No. 63. report of Col. P. Sidney Post , Fifty-ninth Illinois Infantry, of operations May 3 - July 27 .

Atlanta, Ga., September 11, 1864 .

Captain: I have the honor to submit the following report of the operations of the Fifty-ninth Regiment Illinois Infantry while under my command in the campaign which has closed by our triumphant entry into Atlanta:

On the 3d day of May we left our camp at Blue Springs, Tenn., and on the 7th developed the enemy at Tunnel Hill, which they soon abandoned. From the 8th to the 12th of May the regiment was posted in front of Rocky Face Ridge, skirmishing with the enemy and constructing rifle-pits, and joined in the pursuit on the morning of the 13th , marching through Dalton. On the 14th we went into position before the enemy's works at Resaca, under a withering fire of both artillery and musketry, and remained within a few hundred yards of the enemy's works until the morning of the 16th , when we took possession of them. Again joining in pursuit of the retreating foe we crossed the Oostenaula River and came up with him in the evening at Adairsville. During the night he disappeared and we followed and found him at Kingston on the 19th . The Fifty-ninth Regiment, the advance of the corps, skirmished with the enemy in strong force on the road. from Kingston to Cassville until night. During the night he again retreated. On the 23d we marched from Cassville, crossed the Etowah River, and on the 25th we again confronted the enemy near Dallas. Until the night of the 5th of June we were building works and skirmishing constantly in the presence of the enemy, when he again abandoned his position. On the 6th we moved to Acworth, and on the 10th moved forward untii the enemy was found strongly posted on Pine Top, in front of which the regiment threw up rifle-pits. On the 15th the enemy abandoned Pine Top, which we immediately occupied. The regiment worked all the night of the 16th , under a furious fire from the enemy, building rifle-pits close to his works, but when day broke he again fell back. We followed him up and soon developed him in another line of works.

On the evening of the 20th the regiment constructed works within 300 yards of the enemy's line, under a heavy fire, the enemy having driven away the troops of the brigade on our right, and during the 21st and 22d we lay at that place under a continual fire of artillery and musketry. Having been ordered to move to the right on the 23d , we occupied a position in the immediate front of the enemy until the 3d of July , when he abandoned the line of the Kenesaw Mountain. The Fifty-ninth taking the advance threw out companies as skirmishers and pursued, driving the enemy's cavalry out of Marietta, and were the first Federal troops to enter that place. Leaving Marietta we pursued the foe five miles, to Ruff's Station, where we again came upon him in force, intrenched. On the 4th day of July , in accordance with orders received, the Fifty-ninth charged across the open field on the left of the railroad, driving the enemy from his rifle-pits, and permanently held them, with a loss of 4 killed and 16 wounded, including Adjutant Clark and Lieutenant Korhammer , of Company I, who was shot through the body while gallantly leading forward the skirmish line. The day was extremely hot and the men suffered dreadfully from thirst and exposure to the sweltering sun on that open field, but the position was held, and during the night the foe again fled. The next morning we moved to Vining's Station, where we lay in camp until the 9th, when the regiment was ordered to Powers' Ferry to observe the enemy. On the 12th we crossed the Chattahoochee and camped on the south side of the river near Powers' Ferry, where we lay until the 18th, when we moved forward to Buck Head. On the 19th , crossing Peach Tree Creek, we engaged in a lively skirmish and threw up works. On the 20th we moved toward Atlanta, encountered the enemy, and skirmished with him until he was driven within his permanent works about Atlanta on the 22d . Here we constructed substantial works, with carefully arranged abatis, and prepared for the final struggle for the possession of Atlanta. On the 27th of July I assumed command of the brigade, and the command of the regiment devolved upon Lieutenant-Colonel Hale .

The conduct of the officers and men of the regiment during this arduous campaign is deserving of the highest commendation; fearless in confronting the foe, energetic and cheerful in the laborious preparations of defenses, patient and persevering in their efforts to dislodge the enemy, they have at all times shown the highest qualities as soldiers and merit the thanks of their fellow-countrymen.

All the officers faithfully and intelligently executed my orders. From Lieutenant-Colonel Hale and Adjutant Clark I ever received prompt and reliable support. The soldierly bearing of Capt. D. W. Henderson , so conspicuously displayed on many of the battle-fields in which the regiment has been engaged throughout the several skirmishes and affairs of this campaign, demands special mention.

The loss sustained by the regiment while under my command was 14 killed and 46 wounded. Among the killed we mourn some of the most honored non-commissioned officers and privates in the regiment. I accompany this report with a list Omitted. of the killed and wounded.

I have the honor to be, very respectfully, your obedient servant,

P. Sidney Post, Colonel Fifty-ninth Regiment Veteran Infantry.

Captain Brinton , Acting Assistant Adjutant-General.