Immediately upon receipt of this intelligence, efforts were made to obtain the consent of, or orders from, General Hunter, commanding the department at Fort Leavenworth, Kansas, for the regiment to go to the relief of General Canby, then in command of the department of New Mexico. On the 20th of February, orders came from General Hunter, directing Colonel Slough and the First Regiment of Colorado Volunteers to proceed with all possible despatch to Fort Union, or Santa Fe, New Mexico, and report to General Canby for service. Two days thereafter, the command marched out of Camp Weld two miles up the Platte River, and in due time encamped at Pueblo, on the Arkansas River. At this point further advices were received from Canby, stating that he had encountered the enemy at Valverde, ten miles north of Fort Craig, but, owing to the inefficiency of the newly raised New Mexican volunteers, was compelled to retire. The Texans under Sibley marched on up the Rio Grande, levying tribute upon the inhabitants for their support. The Colorado troops were urged to the greatest possible haste in reaching Fort Union, where they were to unite with such regular troops as could be concentrated at that post, and thus aid in saving the fort and its supplies from falling into Confederate hands. Early on the following morning the order was given to proceed to Union by forced marches, and it is doubtful if the same number of men ever marched a like distance in the same length of time. When the summit of Raton Pass was reached, another courier from Canby met the command, who informed Colonel Slough that the Texans had already captured Albuquerque and Santa Fe with all the troops stationed at those places, together with the supplies stored there, and that they were then marching on Fort Union.