Bragg made no effort to prevent this concentration of the Union forces, and during the night of September 17 the three corps were within supporting distance of each other. The Union left was at Lee and Gordon’s Mills, and from there the line extended west and south through McLemore’s Cove to Stevens Gap through Lookout Mountain. _The Battle of Chickamauga_ Chafing over the failure of his subordinate commanders to strike the divided units of Rosecrans’ army and wishing to seize the initiative, General Bragg had his troops do an “about face.” Turning northward, he planned an all-out attack on General Crittenden who had been following in his rear since the evacuation of Chattanooga and was now at Lee and Gordon’s Mills. General Bragg moved his troops northward on the east side of the Chickamauga Creek. His plan was to cross the Chickamauga north of Lee and Gordon’s Mills, seize the roads leading to Chattanooga, bear down on Crittenden, and crush this corps or drive it back into the Union center in McLemore’s Cove. By turning the Union left in this manner, he hoped to force Rosecrans back into the mountains and to reoccupy Chattanooga. Maj. Gen. John B. Hood (Longstreet’s Corps) and Brig. Gen. Bushrod Johnson’s troops were to cross at Reeds Bridge and turn left; Walker’s Corps to cross at Alexander’s Bridge; Buckner to cross at Tedford’s Ford; Lt. Gen. Leonidas Polk’s Corps to cross at Lee and Gordon’s Mills; and Hill’s Corps to cover the Confederate left. Bragg did not seem to suspect that Rosecrans had guessed his intentions, and was hurriedly moving to support Crittenden and deploying his troops so as to protect the roads to Chattanooga. SEPTEMBER 18—PRELIMINARIES. On the morning of the 18th the three advanced brigades of Longstreet’s Corps from Virginia arrived at Ringgold. One brigade immediately joined Bushrod Johnson’s division as it prepared to cross Chickamauga Creek at Reed’s Bridge. Union cavalry under Col. Robert H. G. Minty and mounted infantry under command of Col. John T. Wilder, guarding the bridges, offered stout resistance and delayed the crossing of the southern troops for several hours. During the skirmishing, Minty’s men dismantled Alexander’s Bridge and forced Walker to proceed to Lambert’s Ford, a half-mile downstream. The Confederates used other fords and crossings throughout the late afternoon and night as all of Bragg’s forces, except three divisions, crossed to the west side of Chickamauga Creek.