In considering Sherman's means of supplying his army in the field, we must note the situation and connections of Nashville, which made it naturally the principal depot for operations in Alabama and Georgia. A hundred and eighty-six miles by rail south of the Ohio River, centrally situated as the capital of Tennessee, it was directly connected with Chattanooga by a hundred and fifty miles of railroad, and indirectly by way of Decatur, Alabama, and Stevenson, a line thirty-five miles longer. These railway connections would of themselves make Nashville an important post, but it had also the advantage of water communication with the Ohio. It lies at the southern bend of the Cumberland River, the course of which is nearly due north from the city to its mouth, and the stream is navigable for steamboats the greater part of the year. The Tennessee, a much larger river, is nearly parallel to the Cumberland in this part of its course, and a partially constructed railroad from its banks at Johnsonville to Nashville, seventy-odd miles, was completed during the winter. With these three lines of communication, there was very little danger that the great Nashville depot could run short of munitions or rations, or be seriously isolated by raids of the enemy. It was to communication between Chattanooga and Nashville that Sherman had to give his best thought and will. The War Department had sent out Colonel McCallum, the General Superintendent of Military Railways in January, and improvements had then been begun, which under Sherman's energetic command made a brilliant success of this part of the military administration through the whole campaign. [Footnote: See "Sherman" (Great Commanders Series), pp. 199 _et seq_. Also letter of McCallum to Stanton, Official Records, vol. xxxii. pt. ii. pp. 143-145: Order appointing Adna Anderson general superintendent of transportation and W. W. Wright chief engineer of construction, _Id_., p. 365: Sherman's order organizing the military use of the railways, _Id_., pt. iii. p. 279.] The management of the railways in use was given to Adna Anderson, and the engineering and bridge-construction to W. W. Wright. These gentlemen were both civil engineers and experts in railroad building and management. Military rank was given them later in order to enable them to control officers and men of the army on proper occasions. Their skill and energy were of inestimable value to the army, and gave them brilliant reputations which they fully earned. They remained in their military railway duties to the end of the war, and were distinguished in the same profession in civil life to the end of their lives. When Sherman assumed command of the Division of the Mississippi, about eighty carloads a day was the limit of the capacity of the road and the delivery at Chattanooga. It was only half of what was needed to insure rapid progress of the campaign. By the 1st of May it had increased to a hundred and thirty