Septimus Norris

Septimus Norris (1818 – 1862) was an American mechanical engineer and steam locomotive designer. He was the youngest of three brothers all active in the field — his eldest brother William Norris founded the Norris Locomotive Works of Philadelphia, Pennsylvania, and Richard Norris took over the firm in about 1841. The other two brothers were primarily businessmen, while Septimus was an engineer. He worked for the Norris firm under William's management, but did not continue under Richard's; railway historian John H. White, Jr. believes animosity existed between Septimus and Richard. Septimus later worked for the Portland Company and the Schenectady Locomotive Works.

He is frequently credited for the design of the first 4-6-0 locomotive, but in a paper written in 1885, George E. Sellers attributes the design to John Brandt, an engineer for the Erie Railway. White casts some doubt on Sellers' accuracy, and credits him in the development of coal-burning locomotives in the United States and as an early adopter of the more stable spread truck.

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