BELLE PLAIN, May 16, 1864.

(Received 1`1.30 a. m.)

Honorable E. M. STANTON, Secretary of War:

SIR: I have the honor to report that we have communication with Washington i less than two hours. Sent forward mounted couriers with dispatch to Lieutenant-General Grant this 3 a. m. Several barges and four or five steamers arrived last night; nothing else of importance transpired here. Steamer Spaulding is loading with prisoners, per tug Belger, at 8.30 a. m.

Very respectfully, &c.,

A. D. COLLINS,

Captain, &c.

BELLE PLAIN, May 16, 1864.

(Received 9 p. m.)

Honorable EDWIN M. STANTON, Secretary of War:

SIR: I have the honor to request instructions relative to the following interrogatory: Have I the right that is delegated to operators, viz, to acquaint myself with contents of dispatches, or so much of them as to enable me to order the mounted couriers to take the trot or gallop? The following steamers departed at noon: New Jersey, S. R. Spaulding, with prisoners for Point Lookout. Arrived since 6 p. m., George Washington, Thomas Jefferson, Lizzie Baker, with troops and horses. The service of the Diamond are no longer required. The line will be complete to this point by morning.

Very respectfully,

A. D. COLLINS,

Captain, Veteran Reserve Corps.

HEADQUARTERS,
Belle Plain, Va., May 16, 1864.

Colonel E. SCHRIVER, Military Governor, Fredericksburg:

General Abercrombie wishes you would dispatch a messenger from your headquarters to this place at 6 a. m. and 12 noon, so that constant communication can be kept up. Any message from General Grant, of course, will come by special messenger. There is a telegraph line for official dispatches at a point 6 miles below this place, but we send all dispatches from this place by boat to telegraph station. Please inform me in your next whether your get a countersign from the Army of the Potomac.

I have the honor,

R. L. ORR,

Captain and Acting Assistant Adjutant-General.

BALTIMORE, MD., May 16, 1864-2 a. m.

(Received 2.10 a. m.)

Major General H. W. HALLECK, Chief of Staff:

The One hundred and sixty-third Ohio Militia left for Washington before your dispatch was received. Can it be returned immediately? General Lockwood and his troops will be at once forwarded.

LEW. WALLACE,

Major-General.