[Inclosure A.

UNITED STATES MILITARY TELEGRAPH,

Centreville, October 3, 1863-2. 30 p. m.

(Received 3. 40 p. m.)

Captain C. H. POTTER,

Assistant Adjutant-General:

The following is the disposition of the forces along the Orange and Alexandria Railroad:

The Fourth Delaware Infantry guards the road from Accotink to Sangster's, with headquarters at Fairfax Station, one company at Accotink, one company at Burke's, one on train, camp guards and pickets at Fairfax Station, 6 men at Hunter's Bridge, and small infantry and cavalry patrols on both sides of road. From Sangster's to Bull Run five companies of infantry guard the road, headquarters at Union Mills; one company at Bull Run Bridge, a platoon at Sangster's, pickets on three roads leading to Union Mills, and patrols moving along the railroad as far as Sangster's at irregular hours. The officers in command are active and vigilant.

RUFUS KING,

Brigadier-General.

[Inclosure B.]

HEADQUARTERS DEPARTMENT OF WASHINGTON,
OFFICE OF CHIEF QUARTERMASTER,

Washington, D. C., October 2, 1863.

Lieutenant Colonel J. H. TAYLOR,

Chief of Staff, and Assistant Adjutant-General:

COLONEL: In reply to your inquiries of this date, I have the honor to report that the first intimation I ever had of the intention of the military authorities to construct block-houses for the defense of railroad bridges was conveyed to me through the general commanding this department and the Quartermaster-General. These orders were to construct a block-house at every bridge on the Loudoun and Hampshire and Orange and Alexandria Railroads within the limits of this department, and were received by me some time between the 1st of 6th days of June last. My understanding of the matter at that time was that the Engineer Department had been some time previously intrusted with the work of placing the bridges in a defensive condition, but that in consequence of the delay in executing this duty, the Quartermaster-General decided to adopt my suggestion of placing the matter in my hands, with orders to do the work at once, according the matter in my hands, with orders to do the work at once, according the plans then in possession of the Engineer Department, which plans subsequently reached me through Major-General Heintzelman. After receiving the orders referred to, I provided the necessary timber for the work, but in consequence of the withdrawal of the troops from our front by General Hooker, the railroads were left in a totally unguarded condition, and the trains ceased running, thus rendering it impossible for me to continue my operations. When the Army of the Potomac returned to its former position in Virginia, I made every effort to procure trains to transport my timber lying along the Orange and Alexandria Railroad near Burke's Station to the specific points, but in consequence of the road being worked to its utmost capacity in transporting supplies, &c., to General Meade's forces, the superintendent, Mr. Devereux