Arriving at Red River about sundown, the regiment was drawn up in line and this information imparted to the men. The request was then made for all who were willing to undertake a forced march at night to step two paces to the front, when every man advanced to the new alignment. After a hasty supper the march was resumed, and at sunrise the next morning they reached Maxwell's Ranch on the Cimarron, having made sixty-four miles in less than twenty-four hours. At ten o'clock on the second night thereafter, the command entered Fort Union. It was there discovered that Colonel Paul, in charge of the post, had mined the fort, giving orders for the removal of the women and children, and was preparing to blow up all the supplies and march to Fort Garland or some other post to the northward, on the first approach of the Confederates. The troops remained at Union from the 13th to the 22d of March, when by order of Colonel Slough they proceeded in the direction of Santa Fe. The command consisted of the First Colorado Volunteers; two Light Batteries, one commanded by Captain Ritter and the other by Captain Claflin; Ford's Company of Colorado Volunteers unattached; two companies of the Fifth Regular Infantry; and two companies of the Seventh United States Cavalry. The force encamped at Bernal Springs, where Colonel Slough determined to organize a detachment to enter Santa Fe by night with the view of surprising the enemy, spiking his guns, and after doing what other damage could be accomplished without bringing on a general action, falling back on the main body. The detachment chosen comprised sixty men each from Companies A, D, and E of the Colorado regiment, with Company F of the same mounted, and thirty-seven men each from the companies of Captains Ford and Howland, and of the Seventh Cavalry, the whole commanded by Major Chivington.