HEADQUARTERS SECOND CORPS,
March 18, 1864.

COMMANDING OFFICER CAVALRY CORPS:

The following just received:

Major-General HUMPHREYS,

Chief of Staff, Army of the Potomac:

Mr. Roebling has just returned from the Rapidan. No enemy on this side; only a few men, not more than 20, came over the river this morning, and all went back. Two shots were all the skirmishing.

G. K. WARREN,

Major-General, Commanding Second Corps.

A. A. HUMPHREYS,

Chief of Staff.

HEADQUARTERS FIRST CAVALRY DIVISION,
March 18, 1864-7 p. m.

[Colonel C. R. SMITH,

Chief of Staff, Cavalry Corps:]

COLONEL: Your communication just received. I have given Colonels Devin and Chapman orders this morning to explore the country constantly well out to the front of their positions toward Sperryville and James City. I will occupy Thoroughfare Mountain to-morrow with signal station, provided a signal officer is furnished. It will scarcely be safe with the force I can send (not more than 100 men) to occupy it for more than temporary observation each day. Understand, I can send more than 100 men to occupy it, but submit if the object obtained in occupying it permanently is sufficiently great to justify a greater reduction of my command by such detail. Please telegraph if this meets the major-general's approval. A party sent out in that way each day would serve the double purpose of a scout and protect the signal officer too. I think would be safe. Large fires are seen beyond us the west; some apparently beyond a spur of the mountains. I will send out force immediately.

Very respectfully, your obedient servant,

W. MERRITT,

Brigadier-General of Volunteers, Commanding.

P. S. -My signal officer is on leave.

W. M.

[Indorsement.]

HEADQUARTERS CAVALRY CORPS,
March 18, 1864.

Respectfully forwarded, for the information of the major-general commanding.

Can a signal officer be sent to General Merritt until his own returns?

C. ROSS SMITH,

Lieutenant-Colonel and Chief of Staff.