In Schofield’s extension on the 5th, General Reilly’s brigade had struck an outwork, which he promptly attacked, but, as usual, got entangled in the trees and bushes which had been felled, and lost about five hundred men, in killed and wounded; but, as above reported, this outwork was found abandoned the next day, and we could see from it that the rebels were extending their lines, parallel with the railroad, about as fast as we could add to our line of investment.  On the 10th of August the Parrott thirty-pounders were received and placed in Position; for a couple of days we kept up a sharp fire from all our batteries converging on Atlanta, and at every available point we advanced our infantry-lines, thereby shortening and strengthening the investment; but I was not willing to order a direct assault, unless some accident or positive neglect on the part of our antagonist should reveal an opening.  However, it was manifest that no such opening was intended by Hood, who felt secure behind his strong defenses.  He had repelled our cavalry attacks on his railroad, and had damaged us seriously thereby, so I expected that he would attempt the same game against our rear.  Therefore I made extraordinary exertions to recompose our cavalry divisions, which were so essential, both for defense and offense.  Kilpatrick was given that on our right rear, in support of Schofield’s exposed flank; Garrard retained that on our general left; and McCook’s division was held somewhat in reserve, about Marietta and the railroad.  On the 10th, having occasion to telegraph to General Grant, then in Washington, I used this language: 

Since July 28th Hood has not attempted to meet us outside his parapets.  In order to possess and destroy effectually his communications, I may have to leave a corps at the railroad-bridge, well intrenched, and cut loose with the balance to make a circle of desolation around Atlanta.  I do not propose to assault the works, which are too strong, nor to proceed by regular approaches.  I have lost a good many regiments, and will lose more, by the expiration of service; and this is the only reason why I want reenforcements.  We have killed, crippled, and captured more of the enemy than we have lost by his acts.

On the 12th of August I heard of the success of Admiral Farragut in entering Mobile Bay, which was regarded as a most valuable auxiliary to our operations at Atlanta; and learned that I had been commissioned a major-general in the regular army, which was unexpected, and not desired until successful in the capture of Atlanta.  These did not change the fact that we were held in check by the stubborn defense of the place, and a conviction was forced on my mind that our enemy would hold fast, even though every house in the town should be battered down by our artillery.  It was evident that we most decoy him out to fight us on something like equal terms, or else, with the whole army, raise the siege and attack his communications.  Accordingly, on the 13th of August, I gave general orders for the Twentieth Corps to draw back to the railroad-bridge at the Chattahoochee, to protect our trains, hospitals, spare artillery, and the railroad-depot, while the rest of the army should move bodily to some point on the Macon Railroad below East Point.