John Edgar Thomson (February 10, 1808- May 27, 1874) was an American civil engineer and industrialist. He is best known for his leadership as the third president of the Pennsylvania Railroad from 1852 until his death in 1874.

 

Thomson was trained as a surveyor and joined the Pennsylvania Engineer Corps at age 19 to assist with laying out the route of the state’s Philadelphia and Columbia Railroad. By 1830, he became head of the engineering division for the Camden & Amboy Railroad in New Jersey.  From 1832 to 1847, he served as chief engineer for the Georgia Railroad, which built an Atlanta-to-Augusta line, the longest line built by one company up to that time. These accomplishments lead to his hiring as the first Chief Engineer of the Pennsylvania Railroad.

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Thomson was promoted to president of the PRR in 1847.  As president, he extended the Pennsy westward through Ohio, Indiana, and Illinois.  By the time of his death, the railroad reached from New York, Philadelphia, Baltimore, and Washington in the east to Pittsburgh, Buffalo, Cleveland, Cincinnati, Indianapolis, Louisville, St. Louis, and Chicago in the west. Thomson also introduced important improvements, including a system for handling passenger baggage and the use of steel rather than iron rails.

Thomson built the Pennsy into the largest business enterprise in the world and a world-class model for technological and managerial innovation.