LEFT WING, LIEUTENANT-GENERAL LONGSTREET COMMANDING.
Buckner's corps, Major-General Buckner: Stewart's division, 4 brigades, 4 batteries; Preston's division, 3 brigades, 3 batteries; Johnson's division, 2 brigades, 2 batteries.
Longstreet's corps, Major-General Hood: McLaws' division, 2 brigades; Hood's division, 3 brigades; Hindman's division, 3 brigades, 3 batteries; Reserve artillery, 5 batteries.
Total of wing, 6 divisions, 17 brigades, 17 batteries.
Total in both wings, 11 divisions, 33 brigades, 33 batteries.
Corps of cavalry, Major-General Wheeler, operating on Bragg's left: Wharton's division, 2 brigades, 1 battery; Martin's division, 2 brigades, 1 battery.
Corps of cavalry, Major-General Forrest, operating on Bragg's right: Armstrong's division, 2 brigades, 2 batteries; Pegram's division, 2 brigades, 2 batteries.
Total of cavalry, 4 divisions, 8 brigades, 6 batteries.
ROSECRANS' ARMY.
Fourteenth corps, Major-General Thomas commanding: Baird's division, 3 brigades, 3 batteries; Negley's division, 3 brigades, 3 batteries; Brannan's division, 3 brigades, 3 batteries; Reynolds' division, 3 brigades, 3 batteries.
Twentieth corps, Major-General McCook commanding: Davis' division, 3 brigades, 5 batteries; Johnson's division, 3 brigades, 3 batteries; Sheridan's division, 3 brigades, 3 batteries.
Twenty-first corps, Major-General Crittenden commanding: Wood's division, 3 brigades, 3 batteries; Palmer's division, 3 brigades, 4 batteries; Van Cleve's division, 3 brigades, 3 batteries.
Reserve corps, Major-General Granger commanding: One division, 3 brigades, 3 batteries.
Total, 11 divisions, 33 brigades, 36 batteries.
Cavalry corps, Brigadier-General Mitchell commanding: 2 divisions, 5 brigades, 2 batteries.
The number of infantry divisions and brigades, as reported, was the same in both armies. Bragg had more cavalry in the field than Rosecrans, but in the battle of Chickamauga, on his immediate flanks, Wheeler had not more than 2,000 and Forrest about the same number. It is always difficult to estimate the strength of armies by counting their divisions, brigades or regiments, for the reason that it is impossible in an active campaign to keep up the relative proportions of separate corps, engaged at different times and often with no option as to whether a fresh or a decimated command shall go into action. The writer was an officer of General Walker's division, and knows that at the battle of Chickamauga, on the 20th, that division of three brigades did not number 3,000 men. General Gist's brigade, to which the writer was attached, went into action on the 20th, 980 strong, one of its regiments (Sixteenth South Carolina) and its light battery being absent at Rome.
By studying the field returns of both armies, nearest to the opening battle on the 19th (Rosecrans' of September 10th and Bragg's of August 20th), and making deductions for commands on stations or on detached duty, and counting in for Bragg's army the two divisions from Mississippi (Breckinridge's and Walker's), and Longstreet's five brigades and Buckner's troops, and estimating losses for both armies up to the battle of the 19th, it is believed that Bragg crossed the Chickamauga on the 18th, 19th and 20th with 45,000, exclusive of his cavalry. By the method of estimating the strength of General Bragg's army, the writer believes that Rosecrans confronted Bragg with 53,000, exclusive of his cavalry.
Before the battle, each general overestimated the strength of the other and underestimated his own. On September 12th, General Rosecrans believed that "the main body of Johnston's army had joined Bragg," and that he had been heavily reinforced from Virginia. The truth is, that so far as Bragg's reinforcements affected the engagements of the armies at Chickamauga, they did not add a man more than 10,000 to Bragg's strength, if, indeed, they added so many.
The two armies facing each other from opposite sides of the Chickamauga, Bragg gave order for battle. Rosecrans' left, under Thomas, was at Kelly's house on the Chattanooga road, his right stretching beyond and south of Lee & Gordon's mills. The Chattanooga road spoken of is the main road from LaFayette to Chattanooga, crossing the Chickamauga at Lee & Gordon's mills. Kelly's house was opposite Reed's bridge, and south of it, on the road, were the houses of Poe, Brotherton, Brock, Taylor and Vineyard. Nearly a mile north of Kelly's was McDonald's. From McDonald's to Lee & Gordon's mills (the road running nearly north and south) was about 4 miles.
The crossings of the Chickamauga were by fords and two bridges, Alexander's and Reed's; the former opposite Vineyard's house, and the latter opposite Kelly's. Hunt's (or Dalton's) ford came nearest Lee & Gordon's mills; then Thedford's, then Alexander's bridge, then Byram's ford, then Reed's bridge, and a mile further north, Reed's ford. General Bragg's order designated the ford or bridge at which the different commands were to cross and directed each to attack in front, beginning from the Reed bridge crossing and moving against the Federal left and rear.
Thomas marched his head of column beyond Kelly's house, faced the Chickamauga, and sent one of his divisions (Brannan's) to reconnoiter toward Reed's bridge. From Kelly's to Reed's bridge was about 2½ miles. At Jay's mill, near the bridge, Brannan met Forrest, and the battle of the 19th was opened. Forrest pushed Brannan back, the latter was reinforced by Baird's division, and Walker (marching from Alexander's bridge toward Forrest's battle) sent two of his brigades, Ector's and Wilson's, to Forrest's support. Brannan and Baird were driving Forrest back to Jay's mill when Ector and Wilson came up, and then in turn Baird and Brannan were driven, artillery and prisoners captured. Thomas now reinforced his battle by Reynolds, and McCook sent in Johnson's division. Walker, coming up with Liddell's two brigades, took command of the battle and attacked vigorously with Forrest and his four brigades, driving Reynolds, on the Federal right, in rout; but Palmer's division sent by Crittenden to reinforce Thomas, met and drove Walker back. Meanwhile, Baird and Brannan were checking and holding Forrest.