MITCHELL'S,

September 18, 1863.

General MEADE:

I do not know how much the Rapidan has risen. In the present condition of occupancy none of us can visit the river. I refer to the Valleys of both the Rapidan and Robertson's River as being free from mountains and large streams as the cause of our being able to turn the enemy's left flank.

G. K. WARREN,

Major-General.

HEADQUARTERS FIRST ARMY CORPS,
September 18, 1863.

Major-General HUMPHREYS,

Chief of Staff, Army of the Potomac:

1. I moved from Rappahannock via Brandy Station. A portion of my command came directly across the country from Brandy Station to near Pony Mountain, the remainder of my column by Stevensburg.

2. There is a road from here to Stevensburg, and from there to Kelly's Ford.

3. Am not acquainted with any roads from the Rappahannock to the Rapidan between Rappahannock Ford and Kelly's Ford. Mountain Creek in front of my present position is impassable since the rain, except at one point, Stevensburg. I have ordered a bridge constructed over it, which will not be completed before to-morrow night, if then, finding it very difficult to get material to construct it with.

Very respectfully, your obedient servant,

JOHN NEWTON,

Major-General, Commanding.

P. S. -Have not heard of the condition of the roads since the rain.

CLARKSBURG,

September 18, 1863.

Brigadier-General AVERELL:

Colonel Mulligan reports again this morning that he has information, which he deems reliable, that an attack on him at Petersburg at an early date is contemplated. It is to be Jones', Imboden's, Jenkins', and Jackson's forces combined. What is your information? Is Jackson yet in Pocahontas? Do you think Jones' force is yet in Greenbrier?

Captain Hall, of the Sixth [West] Virginia Infantry, who is scouting Tucker County, reports that there are no pickets or scouts on the Seneca road, at Soldier White's, the Burnt House, or Wyant's. You should keep pickets or scouts constantly on that road watching those points.

[B. F. KELLEY,]

Brigadier-General.