vance on Winchester. Have sent squadron of cavalry, section of artillery, and Rhode Island regiment towards Cumberland to sustain Colonel Wallace, threatened by a large force and demanding aid, and who may be forced to Hancock. Sustain this by another regiment. Wish to retain regulars for the present, if the General-in-Chief is not urgent. I write by Colonel Sherman to-night.

R. PATTERSON,

Major-General, Commanding.

HAGERSTOWN, MD., June 16, 1861.

Colonel E. D. TOWNSEND, Asst. Adjt. General, Hdqrs. of the Army:

COLONEL: I have the honor to report, for the information of the General-in-Chief, my arrival last evening in this place.

From time to time I have notified you of the condition of the command to move, and my intention soon to advance to this place with a force which could maintain any position it might take. With our own transportation, aided by every wagon and team which could be hired contiguous to our camps, in Pennsylvania and in this place, I advanced yesterday (the earliest moment) General Cadwalader's division, and sent the largest portion of General Keim's by rail. The remainder, with the supplies, are now rapidly coming in. General Cadwalader encamped last evening near Williamsport; to-day, under my instructions, he will cross the river and occupy the bend to Falling Waters, and will be prepared to push on to Martinsburg, to which place he sends an exploring force. He will be sustained by Generals Wynkoop and Negley, whose brigades are posted for the purpose.

Early yesterday morning I received simultaneously reliable information of the evacuation of Harper's Ferry, and a threatened attack upon Colonel Wallace at Cumberland, with a call for aid, which General Morris, in rear, had refused. I directed Colonel Wallace to hire transportation, maintain a bold front to the last moment, and, if hard pressed, to move towards Hancock, in which direction horse, foot, and artillery would be sent, with orders to push on to him; or, at his discretion, to fall back upon Bedford, communicating the fact to the column on this side. With the spirit of a true soldier he has prudently determined to stand, and retire contesting the ground, unless he will have to sacrifice his men.

Confident the enemy had retired and was in rapid retreat from Harper's Ferry, I ordered a force to be detached to Cumberland. Owing, as will be seen by the accompanying letters, to the want of the means of transportation and the fagged condition of the command, the march being long and the day oppressively hot, the command could not be put in motion.

Major Porter late at midnight visited General Cadwalader at Williamsport, and arranged to send to-day a section of artillery, a squadron of cavalry, and the Rhode Island regiment, Colonel Burnside-a gallant soldier and a gallant command-to support the noble Indiana regiment, similarly commanded. The transportation for that command exhausted all available wagons and checked, had I been able and it been prudent, further advance to push on a fleeing enemy. On the approach, suddenly on their rear of this well organized force, and the steadily advancing column under Colonel Stone, the enemy appear to have hastily decided to evacuate the position they had openly declared should be held at all hazards. They have fled, and in confusion. Their retreat is as