FORT KEARNY, August 16, 1864.

Major-General CURTIS,

Omaha:

Your dispatch is received. The amount of damage done west of here is hard to estimate. There have been twenty persons killed between here and Cottonwood and one train burnt. The ranchmen have all left, except where we have posts from Cottonwood and Julesburg. The ranchmen have all run except two posts occupied by the military. The stage stock has been taken off to-day, I am informed by the agent, from Julesburg to Cottonwood. Unless the Government intends to abandon the Laramie route entirely, I have taken all the troops off that route that can possibly be spared. I have taken from that route two companies of the Eleventh Ohio, one stationed at Fremont's Orchard, the other at Camp Collins, extending two posts toward Julesburg. I have made the headquarters of one company Seventh Iowa Cavalry at Julesburg, one post extending each way. We occupy the road west from Collins to South Pass. My troops are just scattered enough to be cut up by detail. Captain Murphy, Seventh Iowa Cavalry, has been on the Blue since last Thursday with his company. Have heard nothing from him since he left Pawnee Ranch. Major O'Brien reports a skirmish between his troops and Cheyennes to-day at 12 m. six miles east of Cottonwood. I will probably start for Omaha to-morrow for the purpose of conferring with you.

ROBT. B. MITCHELL,

Brigadier-General, Commanding.

HEADQUARTERS DISTRICT OF NEBRASKA, Omaha, Nebr. Ter., August 16, 1864.

Honorable ALVIN SAUNDERS,
Governor of Nebraska Territory:

GOVERNOR: I have the honor to communicate the following extract form telegraphic dispatch of this date from Brigadier-General Mitchell, at Fort Kearny: "If troops are not in the field this road will go back to the aborigines." In accordance with General Mitchell's directions, I have the honor to inform you that every effort will be made by the military authorities here to aid you in arming, subsisting, &c., of the militia, to aid in the emergency caused by the presence of the large force of hostile Indians the Platte Valley. Your Excellency is probably aware that the number of effective troops in the district has been but barely sufficient to garrison the several posts, even while there has been no concerted action by large bodies of hostile Indians, and the speedy addition of all the forces that can be put into the field (it will be seen by General Mitchell's dispatch) is necessary to prevent incursions and outrage on the line, if not to save even the garrison of the posts now held by our troops.

JNO. PRATT,

Assistant Adjutant-General.

EXECUTIVE DEPARTMENT, COLORADO TERRITORY, Denver, August 16, 1864.

Colonel J. M. CHIVINGTON,

Commanding District of Colorado:

SIR: I have the honor herewith to inclose for your information copies of letters received from Major Colley and Mr. Bent in reference to the hostile disposition of the Indians in the vicinity of Fort Lyon.

D. A. CHEVER,

Private Secretary.