lines appear as yet to be undisturbed. The enemy have cut the canal to let out water. Reliable persons say the Potomac can be forded at almost every point. My troops are all new, and unacquainted with the duties required of them. It is especially so with the officers. I am doing all that I can to improve them. It was reported to Mr. Garrett, president of the railroad, that about 5,000 men passed during the night at the mouth of the Monocacy River. they fired on pickets with infantry and artillery. I have two regiments here, arming themselves, but the officers and men are wholly ignorant of their duties. They will be of no use in the field. I propose to place them at Washington Junction and Relay House. Telegram just received from Colonel Cram, dated Monocacy, 12 m., says he has reason to believe that 30,000 rebels crossed at the mouth of the Monocacy River last night. Two brigades of rebels are reported to be at Charlestown, 8 miles from Harper's Ferry. Another dispatch to Mr. Garrett says the enemy has crossed the river, at or near the mouth of the Monocacy, 30,000 strong, and more to come, under command of General Hill. Answer.

JOHN E. WOOL,

Major-General.

WAR DEPARTMENT,

Washington, September 5, 1862.

Major-General WOOL, Baltimore, Md.:

I find it impossible to get this army into the field again in large force for a day or two. In the mean time Harper's Ferry may be attacked and overwhelmed. I leave all dispositions there to your experience and local knowledge. I beg leave, however, to suggest the propriety of withdrawing all out forces in that vicinity to Maryland Heights. I have no personal knowledge of the ground, and merely make the suggestion to you.

H. W. HALLECK,

General-in-Chief.

HEADQUARTERS OF THE ARMY,
Washington, September 6, 1862.

Major-General McCLELLAN,

Commanding, &c.:

GENERAL: You need not wait for the change of commanders, but move McDowell's corps at once. I think the charge will be made this afternoon. I will try immediately.

Yours, &c.,

H. W. HALLECK,

General-in-Chief.

P. S. - Hooker has been assigned to Porter's corps, and it has been directed that Reno be assigned to McDowell's.

H. W. H.

HEADQUARTERS ARMY OF THE POTOMAC,
September 6, 1862.

Major-General HALLECK:

GENERAL: General Sumner reports the enemy moving toward Rockville. It will save a great deal of trouble and invaluable time if you