Thomas A. Scott, superintendent of the Pittsburgh division of the Pennsylvania railroad, took an aide with him when he went to Washington to become an assistant secretary of war. Speaking with a soft Scottish burr, his twenty-six year old companion quickly showed himself to be an expert in telegraphy. Soon Andrew Carnegie was put to work coordination rail and telegraph lines of the Union.
Serving as a civilian executive in the military transportation section of the War Department, Carnegie was never forced to dodge Confederate bullets. He considered establishment of the telegraph office frequented by Lincoln to be one of his greatest contributions to the war effort.
Entering the iron and steel business in 1865, within one-quarter of a century he had gained controlling interest in the U.S. Steel Corporation. Then the former worked for the War Department sold out and devoted the rest of his life to distributing his fortune among countless public libraries and other charitable enterprises.