Numbers 209.

Report of Colonel Oscar F. Harmon, One hundred and twenty-fifth Illinois Infantry.

HEADQUARTERS 125TH ILLINOIS VOLUNTEERS, In the Field, near Chattanooga, September 24, 1863.

SIR: In pursuance of orders, I have the honor to report the part taken by my command in the battle of Chickamauga, September 19 and 20.

At 3 p.m., September 18, I was ordered to march from Rossville in the rear of the Eighty-sixth Illinois Volunteer Infantry by the left flank. A rapid march of two hours brought the brigade of which my regiment is a part within a half mile of Reed's Bridge, across Chickamauga River. It being then dark, the brigade took position upon a low hill gently descending to the north and east. Two lines were formed, of which my command formed the right of the second. The men slept upon their arms without fires, the night being intensely cold.

Standling to arms at 3 a.m., at early dawn two new positions were taken without relative changes in the brigade.

A spring had enticed several of the men to the front for water; they, being discovered by the enemy, were fired upon, but no one was injured; 1 man losing his gun in the hasty retreat. The enemy advanced rapidly, engaging and driving our skirmishers, the bullets from the enemy's guns passing over our heads.

At this moment, 8 o'clock, I noticed Barnett's battery and the Eighty-sixth Illinois Volunteer Infantry falling back on the double-quick to my right. Having no orders, I remained until Lieutenant Rogers, aide to Colonel McCook, informed me the brigade was ordered to retreat, when I fell back by the right flank in the rear of the Fifty-second Ohio Volunteer Infantry, the march being continued until the brigade reached the crest of Missionary Ridge to the left of the Rossville road.

A double line was here formed, I being placed upon the left of the second line and in double column. By sunrise the brigade was again marching down the road leading to the front and enemy's right, my regiment in the rear.

At 10 a.m., having advanced several miles and the scouts having reported the enemy near, the brigade filed back a half mile, and occupied a hill cleared and owned by Mr. Green. My regiment was posted upon the right of first line, supporting Barnett's battery. Here General Granger joined us and made extended observations, but no enemy appeared.

At 12 m. was ordered to march by the right flank with flankers to my left, the brigade not changing in the march its order in line. Coming up to General Steedman's command, an opening was occupied on slightly elevated ground; my command held the left of the first line. No enemy appeared. The brigade remained at this place until about 2,30 p.m., when it again moved toward General Thomas' left by the right flank, One hundred and twenty-fifth in rear.

In approaching the enemy's right their skirmishers appeared and fired upon us, when the brigade moved on double-quick to a strong position on the crest of a high hill, facing the enemy in two lines, I being upon the left and rear. A heavy fire was opened upon us from two batteries, which was vigorously answered by Barnett's battery.