Engines

As early as 1759, hot air was proposed as a substitute for the steam-power piston machine, but the first working model was not built until 1807. Robert Stirling in England and John Ericsson in America sold hot air machines to the public in the late 19th century. It was not until about 1900 that the hot air engine was supplanted with another variant upon the steam-piston machine -- internal combustion within the cylinder. In 1791, an internal combustion engine was patented in England, running on vaporized turpentine. However, the first production model of an internal combustion engine fueled by illuminating gas was designed by Belgium inventor Jean Joseph Etienne Lenoir in 1860. A Frenchman, Alphonse Beau de Roches, dealt later with the means of refining Lenoir's machine the running costs of which had been excessive. However, it was a self-educated German mechanic Nikolaus Otto who developed the four-stroke gas engine that compressed the fuel vapor in the cylinder before uniting it. The gas engines were not only lighter and faster-starting than the steam type but used petroleum as a power source.