September 21, early in the morning, my division was disposed so as to hold the gap and mountain crest east of Rossville.
2 p. m. the enemy advanced a heavy force, with artillery, on the La Fayette road, and on the crest of the mountain.
After a brisk engagement, with artillery and musketry, he was checked in the gap by Stanley's brigade and driven from the mountain crest by a gallant charge of the Fifteenth Kentucky, General Beatty's brigade.
5 p. m. the enemy was seen moving in heavy columns to our right, and massing a considerable force in our front.
He was able to shell our position, which was greatly exposed to his artillery and which would become immediately untenable should he plant artillery on the crest of the mountain beyond our line; at the same time communication with Chattanooga could be easily cut off.
The troops were without supplies and the animals had had no food for twenty-four hours. The troops were accordingly ordered to fall back to Chattanooga.
6 p. m. the Sixty-ninth Ohio Volunteers, of Stanley's brigade, which had been left at Cowan, arrived and took position in the gap. My division was directed to quietly withdraw to Chattanooga at midnight, leaving three regiments to hold the picket line until daylight. This important duty was intrusted to Colonel Stoughton, Eleventh Michigan Volunteers, who performed it in a most judicious manner. My command reached Chattanooga at 2.30 a. m., and took the position designated by Major Bond, of General Rosecrans' staff.
At daylight we occupied the unfinished rebel fort on the west side of Chattanooga and La Fayette road, and immediately commenced its completion for defense.
I beg leave to refer to the reports of General Beatty and Colonel Stanley for the details of the brilliant operations of their brigades while temporarily separated by order, and the tide of battle on Sunday. The conduct of these two officers was highly creditable, and that of their troops brave and efficient.
General Beatty gallantly remained upon the field of battle, in command of scattered troops, after most of his brigade had been driven from it and separated from him by the charge of the enemy upon his left.
Colonel Stanley continued to command his brigade until he received a severe contusion from a fragment of a shell, when Colonel Stoughton, Eleventh Michigan Volunteers, assumed command and ably handled the brigade.
In Sirwell's brigade, the Twenty-first Ohio Volunteers, which assisted General Brannan, suffered severely, holding their position at the base of the ridge until they had exhausted nearly all their ammunition and were compelled to supply themselves from their dead comrades.
When General Brannan retired with his division, the remaining portion of the Twenty-first Ohio Volunteers was left to hold their position, during which time they lost heavily.
The balance of Colonel Sirwell's brigade, although deployed at several points, and compelled to change position frequently during the day, rendered valuable services not only in battle but, with the assistance of the Ninth Michigan Volunteers, in rallying and organizing a number of the scattered troops, and in saving the artillery and transportation, which occupied the road and chocked up the gap, endangering the immediate capture of the whole by the enemy.