It was of the utmost importance to the Confederacy that the new line of defence should be held, in order to control one of the principal means of communication with the Atlantic States, by which the army and the people were to be supplied with food. This line included several important railway junctions, from which roads extended down to New Orleans and Mobile. From Chattanooga a road passed through Eastern Tennessee, then in possession of the rebels, to Virginia, being the most direct route to Richmond; and another went to Atlanta, where lines diverged to the east, west, and south, by which all the southern and eastern cities of the Confederacy were reached. The new defensive line was established, and strengthened with all the men and material which the resources of the Confederacy would admit. The ablest and most experienced generals in its service were sent to the command of the rebel armies there. The presence of both Albert Sidney Johnston and Beauregard attested the importance with which the rebel leaders regarded this line; for, driven from it, another move to the south would drive them down to within two hundred miles of the Gulf of Mexico. This line had now become the objective point of the Union generals in the West. On the day following the surrender of Fort Donelson, General Grant issued his first order, taking command of the new military district of West Tennessee, whose limits, however, were not defined in his appointment by General Halleck. General Smith, whom Grant still regarded as his "right-hand man," and whom he had already strongly recommended for promotion to the rank of major general, was sent fifty miles up the Cumberland, to occupy Clarksville. The timid counsels of Halleck restrained and annoyed the commander of the new district. His superior was constantly prating about the risk of a general battle, and urging extreme caution. General Buell, in command of the Department of the Ohio, who had occupied Bowling Green, now moved forward and occupied Nashville. As Grant's district limits had not been defined, he visited Nashville for the purpose of consulting Buell in regard to this subject and the disposition of the troops of the two armies. In the mean time, by the order of General Halleck, Grant was engaged in organizing an expedition to go up the Tennessee River, to attack the rebel line of defence, and cut the communications at Corinth, Mississippi--the junction of the Mobile and Ohio with the Memphis and Charleston Railroads. While these preparations were in progress, Halleck sent a growling complaint to Washington, which I cannot help transcribing here, though more to show the excellent spirit of Grant under the most terrible provocation, than to exhibit the littleness of Halleck:--