At three o'clock Thursday morning, 26th instant, General Jackson will advance on the road leading to Pale Green Church, communicating his march to General Branch, who will immediately cross the Chickahominy, and take the road leading to Mechanicsville.

As soon as the movements of these columns are discovered, General A.P.Hill, with the rest of his division, will cross the Chickahominy near Meadow Bridge, and move direct upon Mechanicsville.

To aid his advance, the heavy batteries on the Chickahominy will at the proper time open upon the batteries at Mechanicsville.

The enemy being driven from Mechanicsville, and the passage across the bridge opened, General Longstreet, with his division and that of General D.H.Hill, will cross the Chickahominy at or near that point--General D.H.Hill moving to the support of General Jackson, and General Longstreet supporting General A.P.

Hill--the four divisions keeping in communication with each other, and moving in _echelon_ on separate roads, if practicable; the left division in advance, with skirmishers and sharp-shooters extending in their front, will sweep down the Chickahominy and endeavor to drive the enemy from his position above New Bridge; General Jackson, bearing well to his left, turning Beaver Dam Creek, and taking the direction toward Cold Harbor.