stated repeatedly. On the 25th of October I sent to the General-in-Chief the following telegram:

HEADQUARTERS ARMY OF THE POTOMAC,
October 25, 1862 - 10.45 p. m.

Major-General HALLECK,

General-in-Chief, Washington:

As the moment is at hand for the advance of this army, a question arises for the decision of the General-in-Chief, which, although perhaps impliedly decided by the President in his letter of the 13th, * should be clearly presented by me, as I do not regard it as in my province to determine it. This question is the extent to which the line of the Potomac should be guarded, after the army leaves, in order to cover Maryland and Pennsylvania from invasion by large or small parties of the enemy. It will always be somewhat difficult to guard the immediate line of the river, owing to its great extent and the numerous passages which exist. It has long appeared to me that the best way of covering this line would be by occupying Front Royal, Strasburg, Wardensville, and Moorefield, or the debouches of the several valleys in which they are situated. These points, or suitable places in their vicinity, should be strongly intrenched and permanently held. one great advantage of this arrangement would be the covering the Baltimore and Ohio Railroad, and an essential part of the system would be the construction of the link of railway from Winchester to Strasburg, and the rebuilding of the Manassas Gap Railway Bridge over the Shenandoah. The entrenchment of Manassas Junction would complete the system for the defense of the approaches to Washington and the Upper Potomac. Many months ago I recommended this arrangement - in fact, gave orders for it to be carried into effect. I still regard it as essential under all circumstances.

The views of the chief engineer of this army in regard to the defenses and garrison of Harper's Ferry and its dependencies are in your possession.

The only troops under my command, outside of the organization of the Army of the Potomac, are the Maryland brigade, under General Kenly; the Fifty-fourth Pennsylvania [Colonel Campbell]; Twelfth Illinois Cavalry [Colonel Voss], and Colonel Davis' Eighth New York Cavalry; total 2,894 infantry, one battery, and about 900 cavalrymen. There are also two of my regiments of cavalry (about 750 men) guarding the Baltimore and Ohio Railroad between Hancock and Cumberland. As I have no department, and command simply an active army in the field, my responsibility for the safety of the line of the Potomac and the States north of it must terminate the moment I advance so far beyond that line as to adopt another for my base of operations. The question for the General-in-Chief to decide, and which I regard as beyond my province, is this:

1st. Shall the safety of Harper's Ferry and the line of the Potomac be regarded as assured by the advance of the army south of the Blue Ridge, and the line left to take care of itself?

2d. If it is deemed necessary to hold the line, or that hereinbefore indicated in advance of it, how many troops shall be placed there, at what points (and in what numbers and of what composition at each), and where shall they be supplied, i. e., from this army or from other sources?

Omitting the detached troops mentioned above and the small garrisons of Boonsborough and Frederick, the last returns show the strength of this army for duty to be about 116,000 officers and men. This includes the divisions of Stoneman and Whipple, but does not include Heintzelman, Sige., and Bayard.

If Harper's Ferry and the river above are rendered fully secure, it is possible that the active army, if it supplies the garrison, may be reduced so much as to be inadequate to the purposes contemplated. If it is preserved intact, Maryland, Pennsylvania, and the Baltimore and Ohio Railroad may be unduly exposed.

I leave the decision of these grave questions to the General-in-Chief. I know nothing of the number of troops at Baltimore, & c.

An important element in the solution of this problem is the fact that a great portion of Bragg's army is probably now at liberty to unite itself with Lee's command.

I commence crossing the river at Berlin in the morning, and must ask a prompt decision of the questions proposed herein.

GEO. B. MCCLELLAN,

Major-General, Commanding.

To which I received the following reply:

WASHINGTON, October 26, 1862 - 1.35 p. m.

Major General GEORGE B. MCCLELLAN:

In addition to the command which you had when I came here, you also have the greater part of that of Major-General Pope. Moreover, you have been authorized to

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*See Addenda to Halleck's report, p. 13.