Potter improving Newcomen engine. Illustration of the claim that in 1713 a boy named Humphrey Potter invented the self-acting mechanism for the Newcomen engine. A system of ropes and pulleys are shown being used by the boy, whose job it was to open and shut the valves of the engine. The Newcomen atmospheric (Thomas Newcomen, 1712) was the first true steam engine. The cords shown here were known as 'potter cords'. Artwork from 'Chaudieres et Machines a Vapeur' (1911) by French civil engineer Max de Nansouty (1854-1913), part of the 'Les merveilles de la science' series of 1867-1891 by Louis Figuier.