their inspectors-general or personally, keep themselves minutely acquainted with the condition of their troops.

Special evidence will be forwarded within twenty-four hours after this order is received at the various division headquarters that it has been published to every regiment, battery, and detached company of the commands receiving it.

By command of Major-General McClellan:

S. WILLIAMS,

Assistant Adjutant-General.

FAIRFAX COURT-HOUSE, October 24, 1862.

Major-General BANKS:

The enemy begins to show great activity against our lines, our pickets having been driven in from Manassas Junction this p. m. An arrangement should, therefore, be made to counteract their movements. I must know on what cavalry force I can rely. Please give the report of General Stahel your earnest consideration, and inform me, by telegraph, of your decision immediately.

F. SIGEL,

Major-General.

[Inclosure.]

I beg leave to call your attention to the following facts in regard to our cavalry force:

Colonel Wyndham, who should have reported with 1,000 men, brought out but 875, with but one field officer. Since then many of the men ran back, without leave, to their old camps, and others were sent back on account of having unserviceable horses, so that the whole force of Colonel Wyndham is now 593 effective men. From this force, 492 are stationed at Chantilly. From this force in Chantilly, 140 men are on picket and patrol duty. The command of Colonel Wyndham has been under orders for a long and rapid march, so that I could make no detail from it. The cavalry force in Centreville consists of 100 men from Colonel Wyndham's command and our old cavalry force, of which the Ninth New York Regiment is under orders from General Bayard to remain in camp, and to have no details from it, so that all my disposable cavalry force are, in accordance with your orders, on picket and patrol duty. This evening I found myself compelled to order Colonel Wyndham, with 130 of his men, to go toward Gainesville to cover the force sent out to Gainesville, Hay Market, and Thoroughfare Gap. From this report you will see how restricted I am in regard to cavalry force. I am left without a man, and, as the rebel cavalry are moving around my force in superior numbers, I consider it necessary that all the cavalry here be placed at my disposal; that the order of General Bayard in regard to the Ninth New York Cavalry and Colonel Wyndham's command be suspended, and that the latter be filled up to 1,000 effective men, inasmuch as I have such an extensive line to cover and so few men to do it with, it being absolutely necessary to send out strong forces to do the reconnaissance service and guard against surprises.

JUL. STAHEL,

Brigadier-General.

(Repeated by Banks to McClellan, October 25.)