HEADQUARTERS DEPARTMENT OF THE PACIFIC,
San Francisco, April 20, 1863.

Brigadier General L. THOMAS,

Adjutant-General U. S. Army, Washington, D. C.:

GENERAL: I have received Major-General Halleck's dispatch of the 15th instant. I had previously called upon the acting Governor of Nevada Territory for troops to operate on the Overland Mail Route, in the direction of Salt Lake, and from his reply I think we can raise in that Territory 200 mounted men, and possibly two companies of infantry. I have urged upon the Governor the necessity of promptly enrolling the companies. Although the line is comparatively quiet just now, yet it is liable to interruption at any moment by predatory bands of Indians. The two companies of the Third Infantry California Volunteers, now at Camp Union, Sacramento, will be put on the march for Utah as soon as practicable; at this moment it is impossible to forage our animals east of Carson City. The cavalry company stationed at Fort Churchill was under orders to move along the mail line, but I was compelled to send it first to aid in quelling the Indian disturbances in Owen's River Valley; when this is accomplished the company will be advanced promptly toward Salt Lake. We have had many affairs with the Indians lately in the Dsitrict of Humboldt, in the Owen's River Valley, on the overland mail line, and south of Camp Douglas, in all of which our troops have been victorious; a large number of Indians have been killed and their property, with their women and children, captured. The California troopsb have behaved most gallantly, and deserve the highest credit. General Alvord has commenced his movement toward Fort Boise, on Snake River, to establish a post at that place in accordance with the instructions from the War Department.

Lieutenant-Colonel Drew, with two companies of Oregon cavalry, is making preparations to move from his camp, near Jacksonville, east to the neighborhood of the Klamath Lakes, to establish a post in that vicinity for the protection of the emigrant route. A few weeks since the public mind on this coast was roused to the highest pitch; apprehensions were entertained that the sympathizers with rebellion were secretly organizing and preparing to raise the rebel falg in our midst. I am satisfied that these apprehensions were no tgroundless, although much xaggerated. I have been prepared to meet any emergency, keeping my troops well in hand and myself well posted as to the state of affairs in the most disaffected districts. This alarm, lest this State should be thrown into the vortex of civil war, has been productive of the greatest good. It has aroused the whole of the loyal population of the State to a sense of their duty and to be prepared to crush out any attempt to disturb the peace of the State. Great mass meetings of loyal and true men are being held in every city, town, and county in the State. Great Union leagues are everywhere forming, composed of men sworn to uphold the Government and maintain the Union. This is real strength. The Governor of the State and all of the high officers and leading citizens are united as one man to promote the organization of these leagues. As commander of this department I have most cordially approved and aided this union of the loyal element. This upheaving of the patriotic masses of California will have a happy effect in quieting the apprehensions of the people, as well as in striking terror into the hearts of the traitors.

With great respect, your most boedient servant,

G. WRIGHT,

Brigadier-General, U. S. Army, Commanding.