Topographical Plan of the Battlefield, from the Official Map.

[Ed. Note: The original of this map was made immediately after the battle from surveys and information obtained by Chief of Topographical Engineers George Thom (of Halleck's staff) and his assistants, while the troops were still encamped on, and near, the battlefield. The positions of the troops were indicated in accordance with information at the time by Generals Grant, Buell, and Sherman.

The Confederates moved to the attack in three lines of battle: (1.) Hardee's three brigades and Gladden's brigade of Bragg's Corps forming the advance line, reaching from Sherman's right to beyond Prentiss's left; (2.) Bragg's remaining five brigades about eight hundred yards in rear of Hardee's line and bearing off more to the right, as far as Stuart; (3.) Polk's four brigades and Breckenridges three brigades disposed left and right as reserves, -- Polk's first to be drawn upon.

Hardee's line carried the first Federal position, and with the assistance of Bragg's line, fought the Federals back nearly a mile, where, at 10:30 o:clock, the Federal line extended, in general, from what is indicated as McCook's position on the morning of the second day, across to what was Sherman's position the morning of the second day. The Federal line was maintained until after four o:clock in the afternoon. Attacking that line, Polk's brigades were, for the most part, on the right of Hardee, who was then commanding the Confederate left; Bragg directed the attack on Polk's right; and two of Breckenridge's three brigades were in the main hotly engaged on the Confederate right.

Toward evening the Confederates were arrayed opposite the Federal line, as indicated for the evening of April 6.

The center of the left on the middle line of defence (which was held from 10:30 till after four o:clock) was called by the Confederates "The Hornets' Nest." It was, approxiametely, the ground indicated as having been held by McCook on the morning of April 7; on April 6 it was defended by Prentiss, assisted on his right by W.H.L. Wallace, and on his left by Hurlbut. Prentiss was not far from the Hornet's Nest when he was captured.

General Johnston was killed at 2:30, Sunday afternoon, on ground indicated as having been held by Crittenden on the morning of April 7.]