different classes at work in the gold region, made it highly important that a strong military force should be established in the immediate vicinity of the mining region. For the disposition of the troops in the department, and the measures taken to prevent desertions, &c., I respectfully refer to department order and special orders forwarded to you by this mail. These furnish you with a history of the operations in the department since my assumption of the command. The present disposition of the troops is the same as indicated in orders No. 16, except that company A, 2d infantry, re-inforced by details from other companies--in all, four officers and eighty men--has been detached, under instructions from the commander of the division, as an escort for Captain Warner, topographical engineers, and company E, 1st dragoons, when _en route_ for the station, was diverted from that route, for the purpose of securing the perpetrators of some murders committed by Indians on or near Los Reyes River. The difficulties apprehended from a collision between the different classes of the mining population have not yet occurred in the form which it was feared they would assume, and at present I do not apprehend any serious difficulty from that source. Some serious Indian disturbances have occurred on the American fork of the Sacramento, and a few isolated murders have occurred at other points; but at the date of the last report from the frontier, every thing was quiet. The Indians of the Sierra Nevada, although in a great number, are of a degraded class, and are divided into so many different tribes, or rancherias, speaking different languages, that any combination on their part is scarcely to be apprehended. Their depredations heretofore have been confined generally to horse-stealing, and only occasionally have murders been committed by them. These, however, have been made the pretence, by the whites in their neighborhood, for the commission of outrages of the most aggravated character--in one or two cases involving in an indiscriminate massacre the wild Indians of the Sierra and the tame Indians of the ranchos. The commanders of detachments serving on the Indian frontiers are instructed to prevent any authorized interference with the Indians by the whites, and to support the Indian agents of their districts in the exercise of their appropriate duties. From the character of the mining population, and the nature of their occupations, unless a strong military force be maintained on that frontier, it will be impossible to prevent the commission of outrages upon the Indians; and they, in turn, will be avenged by murders committed upon isolated parties of whites. Unfortunately, the eagerness with which gold is sought after by detached parties of miners, gives many opportunities for the commission of such outrages. To seek after and apprehend the perpetrators in cases of this kind, a mounted force is absolutely