3. The Third Corps will follow the Fifth Corps, and take post at the brigade on the Antietam. It may be called on to move either to the support of the Fifth or Sixth Corps.

4. The Sixth Corps, followed by the First Corps, will proceed along the Hagerstown pike, and take position on the north side of Beaver Creek.

5. The Eleventh Corps will take post on the northwest side of Boonsborough, and be held in readiness to support the other corps.

6. The Reserve Artillery will take post on the west side of Boonsborough.

7. Corps commanders will keep themselves in communication with the columns ont the right and left, and be prepared to move forward if the developments of the day should require.

8. Headquarters will be near the position of the Third Corps to-morrow night. During the movement to-morrow they will be as at present established.

By command of Major-General Meade:

S. F. BARSTOW,

Assistant Adjutant-General.

CIRCULAR.] HEADQUARTERS ARMY OF THE POTOMAC,

July 9, 1863-2. 45 p. m.

Information obtained from reconnoitering parties and scouts indicates that the enemy is concentrating in our front to meet our attack. The commanding general therefore directs that, immediately on receipt of this dispatch, you will move up your corps to the immediate vicinity of the corps in your front, on the same road.

By command of Major-General Meade:

S. WILLIAMS,

Assistant Adjutant-General.

(For information of Major-General Sedgwick.)

HEADQUARTERS SECOND CAVALRY BRIGADE, July 9, 1863-12. 30 p. m.

General HOWARD:

A heavy line of infantry, not less than a division, is advancing on the Harrisburg road; also a line in plain sight on our right, and working to our right front.

Respectfully,
THOS. C. DEVIN,

Colonel, Commanding.

HARPER'S FERRY, July 9, 1863-5 p. m.

General WARREN,

Acting Chief of Staff, Middletown:

I have three-years' troops, 1, 633; troops, term nearly out, 4, 150; cavalry, 280; Eighth New York Heavy Artillery, 70; three light bat-