Before then, the steam engine was the power plant of choice. By 1770, the steam engine had been developed to the point that the French engineer Nicolas Cugnot used one to successfully propel a three-wheeled vehicle, and steam power reigned supreme in industry for nearly a century.
Early in the industrial revolution, inventors struggled to develop an engine in which compressed fuel could be burned within a cylinder housing a piston, thus capturing a much greater amount of the potential energy of the fuel. French physicist Nicholas Carnot (1796-1832) published a book in 1824 in which he set out the principles of an internal combustion engine which would use a flammable mixture of gas vapor and air. Basing his work on Carnot's principles, another Frenchman, Jean-Joseph-Éttien Lenoir, presented the world with its first workable internal combustion engine in 1859. Lenoir's motor was a two-cycle, one-cylinder engine with slide valves and used illuminating gas (coal gas) as a fuel; it also used an electrical charge, supplied by a battery, to ignite the gas after it was drawn into the cylinder. Lenoir sold several hundred of his engines, and he adapted his engine to power a carriage; consequently, he is credited with inventing the first gas-powered automobile. Lenoir's primitive two-stroke design, however, was inefficient because each back-and-forth motion of the piston must draw