August 28, 1830 – The Baltimore & Ohio Railroad’s new Tom Thumb steam locomotive races a horse-drawn car, presaging steam’s role in US railroads.
Designed and constructed by Peter Cooper in 1830, it was built to convince owners of the newly formed B&O to use steam engines and not intended to enter revenue service. In the race between the horse and the Tom Thumb, the horse was the winner after the locomotive suffered a mechanical failure. However, the demonstration was successful; and in the following year, the railroad committed to the use of steam locomotion and held trials for a working engine. (Wikipedia)
In 1987, The Commonwealth of Dominica issued a 45-cent stamp commemorating the race (Michel Catalog #DM 1055):