Rosecrans was led to believe that Bragg was in full retreat to Rome and
Atlanta. He had gathered this information from pretended deserters from
the Confederate army. However, he was determined to head the
Confederates off. He immediately dispatched Thomas and McCook down
Lookout Valley to point 26 and 42 miles below Chattanooga where they
crossed Lookout Mountain. Thomas moved into McLemore’s Cove; McCook to
Alpine and Summerville, Georgia. In planning these movements and making
such disposition of his troops, Rosecrans was falling into a trap which
had been set for him. Bragg’s army was not in retreat. They had no
intentions of retreating. Rosecrans was not aware of the fact that Bragg
was not in retreat until about September 12th. His army was divided into
three sections. It was at least 60 miles from the left to right of his
troops. Meanwhile, Bragg at LaFayette, was opposite the Union center and
in position to attack and crush the Union army in detail as they emerged
from the mountains. He had already been re-enforced by Buckner from east
Tennessee and Walker from Mississippi. He was only awaiting Longstreet’s
arrival from Virginia before turning back in an effort to retake
Chattanooga. The latter named troops were seasoned veterans who were
sent down by Gen. Lee. A great many of them had fought in the battle of
Gettysburg. Upon their arrival Bragg ordered the Confederates to turn
back toward Chattanooga. His plan was to attack Crittenden and in case
Thomas and McCook should arrive they could be taken care of, likewise,
in order. Failure of his subordinate officers to comply promptly with
these orders caused this opportunity to be lost. Rosecrans, upon
learning that Bragg had received heavy re-enforcements and was turning
back in an effort to retake Chattanooga, hurriedly ordered the
concentration of his forces. McCook, contrary to orders, took a
roundabout route from Summerville, causing some delay. However, on
September 17th, he joined Thomas and they in turn started their movement
to join Crittenden. At this time Crittenden was on the west side of
Chickamauga Creek at Lee and Gordon’s Mill. It was necessary for Thomas
and McCook to make a forced march day and night in order to reach
Crittenden. They were practically exhausted when they reached him.