I caused a few rounds to be fired yesterday from the Rhode Island section rifled 6-pounders, and find that with guns of that class we can reach the outworks of Leesburg.

The Fifteenth Massachusetts Regiment joined this command yesterday morning.

Very respectfully, I am, major, your most obedient servant,

CHAS. P. STONE,

Brigadier-General, Commanding.

HEADQUARTERS GENERAL BANKS' DIVISION,
Near Darnestown, Md., August 31, 1861.

General STONE:

SIR: Major-General Banks directs me to inform you that he arrived at this place day before yesterday. He requests that you will at your earliest convenience send him, by some responsible agent, some information as to your pickets, their posts, the position of your main body, &c., and that you will communicate to him any information in your possession concerning the positions, numbers, &c., of any troops which my be between Darnestown and Washington. He requests that you will order the section of the Rhode Island Battery now with you to join him at your earliest convenience.

Very respectfully, your obedient servant,

ROBT. WILLIAMS,

Assistant Adjutant-General.

HEADQUARTERS CORPS OF OBSERVATION,
Poolesville, September 2, 1861.

Major S. WILLIAMS,

Assistant Adjutant-General, Hdqrs. Army of the Potomac:

MAJOR: I have the honor to report that two or three regiments broke up their camp near Leesburg this forenoon, and marched nearer the river, the bulk of two regiments approaching Conrad's Ferry. They strengthened all their pickets throughout the line. There is no appearance of re-enforcement.

My impression is that the movement was caused by a feeling of alarm lest we should attempt a crossing in force, as one of he advanced pickets of the Tammany regiment crossed the river last night and cut out and brought over a large ferry-boat.

I have caused the outposts to be strengthened by infantry and artillery, but do not anticipate any advance of the enemy.

Very respectfully, I am, your obedient servant,

CHAS. P. STONE,

Brigadier-General, Commanding.

CAMP NEAR DARNESTOWN, September 4, 1861.

Honorable SIMON CAMERON, Secretary of War, &c.:

SIR: I visited the Potomac at Edwards Ferry, opposite Poolesville, last evening. There are no indications of movement more than for a month past. Their force at Leesburg appears to be about three or four regiments. Two or 3 miles from the river they have thrown up a slight