Numbers 2. Reports of Brigadier General Charles P. Stone, U. S. Army, with orders.

HEADQUARTERS CORPS OF OBSERVATION,
Poolsville, October 19, 1861.

GENERAL: The following is the substance of information derived from an intelligent mulatto teamster, who deserted from the Thirteenth Mississippi regiment, near Leesburg, and came in last night; was brought before me to-day.

Was at Manassas last week, Tuesday; went there to get a load of pickled pork, which came by railroad from Mississippi. At Manassas saw a great many fortifications; most of them built of bags of sand, some built of rails, with dirt thrown up in front. Saw a great many guns, all iron, rounded off like at the butt; saw as many as fifty of these guns; great many soldiers drilling them. They were expecting a fight at fairfax Court-House and at Leesburg. He was at Fairfax Court-House on Tuesday last for a load of flour. They were then expecting an immediate attack there and were sending off large quantities of stores to Manassas. Went into the office with the wagon master to get a pass, and saw in another part of the room two gentleman, said to be General Beauregard and General Davis. He described Beauregard accurately and Davis' face. He got back to Goose Creek on Wednesday afternoon. On Wednesday night there was an alarm that General Stone was crossing the river and the trains were all brought from Leesburg to Goose Creek; that he heard them say all the heavy baggage was in the trains and that the troops would fight at Leesburg, and then, if defeated, fall back to Widow Carter's Mill, below Goose Creek, where they would make another stand, and if defeated there they would fall back to Manassas; that the wagons were all kept ready to start for Manassas. He says they have near Leesburg four brass cannons, some rifled, drawn by four horses each; the ammunition carried in two-horse wagons. He says the railroad bridge on Goose Creek has not been rebuilt; and that the track is torn up for 3 miles south of the burnt bridge. States that General Evans is in command at Leesburg and Colonel Barksdale is in command of the Thirteenth Mississippi Regiment, to which he was attached as teamster.

I believe the fellow's story. The evidences of the alarm he mentions were apparent, and it was probably induced by my strengthening the force on Harrison's Island and making use of a large flat-boat there. The place he mentions as the second for a stand (Mrs. Carter's Mill) is a strong position about 1 mile from Aldie, on the road from Leesburg to Gum Spring. The wagon trains rendezvous near that point.

I send herewith the Richmond Dispatch for Tuesday and Wednesday last, which was procured by our pickets on Harrison's Island this afternoon.

I have prepared slight entrenchments on Harrison's Island capable of covering several hundred men; sufficient to cover an advance of a considerable force to the island, and to hold it for an hour or two in spite of any artillery which might be placed on the commanding ground on the Virginia side.

Very respectfully, your obedient servant,

CHAS. P. STONE,

Brigadier-General, Commanding.

Major General GEORGE B. McCLELLAN,

Commanding Army of the Potomac.