In accordance with instructions, the command left camp opposite Bridgeport, Ala., at 7 o'clock on the morning of the 13th instant, for Chattanooga, taking with them only blankets and five days' rations.

At 9 o'clock the next morning Chattanooga was passed on our left, and at 11 o'clock we bivouacked at Rossville, Ga., having marched a distance of nearly 40 miles in thirty consecutive hours.

On the morning of the 17th instant, the brigade formed a part of the force which marched to Ringgold, 16 miles from Rossville, drove in the enemy's pickets, and planted a battery on the crest of a hill commanding the town.

On the morning of the 18th instant, the command returned to Rossville, and in the evening of the same day was ordered to the support of Colonel D. McCook, commanding the Second Brigade, Second Division, Reserve Corps, who had taken a position between the Ringgold and the La Fayette roads.

On the morning of the 19th instant, our skirmishers engaged the enemy's advance, and the engagement was fast becoming general when a peremptory order recalled us to Rossville, to place three days' rations in haversack, and proceed to the support of Brigadier-General Whitaker, whose command was lying on the Ringgold road, 4 1/2 miles southeast of Rossville. Here the command rested on their arms during the night of the 19th.

At 11 o'clock on the morning of the 20th, we were ordered across to the La Fayette road, thence to the proximity of the Fourteenth Army Corps. During the last mile of this march, our left flank was constantly threatened by the enemy's cavalry, and our column endangered by the continued firing from masked batteries. After having reached the extreme right of the center, Fourteenth Corps, we found the country one series of ridges separated from each other only by a few hundred yards of thick woods.

At 11 o'clock on the morning of the 20th, we were ordered across to the La Fayette road, thence to the proximity of the Fourteenth Army Corps. During the last mile of this march, our left flank was constantly threatened by the enemy's cavalry, and our column endangered by the continued firing from masked batteries. After having reached the extreme right of the center, Fourteenth Corps, we found the country one series of ridges separated from each other only by a few hundred yards of thick woods.

At 1 o'clock an order was received to form line of battle, which was arranged as follows: One hundred and Twenty-first Ohio, Lieutenant Colonel H. B. Banning commanding, on the right; the Ninety-eighth Ohio, Captain M. J. Urquhart, on the left, with the Seventy-eighth Illinois, Lieutenant Colonel Carter Van Vleck, and the One hundred and thirteenth Ohio, Lieutenant Colonel D. B. Warner, in the center. Battery M, First Illinois Artillery, Lieutenant Thomas Burton commanding, took position on the extreme right, supported by two companies of the One hundred and thirteenth and One hundred and twenty-first Ohio Regiments.

When the line, thus formed, reached a point half way up the last of the mentioned ridges, the enemy appeared in force on the crest, and opened a murderous fire.

The order to charge was given, and in response the solid line rushed to the crest, drove the enemy from his position, and held it.

Three several times the enemy rushed upon us to hurl back our line, but in each instance he was met, and gallantly repulsed. In one of these charges, when the conflict had become hand-to-hand, the One hundred and twenty-first Ohio captured the flag of the Twenty-second Alabama Regiment, and bore it with them from the field.

For five hours the command remained in the position first gained, holding it against the repeated assaults of greatly superior numbers, and at sundown, after the last cartridge was fired, fell back to the ridge first in our rear.