British engineer and pioneer in the field of locomotion.

Trevithick was educated at Camborne School, Cornwall. By 1795 he was receiving pay for fuel savings resulting from his improvements to a steam engine at Wheal Treasury mine. As early as 1796 he had made models of steam locomotives which he showed to friends at Camborne. In 1797 he was appointed engineer at Ding Dong mine near Penzance, trying to make improvements in the engine design developed by William Bull. He also set up one of Bull's engines at the Herland Mine in rivalry with one of Watt's best engines.

In 1800 Trevithick built a highly ingenious, double-acting, high-pressure engine for Cook's Kitchen mine, and this economical type of engine, known as a 'puffer' after the steam it expelled into the atmosphere, was soon in demand in Cornwall and South Wales for raising ore and spoil from the mines.

Trevithick built an experimental locomotive with passengers in 1801, known locally as 'puffing devil' or 'Captain Dick's puffer'. The introduction of the high pressure principle as outlined in this 1802 patent gave increased power to steam engines. In early 1803 a second steam carriage of Trevithick's design was built at Camborne, and exhibited in London.

Later, in 1804, while employed as engineer at Pen-y-darran iron works near Merthyr Tydfil in Wales, Trevithick constructed the first steam locomotive to be used on rails . This marked the beginning of the age of the locomotive as we know it today.

Trevithick died in 1833 after a sudden illness.