Otto engine in a factory. 19th-century illustration of a gas engine (lower left) powering tissue presses in a paper factory. The connecting rod, belts and wheels across top transmit the power to the presses. The exhaust gases from the engine are being used to heat chemicals at lower centre. A gas engine is an internal combustion engine that runs on a gas fuel. The first practical gas engines included those by German engineer Nikolaus Otto (1832-1891) in the 1860s. Artwork from 'Moteurs' (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.