Army of the Potomac. General Pleasonton, at 9 a. m., was at Racoon Ford, on the Rapidan. The enemy's cavalry and a battery of artillery held the opposite bank.

F. C. NEWHALL,

Captain, of Pleasonton's Staff.

GEO. G. MEADE,

Major-General.

CIRCULAR.] HEADQUARTERS ARMY OF THE POTOMAC,

September 14, 1863-9. 45 p. m.

Commanding Officer Eleventh Corps:

The commanding general desires me to make known to you the existing condition of affairs. General Pleasonton has driven the enemy's cavalry and artillery across the Rapidan, but was unable, owing to finding infantry and artillery in position, to effect a crossing at Racoon, Somerville, or Mitchell's Fords (the railroad crossing). He now holds the north bank of the Rapidan, supported by the Second Corps at Culpeper Court-House. The rest of the army is in the positions formerly occupied. General Pleasonton has sent in 3 guns (2 3-inch and 1 12-pounder howitzer) and 120 prisoners. From the latter it is believed Longstreet's corps has gone south, but that Ewell and Hill are still behind the Rapidan prepared to dispute its passage.

The commanding general desires you to keep your command prepared to move at short notice, your trains supplied, and everything in readiness for an advance, which, from present appearances, will be the character of the movement, if any is made. This communication is confidential.

S. WILLIAMS,

Assistant Adjutant-General.

(To commanding officers First, Third, Fifth, Sixth, Eleventh, and Twelfth Corps.)

SEPTEMBER 14, 1863-9 p. m.

(Received 10. 30 p. m.)

Major-General HALLECK:

General Pleasonton reports that he has driven the enemy's cavalry and artillery across the Rapidan, and has to-day unsuccessfully attempted to force a passage at three points, Raccoon Ford, Somerville Ford, and Mitchell's Ford (at the railroad crossing), being at each point met by artillery in position, and rifle-pits manned by infantry.

General Gregg, at the railroad crossing, reports taking a prisoner of the Forty-eighth Mississippi Regiment, belonging to A. P. Hill's corps, who said the whole of Hill's corps was at or near Orange Court-House. Other prisoners taken yesterday aver that Ewell's corps is also behind the Rapidan.

My judgment, formed on the variety of meager and conflicting testimony, is, that Lee's army has been reduced by Longstreet's corps, and perhaps by some regiments from Ewell and Hill. What the amount of force left with him, it is difficult to conjecture, but I have no doubt it is deemed sufficient by him, with the advantages of position, to check my crossing the Rapidan, at least until he can withdraw, in case he desires to do so. Under these circumstances, I have