Numbers 49. [Received August 26, 1862, from near Waterloo Bridge, 3.45 p. m.] UNITED STATES MILITARY TELEGRAPH.

General POPE:

trains and troops still passing over the same route. A deserter, just come in, says Longstreet's corps, embracing Anderson's, Jones', Kemper's, Whiting's, and Evans' divisions, are located in the woods back of Waterloo Bridge. Thinks Hill's division at Jefferson; Jackson's corps somewhere above Longstreet's. He appears truthful, and I credit his story. The entire district form Jefferson to Culpeper, Sperryville, and as far as Barbee's, covered with smoke and lines of dust. The deserter reports the arrival last evening of the greater portion of Longstreet's corps at its present position.

JOHN S. CLARK,

Colonel and Aide-de-Camp.

Numbers 50. HEADQUARTERS THIRD CORPS, Warrenton, August 26-9 p. m.

Major-General POPE:

An intelligent negro has just come in to General Buford from White Plains, and reports the advance of the enemy at that place. He says he saw himself at White Plains to-day at 12 o'clock two batteries of artillery, two regiments of cavalry, four regiments of infantry, and that they were moving in the direction of Thoroughfare Gap. The man's story is evidently to be relied upon. General Buford says his statements are confirmed by his scouts, who report large trains passing up through Orleans to White Plains.

IRVIN McDOWELL,

Major-General.

Numbers 51. WARRENTON JUNCTION, August 26, 1862-8 p. m.

Major-General McDOWELL,

Warrenton:

Fitz John Porter, with Sykes' and Morell's divisions, will be within 2 1\2 miles of Warrenton, on the Fayetteville road, to-morrow night. See if you cannot have the cross-roads repaired, so he can get from his position into the Sulphur Springs road with his artillery if he should be needed. I will use all efforts to have Sturgis and Cox within 3 miles of you to-morrow night, and have requested General Halleck to push forward Franklin at once, carrying his baggage and supplies by railroad to the point where the Manassas Gap Railroad intersects the Warrenton turnpike. From that position he can either advance to your support or prevent your right from being turned form the direction of the Manassas Gap Railroad. I think our fight should be made at Warrenton, and if you can postpone if for two days everything will be right.

JNO. POPE,

Major-General, Commanding.