The Photographic History of The Civil War: in ten volumes, Thousands of Scenes Photographed 1861-65, with Text by many Special Authorities, Volume 5: Forts and Artillery.
Francis Trevelyan Miller, Ed.

[296] previously felt elsewhere. On June 28, 1863, Hooker was relieved by General Meade. The crucial period of the war came at Gettysburg. The construction corps, under the personal direction of General Haupt, rendered invaluable service. Haupt had made Gettysburg his home for part of the time he was a resident of the State of Pennsylvania, and knew every road in the vicinity. He gave great assistance in divining Lee's direction of march, and by the great exertions of the corps the railroad communications were kept open, the wounded handled with celerity, and after the battle there was a sufficient supply on hand of nearly all kinds of provisions.

On September 14, 1863, General Haupt was relieved from further duty in the War Department, and turned over his work to Colonel D. C. McCallum, who was appointed superintendent of military railroads. The efficient operation of the roads with the Army of the Potomac continued, and received the enthusiastic praise from General Grant which already has been noted.

Extensions aggregating nearly twenty-two miles in length were built to the railroad from City Point, in order to supply Grant's forces in the lines before Petersburg. After the repulse of General Rosecrans at Chickamauga, in September, 1863, it was deemed necessary to send reenforcements from the Eastern armies, and the military-railroad officials were called upon to know if the movement of the number of troops designated was practicable. Colonel McCallum soon gave an affirmative answer, and the result was the transfer of Hooker, with two corps, about twenty-two thousand men, over twelve hundred miles in eleven and one-half days. For this service Colonel McCallum was appointed brevet brigadier-general.

The Knoxville-Chattanooga road was the next to be opened, and then the Nashville-Johnsonville line. In all of this work the corps introduced new methods to replace the older ones. All of this was preparatory to the advance on Atlanta, in 1864.