WASHINGTON, December 24, 1863.

Colonel ALEXANDER:

Major-General Meade has decided to relieve, by a detachment from the Pennsylvania Reserves, the guard from your command now at Bull Run bridge. When the changes is made, employ the guard relieved in strengthening the most important posts on the road between Fairfax Station and Bull Run bridge. Investigate and report the rumor that the four vedettes were captured and hung by guerrillas yesterday, near Flint Hill.

J. H. TAYLOR,

Asst. Adjt. General, and Chief of Staff.

FORT MONROE, VA., December 24, 1863.

(Received 11.40 a.m.)

General THOMAS,

Adjutant-General, U. S. Army:

Secretary of War's dispatch announcing Averell's return received. The dispatch assigning Point Lookout, Accomac and Northampton to this command was received. General Butler left yesterday for Point Lokout. Will return to-night.

J. W. SHAFFER,

Colonel, and Chief of Staff.

HDQRS. FIRST ARMY CORPS, ARMY OF THE POTOMAC, December 25, 1863.

Brigadier General S. WILLIAMS,
Asst. Adjt. General, Army of the Potomac:

GENERAL: I cannot conceal my astonishment that General Merritt should have reported to headquarters that "General Newton tells me he does not know what is expected of him," a sentence calculated to give an entirely wrong interpretation to my views. All the specifications of Special Orders, 331, and circular of December 22, were carried out. The picket line was established, and one division sent to the neighborhood of Mitchell's Station yesterday. The brigade directed to advance close on to Mitchell's Station may not yet have done so, but its commanders conferred with the officer commanding cavalry here (as directed),and if it has not, the fault is not with the infantry. The brigade of infantry and the cavalry were by the order to advance at the same time. The cavalry division starting out this morning were ordered back.

It will thus be seen that I clearly comprehended the instructions given me, and have acted on them to the utmost of my power. The only sense in which I am ignorant of the object of my being sent here is this, that I am uncertain whether out coming here is a premonitory sign of an advance against the enemy, or whether it is intended as a precaution against his advance. I think General Merritt has been led into his mistake by the expression of some such views as the above on my part.

Very respectfully, your obedient servant,

JOHN NEWTON,

Major-General, Commanding.