MAY 9-10, 1864.-Scout from American Ranch to Cedar Bluffs, Colo.

Report of Major Jacob Dowing, First Colorado Cavalry.

AMERICAN RANCH, May 11, 1864.

COLONEL: My scouts having reported on the 9th instant that a body of Cheyennes had again taken possession of the canon at Cedar Bluffs, where a few days since I reported to you that i had skirmished with them, and that several war parties had seen in the vicinity of the Platte, and in one instance having attacked a ranch and were driven off, I immediately prepared a command to go again to the canon, feeling that in that manner only could I drive them from the river and remove the danger. Therefore, on the 9th instant, at 2 p. m. with about 80 men. I marched 20 miles down Platte to Moore & Chesby's ranch when, after halting toll 6 p. m. of the same day, started for the canon, about 40 miles distant, and reached it about daylight in the morning; but the Indians, determined not to be surprised this time, decamped, leaving all their lodges, fourteen in number, cooking utensils, about 130 saddles, and in fact everything belonging to them, not even excepting their dried meats, &c., all of which I destroyed. Shortly afterward I discovered a large encamped of Sioux Indians, who informed me that they were desirous of place, and that the Cheyennes, having abandoned everything, the believed before the y stopped for any time would go to Powder River; that they (the Cheyennes) had applied to the Sioux for assistance to fight the soldiers, and that they (the Sioux) had refused to join them, when the Cheyennes in their fright determined to seek safety in flight. The Sioux thought that a war party of the Cheyennes, about 25 in number, had gone to the Platte to steal horses in order to make their escape more certain.

In order to stop their depredations on the river, after halting two hours, I determined to reach the river as soon as possible, when, after a rapid march, reached the Platte about 8 p. m. on the evening of the 10th instant, where I learned that Indians had been seen during the afternoon, and that the settlers apprehended trouble. I immediately ordered out patrols, and to the present time everything is quiet as far I have been to learn. I can no estimate of the time it will take to entirely subdue these deprecators, but think that everything thus far is favorable to a speedy adjustment of this difficulty, provided the pursuit is, for a short time hence, vigorously maintained.

I intend ordering Lieutenant Chase with his detachment to report for duty to Camp Sanborn, and Lieutenant Murrell with his detachment to the Junction station, 34 miles up the river, when I think the road to Denver from this will be comparatively safe. I intend starting to-morrow morning for Danver to talk you regarding this affair, if it meets you approval. If you should not approve my coming, telegraph me at the Junction.

Hoping, sir, that what I have done will wee your approval, I remain, most respectfully, your obedient servant,

J. DOWING,

Major, First Colorado Cavalry.

Colonel J. M. CHIVINGTON,

First Colorado Cavalry, Commanding District.