Simultaneously with the appearance of Breckinridge in the Kelly field events were hastening to an appalling consummation on the Union center. Stewart, the right of Longstreet's wing, moved to the assault in Reynold's front. With three brigades he rushed upon Turchin, who formed Reynold's advance, and Hazen, of Palmer, next on the left, while his left also involved Brannan's left. On his right he also had the co-operation of Wood's and Deshler's brigades, of Cleburne. Deshler was killed as the movement began, and Roger Q. Mills, of Texas, succeeded him.
As this was the opening of the memorable attack which led to the break in the Union center it is worthy of close attention. General Stewart, in his report, thus describes it:
"For several hundred yards both lines pressed on under the most terrific fire it has ever been my fortune to witness. The enemy retired, and our men, though mowed down at every step, rushed on at double-quick, until at length the brigade on the right of Brown broke in confusion, exposing him to an enfilading fire. He continued on, however, some fifty to seventy-five yards further, when his two right regiments gave way in disorder and retired to their original position. His center and left, however, followed by the gallant Clayton and indomitable Bate, pressed on, passing the cornfield in front of the burnt house, and to a distance of two hundred to three hundred yards beyond the Chattanooga road, driving the enemy within his line of intrenchments and passing a battery of four guns, which were afterward taken possession of by a regiment from another division. Here new batteries being opened by the enemy on our front and flank, heavily supported by infantry, it became necessary to retire, the command reforming on the ground occupied before the advance."
All this was going on in the front of Reynolds and Palmer, while Breckinridge, as already described, was entering the open field from the north in plain sight from their rear. Yet not a single Union soldier left the line. Standing steadfast, they first resisted, as Stewart describes, and then were incited to still greater action by the brilliant fighting of Van Derveer in their rear, which so unexpectedly brought them the much-needed relief.
Here the story reaches the event of the break in the Union lines, which is widely misunderstood, and has been most unjustly used to throw discredit on General Rosecrans. Just as Longstreet's attack was developing upon Wood's front, the latter received an order from General Rosecrans to "close upon Reynolds as fast as possible and support him." As Brannan was between himself and Reynolds, Wood saw no other way of executing the order, which he deemed imperative, except to withdraw from line, and pass to the rear of Brannan. This he did, although the attack was just bursting on his front.
It has been persistently claimed, to General Rosecrans's detriment, that in the excitement of the height of battle he had issued a blundering order. Nothing could be more unjust. The explanation is perfectly simple. General Thomas had sent for Brannan to meet Breckinridge's flank attack. Stewart's attack had struck Reynolds with force and was rapidly developing on Brannan's front. The latter hastily consulted with Reynolds as to the propriety of withdrawing, and both being clear that to obey the order would open the line to the enemy, Brannan dispatched Van Derveer, his reserve, to the left, in partial compliance with its terms, and then reported to Rosecrans that he had deemed it vitally important to maintain his line till the commanding officer could be advised of the situation. He instantly approved Brannan's action. But just before his message arrived, upon the supposition that he had obeyed the order and gone to Thomas, the noted order to Wood to close to the left on Reynolds had been dispatched. When it reached Wood, the attack, rolling along Brannan's front, had reached his own. Had he exercised the same discretion which Brannan had so wisely displayed, all would have been well, and that nearly fatal break in the Union lines would not have occurred. But instantly on reading it, Wood rapidly withdrew his division and started in the rear of Brannan toward Reynolds. Longstreet, who had waited most impatiently till 11 o'clock before he could move a man to the attack, had solidified his lines before the Union center and left, and the moment Wood left this wide gap for him, Longstreet thrust into it the eight brigades of his central column of attack. They were formed in three lines, and advancing rapidly they opened on Brannan's right and rear and Davis' left, and greatly widened the gap. Brannan threw back his right, losing something from Connell's brigade on that flank, but, stubbornly resisting Longstreet's advance as he retired that wing of his division, he soon re-established it on Horseshoe Ridge, near the Snodgrass House, on a line nearly perpendicular to the one he had occupied when Longstreet pushed through the gap left by wood. The latter had passed rapidly to the rear of Brannan, and though subjected to heavy attack after passing Brannan's left, he was able to establish his line on a lower ridge in the prolongation of Brannan's new position, and reaching in the direction of Reynolds. The latter officer soon retired his right slightly, and the line was again continuous, except a break between Wood and Reynolds, from Brannan's right to Barnes on Baird's left. Into this vacant space Hazen moved later under orders from Thomas, and then the line on that part of the field was firmly established.
All to the right of Brannan had gone. Negley, with one brigade of his division, which was caught in the gap, had drifted toward Brannan. Here, gathering up much artillery, which he was ordered by Thomas to post on the crest overlooking the field in front of Baird's left, he took it instead to Brannan's right, and soon, without waiting to be attacked in his strong position, and although he had promised Brannan to hold it, abandoned it, and retired in haste toward Rossville, ordering all the artillery to follow him.
Davis had moved rapidly into the breastworks which Negley had occupied, and there placed his weak force of two brigades across Longstreet's advance. But after his terrific fighting of the day before he had only twelve hundred men for action, and though Carlin, and Heg's men under Martin, fought with desperation, they could do nothing but yield. They were driven in disorder to the right and rear.
At the same time Van Cleve, with his two remaining brigades in motion towards Thomas, was thrown into great disorder, though a considerable portion of them rallied with Wood.
As Davis was borne back, McCook, of the Twentieth Corps, in person led Laiboldt's brigade, of Sheridan's division, against Longstreet's advancing columns. The attack was delivered with spirit and power, but it failed in the face of overwhelming numbers, and the brigade was utterly routed. McCook was carried to the rear with it.