[Indorsement.]

MAJOR: If Captain Hobbs should be ordered to report to me for a few days I am confident he can do good service. There are a great many absentees in Lee and Scott from Sixty-fourth Virginia and Edmundson's battalion.

Respectfully, &c.,

A. S. VANDEVENTER,

Colonel.

OCTOBER 7-11, 1864.-Operations in Montgomery County, Md.

Report of Brigadier En. Erastus B. Tyler, U. S. Army, commanding First Separate Brigade, Eighth Army Corps.

HDQRS. FIRST SEPARATE BRIGADIER, EIGHTH ARMY CORPS, Relay House, October 13, 1864.

SIR: I have the honor to submit the following report of the movements of the troops of my command since I received information of the presence of guerrillas in Maryland:

On the 7th instant I was informed by department headquarters that a small body of guerrillas had made their appearance at Sandy Springs, Montgomery County. I at once ordered Lieutenant-Colonel Knight, commanding First Delaware Cavalry, to proceed with his command to Sandy Springs to intercept them. Order were also given Smith's Independent Company Maryland Cavalry to proceed to same point and report to Colonel Knight for the purpose of thoroughly scouring that whole country.

On the 8th instant orders were received from Major-General-Haleck, thought department headquarters, to send all the mounted forces toward Rockville-to call them in from all points for this purpose; also to send Rank's battery (H), third Pennsylvania Artillery, which had for guns at Monrovia, to join the other forces and to cover the Washington Mosby with 800 men had crossed at Snicker's Gap and was about to make a raid into Maryland. These orders were complied with and the troops concentrated at Rocville.

On the 11th instant, at 5 p. m., I was informed by department headquarters that a telegram from Major-General Halleck had been received stating that Mosby had not crossed the Potomac and probably would not, aut that my forces should remain in the field for the present, and that I should be left free to move as I might deem best against any guerrillas I might hear of. Immediately upon receipt of this order Colonel Knight was directed to order Rank's battery to Monrovia and to scour the country thoroughly between the railroad and Potomac; to arrest all persons that could not satisfactorily account for themselves; to have his men instructed so as to concentrate them rapidly at any point, and to report as often as possible to these headquarters. All of which was complied whit as promptly as time and distance would permit.

I would respectfully state that the southern boundary of my command is described in orders as being on a straight line drawn from mouth of Monocacy River to Annapolis Junction, passing through Barnesville, Middlebarook, and Mechanicsville. The country south of this line and north of the Potomac is included in the Department of Washington. I have never been informed of the withdrawal of the forces