In 50 BC, Heron of Greece suggested the used of steam power. The leaders of the day thought that it would cause unemployment which may lead to unrest and the invention ran out of steam. Steam technology known to the Chinese by 800 BC. Plato, in his Hero of Alexandria of 150 BC, mentioned some 70 steam inventions. But the steam engine reappeared again only in 1698 when Thomas Savery invented a steam pump. The first practical steam engine was the atmospheric machine of Thomas Newcomen in 1701. It was used to operate pumps on coal mines. In 1769, Nicolas Joseph Cugnot drove his steam tractor, officially the first known motorcar, down a street in Paris. In 1804, English inventor Richard Trevithick introduced the steam locomotive in Wales. In 1815, George Stephenson built the world’s first workable steam locomotive. Imagine how much further developments would have been had Heron’s steam power theory been put in practice in 50 BC.