Bush, a graduate of Stevens Institute of Technology, had worked his way up from apprentice mechanic at the locally based Pittsburgh, Cincinnati, Chicago and St. Louis Railroad to superintendent of motive power at that railroad, and, briefly, the Milwaukee Road. In 1908, Rockefeller departed, and Bush took over as president, a job he would hold until 1928.
Bush, who had graduated from Stevens Institute of Technology, began his career as an apprentice mechanic for the Pittsburgh, Cincinnati, Chicago and St. Louis Railroad before becoming superintendent of motive power at that railroad. He also briefly served as president of the Milwaukee Road. In 1908, Rockefeller left the company, and Bush took over as president, a position he held until 1928.