------