Stevens, U.S. family of inventors and engineers. John (1749–1838) built the first steamboat with a screw propeller (1802) and the first seagoing steamboat (1809). He also built the first U.S. steam locomotive (1825). His son Robert Livingston (1787–1856) invented the inverted T-rail still used in modern railroads (1830). Another son, Edwin Augustus (1795–1868), also made contributions to railroad technology.
See also: Railroad.