Late in the summer, General Rosecrans resumed operations, and marched upon Chattanooga, while General Burnside moved into East Tennessee, and obtained possession of Knoxville. General Burnside’s march was one of the most difficult ever made in war, and tasked the powers of his men to the utmost; but all difficulties were surmounted, and the loyal people of the country which he entered and regained were gladdened by seeing the national flag flying once more over their heads. Both these movements were at first brilliantly successful; but the enemy were impressed with the importance of the points taken or threatened by our forces, and they concentrated great masses of troops, in the hope of being able to defeat our armies, regain the territory lost, and transfer the seat of war far to the north. The Battle of Chickamauga was fought, and a portion of General Rosecrans’s army was defeated, while another portion, under General Thomas, stubbornly maintained its ground, and inflicted great damage on the enemy. The effect of General Thomas’s heroic resistance was, that the enemy’s grand purpose was baffled. Their loss was so severe, and their men had been so roughly handled, that they could not advance farther, and the time thus gained was promptly turned to account, by General Rosecrans in the first instance, and by Government. The Union army was soon reorganized by its energetic leader, and placed in condition to make effectual resistance to the enemy, should they endeavor to advance. The Government’s action was rapid and useful. General Grant was placed in immediate command of the army, which was largely reinforced, and preparations were quickly made for the resumption of offensive operations. In the mean time, General Bragg had sent General Longstreet to attack General Burnside; and as Longstreet has been looked upon, since the death of Jackson, as the best of the Rebel fighting generals, great hopes were entertained of his success. Apparently taking advantage of the absence of so large a body of Rebel troops under so good a leader, General Grant resumed the offensive on the twenty-third of November, and during three days’ hard fighting inflicted upon General Bragg a series of defeats, in which Generals Thomas, Hooker, and Sherman were the active Union commanders. The Unionists were completely victorious at all points, taking several strong positions,