WAR DEPARTMENT, Washington, June 24, 1863-10. 35 p. m.

Major-General SCHENCK, Baltimore, Md.:

Your attention is particularly called to the importance of guarding the railroad bridges as the Monocacy and near Elysville against a raid. Should the enemy appear in large force, these guards can readily be drawn back. General Hooker will cover to Harper's Ferry, and communicate directly with the garrison. He is authorized by the President to give orders to your command.

H. W. HALLECK.

Baltimore, June 24, 1863-3. 05 p. m.

Brigadier-General BRIGHS, Relay House:

While the general commanding sends the Sixth New York [Militia] Infantry to defend the Monocacy Bridge, he expects General Briggs to take care of Elysville and other exposed points on the railroad this side of the Monocacy. By order of Major-General Schneck:

DONN PIATT,

Chief of Staff.

Baltimore, June 24, 1863.

Brigadier-General BRIGGS, Relay House, Baltimore and Ohio Railroad: How many infantry can you send immediately, if transportation be furnished to you, as a strong and further guard to Monocacy Bridge and to Elysville? You will also have a section of a battery supplied for the Monocacy.

DONN PIATT.

Lieutenant-Colonel, and Chief of Staff.

MARYLAND HEIGHTS, June 24, 1863.

(Received 2. 30 p. m.)

H. W. HALLECK,

General-in-Chief:

Our pickets have just brought in two prisoners from the Eighteenth Georgia Regiment, McLaws' division, of Longstreet's corps, who confirm that Longstreet is crossing the Potomac at Shepherdstown.

DAN. TYLER,

Brigadier-General.

Baltimore, MD., June 24, 1863-3. 40 p. m.

H. W. HALLECK,

General-in-Chief:

The following dispatch has just been received from the officer in command of the block-houses at the Monocacy: My scouts are in. Have been through Middletown. Report no rebels this side of Boonsborough. Large bodies of men of all arms are moving north through Hagerstown. The Mercersburg school is here to take the train. Report that Ewell and Hill passed through Hagerstown yesterday.

ROBT. C. SCHENCK,

Major-General.