His sober, technical, methodical, and non-ideological personality had an important influence on the Pennsylvania Railroad, which in the mid-19th century was on the technical cutting edge of rail development. The railroad was known for its conservatism and steady growth while avoiding financial risks. His Pennsylvania Railroad became the largest railroad in the world, with 6000 miles of track, and was notable for generating steady financial dividends, for high- quality construction, constantly improving equipment, technological advances (such as replacing wood with coal as locomotive fuel), and innovation in management techniques for a large complex organization.