of the enemy. It might be well to send citizens, if you can get them to go, and send any information you may get to these headquarters by telegraph from Hagerstown or Frederick, as may be most convenient.

You will take the best route to cut off the enemy, depending on the information you obtain. Pursue them vigorously, and do not spare you men nor horses, if you see an opportunity of overtaking them. They should not be allowed to escape unharmed.

R. B. MARCY,

Chief of Staff.

HEADQUARTERS ARMY OF THE POTOMAC,
October 11, 1862-3.30 p. m.

Major General FITZ JOHN PORTER,

Commanding Fifth Corps:

GENERAL: The commanding general desires that you will exercise special vigilance in watching the fords and all possible crossing places on the river picketed by your command, to prevent all possibility of the enemy crossing a force to this side, to make a

diversion in aid of the escape of their cavalry, now here, or, in case this latter force should merely be a feint, to draw attention, and enable them to cross their army again without serious opposition. In view of these possibilities, however remote, you will please take every step in your power to prevent such a movement on the part of the enemy.

Yours, very respectfully,

R. B. MARCY,

Chief of Staff.

By WM. F. BIDDLE,

Captain and Aide-de-Camp.

COLLEGE OF SAINT JAMES,

October 11, 1862-6 p. m.

Brigadier General S. WILLIAMS,

Asst. Adjt. General, Headquarters Army of the Potomac:

GENERAL: I have received the following, partly official and partly

rumor, from Hagerstown, brought by officers just arriving at their

camp here:

General Stuart crossed at McCoy's Ferry yesterday morning with about (said to be) 3,000 men and one battery. Arrived at Mercersburg and took mail and postage-stamps from office, giving for the latter receipt and promise to pay. General Stuart is stated to have said that he was ordered over, but never expected to get back?

Confederates had arrived at Chambersburg, and were rifling the warehouses. Railroad communication broken between Hagerstown and Harrisburg.

General Pleasonton had gone from Hagerstown with cavalry and infantry (Hancock's brigade). General Averell must have known yesterday of the crossing of the enemy, and must be on their track by this time?

Smith's division passed up toward Hagerstown to-day.

I have put a query to such as I give as reports. All quiet on my lines. If General Stuart was ordered over, was it to check movement on our side, or cover one on theirs, and would he have stated as above?

I am, general, very respectfully, your obedient servant,

F. J. PORTER,

Major-General.

P. S.-Did they not know of clothing being essential for us, and this raid would cause delay in its arrival at Hagerstown?

F. J. P.