On the afternoon of the 15th instant Rev. Mr. Riggs, chaplain of the expedition, learned from a friendly Indian among my scouts that a party of Sioux were encamped on the other side of Lac-qui-Parle, about 15 miles distant, and communicated the fact to me, suggesting the possibility of their capture. I immediately organized an expedition, under the command of Captain Merriman, of B Company, of the Sixth Infantry, consisting of his own company, 15 mounted men, under Sergeant Fox, of the Third Infantry, and 10 mounted scouts attached to these headquarters, under Lieutenant G. A. McLeod, and ordered a movement to be made at 10 o'clock in the evening. The instructions given by me to Captain Merriman were strictly executed, and resulted in the capture, without even a show of resistance, of 22 men, 22 women, and 23 children, most of the latter being known as deeply implicated in the late outrages. These were conducted under escort to these headquarters and properly secured, while the women and children were ordered to join the general camp at Yellow Medicine, whither they have gone under guard this morning. I beg leave to add that the whole affair was a complete success, and that I issued an order yesterday, which was read at dress parade, expressing my appreciation of the good conduct of all the officers and men employed in the expedition.

Nothing further has been heard from the detachment under Lieutenant-Colonel Marshall, which left here at midnight of the 13th instant. I shall expect him to return within three days. The second detachment of cavalry dispatched by you has not yet arrived.

The military commission is engaged in trial of the prisoners, having been convened yesterday. The cases of some 20 men have been disposed of, but not yet submitted to these headquarters.

I have now 123 Indian men prisoners, including the 20 first sentenced, and 236 men are confined at Yellow Medicine, 20 miles below this point.

As the Indians reported their forces at Yellow Medicine to be about 750 (exclusive of halt-breeds, who were forced to be present), about one-third of whom did not participate in the conflict there, or rather at Wood Lake, my estimate is as follows, based on the best information I can obtain, to wit:

Entire force of the Medawakanton, Sioux, and Wahpetons.... 750

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Prisoners in Camp Release................................. 123

Friendly Indians (scouts) in-same camp.................... 5

Prisoners at yellow Medicine, strictly confined........... 236

Friendly Indians there, under surveillance................ 63

Killed in engagement at Wood Lake (know at least)......... 30

Wounded (supposed)........................................ 40

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497

Say 500 warriors accounted for, leaving 250, besides the 100 in White Lodge and Sleepy Eyes' bands of Sioux Sissetons, who committed the Lake Shetek massacres, yet to be found and dealt with. I believe the above to be nearly correct. If there is any error, it will be found to be in overrating the men still at large. The estimate embraces all the bands below Big Stone Lake. I am convinced I am not far wrong when I state the Sioux Indians above as follows:

Sissetons of Standing Buffalo, Wanatua, and Red Feather, with other smaller bands at Big Stone Lake and Lake Traverse.............. 450

Eastern Yanktonnais, including Cut-Heads and Ouk patiens [Uncapapa?]................................................... 800

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1,250