The valley of Olley's Creek was broad and open, and the country beyond my right was more practicable than the tangled wilderness on the northern slope of the watershed. We had got beyond the denser thickets of the loblolly pine, and could better see what we were about. The old Sandtown road south of Cheney's crossed the creek on a wooden bridge which was commanded by a fortified hill a little beyond where a battery of artillery swept the bridge and its approaches. The stream widened out after passing the bridge and ran between low and marshy banks with bluffs further back. I had placed Reilly's brigade astride the road at Cheney's with Myer's Indiana battery of light twelves, smooth-bore bronze guns. A gap of more than a mile lay between Reilly and the other three brigades of the division after I had marched to Hascall's support on the 22d. The lower branch of the Powder Springs road was parallel to the creek and not far from it, and my artillery near the right of the three brigades was on an advancing knoll where the guns not only commanded the valley before them, but Cockerill's Ohio battery of three-inch rifles swept nearly the whole space to Reilly's position. [Footnote: Id., p. 568.]
To give more effect to our demonstration, Sherman directed that it begin on the 26th, and preparations were made to build a bridge in front of Byrd's brigade, which was ordered to cross the stream when Reilly's effort against the lower bridge should begin. Our first information was that the fortified hill in front of Reilly was held by infantry, and as the work was in form a redoubt, its garrison of course on foot, we assumed that it was a detached outwork of the Confederate line. [Footnote: Official Records, vol. xxxviii. pt. iv. p. 597.] Reilly kept up a cannonade of the hill in front of him during the 26th, and made some attempts to get over the stream at the bridge, but did not seriously try to force the passage. A temporary bridge was laid at Byrd's position, and soon after noon he crossed the creek with little opposition, our artillery thoroughly commanding the further bank. [Footnote:Id., p. 599] I personally accompanied Byrd's movement. The artillery of Hascall's division as well as my own was turned on the enemy's works when they came out into the open. The hills along this part of Olley's Creek were not a continuous ridge, but knobby and somewhat detached; the higher land marking the edge of the plateau about Marietta was further back, and the Confederate line of works followed it. Byrd's direction of march was nearly parallel to the Sandtown road, and by advancing about a mile and a half he reached the summit of a rough wooded hill about six hundred yards from the main ridge, with open ground intervening. He was here from half a mile to a mile east of the Sandtown road, and from the fortified hill in front of Reilly, which was on the continuation of the same ridge, though with ravines interrupting it. The position was a very threatening one, and if any demonstration could draw the enemy in that direction, this seemed likely to do it. I directed Byrd to intrench on the crest, drawing back the flanks of the brigade so as to be ready for attack from any direction. Our movement had been sharply resisted by the enemy, but so far as we could see, only by dismounted cavalry. Sherman had said that he did not care to have Reilly force the passage of the creek that afternoon, for a strong threatening of the fortified hill would be more likely to draw the enemy that way than actually capturing it. [Footnote: Official Records, vol. xxxviii. pt. iv. p. 597.] On my reporting to General Schofield in the evening the position of Byrd's brigade with the favorable look of the country beyond, it was arranged that Byrd's bridge should be made stronger for permanent use, and that Cameron's brigade should follow him at daylight in the morning. With my whole division except Barter's brigade, which was left to cover Hascall's right flank, I was to test what further progress could be made on the Sandtown road. [Footnote: Id., pp. 598-600.]
At peep of day on the 27th we were astir, anxious to get our part of the day's work well advanced before the more serious engagement at the centre should begin. Another battery had been sent to Reilly, and he was directed to silence the enemy's guns and find a way across the creek under cover of his own if he could, but if this failed, to storm the bridge.
Cameron was over Byrd's bridge at four o'clock, and was ordered upon reaching the ridge in rear of Byrd to push boldly along it toward the fortified hill the other side of the Sandtown road in front of Reilly. Byrd's orders were to hold his position with the main body of his brigade, but to throw out detachments and skirmishers in all directions to watch the enemy and to get information of the country. Leaving Cameron as soon as he was well on his way, I rode to Reilly in front of the Cheney farm, and found that at five his dispositions for forcing the passage of the stream were well under way. He had determined to try it some distance below the bridge, at a place where, though the banks were swampy, the creek was fordable, and the hills behind gave good opportunity to use the artillery and put the men across under shelter. My chief of artillery, Major Wells, was with him, selecting places for the batteries and getting them in position. Soon after six I was with Cameron again, and before eight was back at Reilly's position, urging each to all the speed which the strong skirmishing opposition would permit. [Footnote: Official Records, vol. xxxviii. pt. iv. p. 619.] As it was necessary to pass from one position to the other by way of the roads at the rear, it made hard riding for one who wished to be as much as possible with the active heads of columns.
Soon after eight o'clock part of Reilly's brigade got over the swamp and creek under cover of the artillery, uncovering the bridge at the road where the rest crossed; Cameron's was now coming into close co-operation from the east, and a dashing charge by both carried the hill. [Footnote: Id., pt. ii. pp. 683, 703, 720.] It was now half-past eight, and the cannonade which preceded the attacks at the centre was opening heavily behind us. [Footnote: Id., pt. i. pp. 199, 632.] The captured position was a commanding one, and the view from it covered the whole region from Kennesaw to Lost Mountain. Cameron was left there whilst Reilly followed the retreating enemy with orders to advance as far as he could toward the Marietta and Sandtown road, which was supposed to come into the old Cassville and Sandtown road a mile or two ahead. We now knew from prisoners that the force opposed to us was the division of Confederate cavalry under Jackson, and that they were not closely supported by infantry.
The hill had been held by Ross's brigade, which retreated to another eminence half a mile further down the road. Reilly again advanced, supported by Cameron. Ross was again dislodged and retreated upon the rest of the division at the junction of the roads above mentioned. [Footnote: Id., pt. iv. pp. 799-801.] As we advanced it became evident that the principal ridge on which Johnston's army was broke down into separate hills as it came forward toward the forks of the main roads, and it seemed feasible to hold some of these in such a way as to make mutually supporting positions from Byrd to Reilly, covering a front of two miles and commanding the lower part of the Nickajack valley, in which the Marietta road ran. Reilly was put in one of these positions with his right across the road on which we had come, two miles south of Cheney's; Cameron was ordered forward upon high ground near Reilly's left, and Byrd was directed to straighten out his line on his right and reach as far as he could toward Cameron. All were ordered to intrench as rapidly and thoroughly as possible, for it was plain that we now commanded a short road to the railway in Johnston's rear, and that he must drive us out or abandon the Kennesaw line he had clung to so stubbornly.
I had sent my aide, Mr. Coughlan, with the orders to Byrd, and when the line was extended and skirmishers partly covered the front, he came back to me by a direct course from Byrd to Cameron and Reilly, with the daring and intelligence which made him a model staff officer, and reported that a continuous ridge connected the brigades so that pickets could be well placed in the interval to give warning of any hostile attempt to pass between. [Footnote: Official Records, vol. xxxviii. pt. iv. pp. 620, 621. Lieutenant Coughlan was afterward killed in the heroic performance of duty at the battle of Franklin. See "Franklin," p. 114.]A small hill a few hundred yards in front of the main line better commanded the Marietta road, and upon this I directed Reilly to build a lunette for an advanced guard of a regiment and a battery.
The whole affair was one of the minor class in war, but it had a special interest, in our ignorance of the topography of the country, because it revealed a way to Johnston's line of communications, which could not be seen and was not suspected when Sherman made the reconnoissance with us on the 25th, and saw the Confederate lines crossing the Powder Springs road and stretching away far beyond our right. In my field dispatch to General Schofield I said: "The possession of the end of the ridge, if we can hold it, I am now sure will prevent the enemy from extending his line along it, since it would be necessarily flanked and enfiladed by our positions. The only objection is the extension relatively to the strength of my command and the distance from supports. Upon carefully re-examining the ground my conviction is strengthened that it is exceedingly desirable to hold all we have gained, and if Hascall's place could possibly be filled by troops drawn from other parts of the line, it would give all the force needed to make a point-d'appui which would be safe and exceedingly available for future movements in this direction if they become necessary. I only suggest this by way of indicating the impression made on my own mind by the position." [Footnote: Official Records, vol. xxxviii. pt. iv. p. 621.]
Reilly was three miles distant from Barter's brigade, which covered the right of the continuous line of the army intrenchments, and it was certainly risking something to extend the brigades of a single division so far, but it would have been a great disappointment to us to have been called back. General Schofield instantly saw the advantage, and in answering my dispatch, said, "I do not think the importance of the position you have gained can be over-estimated, especially in view of the failure elsewhere and probable future movements." [Footnote: Ibid. See map, p. 255.] He ordered Stoneman's cavalry to aid me in holding the ground and in picketing the intervals, and reported to General Sherman the details of the operation. The latter determined to make use of the advantage gained, and said, "If we had our supplies well up, I would move at once by the right flank, but I suppose we must cover our railroad a few days." [Footnote: Dispatch to McPherson, Id., p. 622.] We were left, therefore, for a little while in our exposed position, whilst the whole army made strenuous efforts to get forward supplies enough for a few days' separation from the railway. The weather had begun to favor us. The day of the affair at the Kolb farm (22d) had been the first fair day of the month, and the continuous clear skies and hot suns rapidly dried the roads. Sherman sent Captain Poe to make an engineer's examination of our position and reconnoissance in front. The report confirmed his purpose of making us the pivot in a swinging movement of the whole army. On the 29th Generals Thomas and Howard accompanied General Schofield and myself in a similar inspection, to help fix the details of the movement for the Army of the Cumberland. Crittenden's brigade of dismounted cavalry reported to me for temporary duty as infantry with my division. On the 1st of July Hascall's division was relieved by the extension of Hooker's corps, and Schofield with his whole corps in hand advanced a mile upon the Marietta road toward Ruff's Mill. Johnston's failure to attack was proof that he was preparing for retreat, and Sherman pressed the movement of his own army.
On the 2d Johnston knew that McPherson's army was marching to interpose between him and the Chattahoochee, and issued his orders for the evacuation of the Marietta lines in the night, and the occupation of the position beyond the Nickajack. [Footnote: Official Records, vol. xxxviii. pt. v. p. 860.] But Thomas and McPherson both followed so vigorously that the Confederate general saw that he could not cover the crossings of the river which Stoneman's cavalry was already reaching on our right, and in the night of the 4th he again retired, this time to intrenchments with both flanks resting on the river and covering the railway bridge with two or three of the principal ferries. With his usual prudence, Johnston had prepared both these lines with the aid of the Georgia militia under General Gustavus W. Smith, who, being himself an engineer, was admirably fitted to co-operate with the plans of the staff.