Peter Cooper’s early American locomotive that raced and lost against a horse in 1830 was Tom Thumb.
Cooper designed and built Tom Thumb in 1829 to persuade the newly formed Baltimore and Ohio Railroad that steam locomotives could work on its line. It was a compact experimental engine with a vertical boiler and vertically mounted cylinders, rather than a mature locomotive design intended for regular revenue service.
The famous race probably took place near Baltimore on August 28, 1830, although historical accounts give other dates. Tom Thumb initially pulled ahead of the horse-drawn car. It then suffered a mechanical failure when a belt driving the blower slipped off. Without the blower, the boiler could not produce steam effectively, allowing the horse to win.
The defeat did not undermine the demonstration. The locomotive’s performance convinced the B&O to pursue steam power, and the railroad stopped using horses for its main operations in 1831. Tom Thumb was later remembered through drawings and a 1927 replica; the original locomotive did not survive intact.