infornia Volunteers, under the command of Lieutenant Colonel J. R. West, to relieve the regulars stationed at Fort Yuma. Regular troops stationed at different parts of the State were ordered to rendezvous at two points, viz, San Diego and San Pedro, for the purpose of embarkation, orders having been issued by the War Department that all regular troops on the Pacific coast be sent to the seat of war in the East. Brigadier General E. V. Sumner, at that time in command of the Department of the Pacific, was also ordered in. On the departure of General Sumner, Colonel George Wright, Ninth U. S. Infantry, assumed command of the department. The Southern District of California was turned over by Colonel Wright to the command of Colonel Carleton.

During the two succeeding months quiet and order were restored throughout the southern part of the State. The distribution of the troops indicated to the disaffected the determination of the authorities to keep California firm and steadfast to the Union.

On the 12th of January Colonel Carleton was summoned to San Francisco, to consult with Colonel Wright in reference to the movement of troops into Utah. About this time rumors reached California that Van Dorn, of the rebel service, was fitting out an expedition for the invasion of California by way of Arizona. The fact was well-established that Arizona and a portion of New Mexico were occupied by Confederate troops, and it was apparent to all that California was more accessible through Arizona by way of Fort Yuma than any other point.

Fort Yuma, located on the Colorado River, on the southeastern line of the State, is our extreme outpost. Surrounded as it is by a vas desert, if once in the possession of an enemy the key to the State was lost.

In view of all these threatened dangers to the State and coast General Wright suggested to the War Department that perhaps the Government would be better served by throwing the California troops into Arizona and driving the rebels from that Territory. A double object would thus be gained; first, an effectual guard would be kept against any invasion of the Pacific coast from that quarter; second, the California troops would fall in the rear of the Confederate forces then in New Mexico and assist the Federal forces in expelling them from that Territory.

The suggestions of General Wright were favorably received by the War Department. The feasibility of the movement was so apparent, that the consent of that Department was at once obtained.

On the receipt of the decision of the War Department authority was granted to Colonel Carleton to organize and fit out the expedition.

The Fifth Infantry, California Volunteers, under the command of Colonel George W. Bowie; also Company A, Third U. S. Artillery, with a light battery, under command of First Lieutenant John B. Shinn, of the U. S. Army, were added to Colonel Carleton's command; also Captain Cremony's company, Second Cavalry, California Volunteers.

Active preparations were at once made for the movement of the column. It was important that the troops should move as soon as possible, in order that they might receive the benefit of the cool winter weather while passing over the Gila and Colorado Deserts. The great distance from the Pacific Ocean to the Rio Grande, the entire and complete desolation of nearly the whole route, presented obstacles almost insurmountable to marching a column of over 2,000 men and the same number of animals. It was well known that forage and provisions could be obtained but at two points between Fort Yuma and the Rio Grande in time of peace, and then in limited quantities, viz, at the Pima Villages and at Tucson; and it being known that the