In the Federal army a great change had taken place. General Buell had been relieved from command, and General W. Rosecrans, the hero of the battle of Corinth, appointed in his place. This general assembled his army at Nashville. Thus the two great armies were only thirty-two miles apart, with their outposts almost touching. Bragg, believing that it would be impossible for Rosecrans to advance before spring, established his army in winter quarters, and the soldiers looked forward to two or three months of comparative quiet. Rosecrans’s first duty was to reopen the Louisville and Nashville Railroad, which had been so thoroughly destroyed by Morgan. An army of men did the work—a work which took them weeks to accomplish. But it was not in the nature of Morgan to be quiet. Not only he, but his men, fretted in camp life. Its daily routine with its drills did not suit them. Their home was the saddle, and they wanted no other. Therefore Morgan began to look around in search of a weak point in the Federal lines. For this purpose Calhoun and his scouts were kept busy. They seemed to be omnipresent, now here, now there. They would ride in between the Federal posts, learn of the citizens where the enemy were posted, and whether their camps were guarded with vigilance or not. Many a prisoner was picked up, and much valuable information obtained. In this way Morgan soon knew, as well as the Federal commander himself, how his troops were posted, and the number at each post. Taking everything into consideration, Calhoun reported that Hartsville offered the best opening for an attack. “It is the extreme eastern outpost of the Federals,” he said. “The nearest troops to them are at Castalian Springs, nine miles away. The country from here to Hartsville is entirely free of Federal troops, and we can approach the place unobserved. The Cumberland River is low and can be forded. But if you wish, I will go and make a thorough reconnaissance of the place.” “Go, and be back as soon as possible,” replied Morgan, “but be careful; do not take too many risks.” With a dozen of his trusty scouts, Calhoun had no trouble in reaching the bank of the Cumberland River opposite Hartsville. Here, concealed in the woods, through his glass he noted the position of every regiment, and drew a map of the camp. But he was not satisfied with this. Under the cover of darkness he crossed the river, determined to learn more. Above all, he wished to learn where the enemy’s pickets were posted at night, their exact force, as nearly as possible, and the discipline which they were under. He wanted to do all this without alarming them.