Skirmish near Fort Thorn, New Mexico Territory

First Lieutenant Corydon E. Cooley of the Second New Mexico Volunteer Infantry Regiment (who acted as Morris' aide de camp), riding in advance, discovered the Texan's encampment at E Company Grove, 80 mi (130 km) from Fort Craig. Morris formed his command for a charge, but after examining their position, found them strongly posted and protected by a barricade of fallen timber, and saw it was futile to attempt a charge at that time. To test their strength Morris ordered Lieutenant Treacy, with Company C, to take position on their right flank and attack them, while Morris himself moved forward to attack them on their front and left.^{[2]: 29–30}

Meanwhile, at his breakfast, Captain Coopwood was informed that his pickets were running into camp, and, rising to his feet, saw Morris's men pursuing them. In less than ten minutes the Confederate camp was surrounded by U. S. troops, that Coopwood believed numbered about 190 men.^{[2]: 31–32}

Captain Morris wrote:

Taking up my position, a single shot was fired. I immediately dismounted and went into action, which lasted an hour and forty-two minutes.^{[2]: 29–30}

Coopwood wrote that:

...firing commenced at 7 o'clock and ended at 11 a. m.

The principal portion of the battle was fought with the enemy's force formed in two lines, forming the angle of a square, and my forces formed the same way inside of theirs, my lines being much the shorter. One of my lines was composed of the detachment from Captain Pyron's company and a portion of the detachment from Captain Stafford's company, under the immediate command of Lieutenant Poore, Sergeant O'Grady, and Sergeant Browne. My left line was composed of the detachment from my company and a part of the detachment from Captain Stafford's company. This line was under the immediate command of Lieutenant Sutherland, being divided into two platoons, one led by Sergeant Coulter, and the other by Private Tevis, who was named for the special occasion.

The enemy began to retreat before 11, and about that hour fled from the field.^{[2]: 31–32}

Morris wrote about his withdrawal:

My ammunition running low, I retired a half mile as a feint to draw them out from their entrenchments, but without success. I then turned their right and camped 2 1/2 miles from them, where I remained till 5 p. m.; then I moved up the creek and encamped, where I remained until dark, and then moved back on Canada Alamosa with my wounded, which place I reached at 4 a. m. on the 27th instant.^{[2]: 29–30}

Coopwood wrote that:

I remained upon the field till 10 o'clock a. m. the next day, but was prepared to receive another attack should the enemy return re-enforced." I lost 2 men killed, and had 2 severely wounded, each in the arm, besides 6 others slightly wounded,..... The enemy removed their dead and wounded as they retreated, so as to evade a discovery of their losses; but, from the number of horses led away with bodies apparently lashed across them, there were 12 or 13 killed, but the number of their wounded could not be ascertained.^{[2]: 31–32}

Captain Morris did not put the number of his casualties in his report, but that of his superior, Col. E. R. S. Canby reported that both sides had roughly equal numbers engaged and both the Confederate loss and that of Morris. "Their captain, 10 men, and 22 horses were killed, 30 men and a large number of horses wounded. In Captain Morris' command 3 men were wounded."^[2]: 26 This roughly quadrupled the actual Confederate loss of men and wrongly asserted Captain Coopwood was killed. Captain Coopwood himself overestimated the number of Union troops he engaged and had also overestimated the loss to the Union troops in a similar manner.

• New Mexico campaign

33°04′05″N 107°17′06″W / 33.068°N 107.285°W / 33.068; -107.285