From Wiki:
Nikolaus August Otto: 1832-1891. As a young man, Otto was a traveling salesman for a grocery concern. In his travels he encountered the internal combustion engine built in Paris by Belgian expatriate Jean Joseph Etienne Lenoir. In 1860 Lenoir succeeded in creating a double-acting (think: 2 cycle) engine which ran on illuminating gas at 4% efficiency. The 18 liter Lenoir engine was able to produce only 2 horsepower.
In testing a replica of the Lenoir engine in 1861 Otto became aware of the effects of compression on the fuel charge. In 1862 Otto attempted to produce an engine to improve on the poor efficiency and reliability of the Lenoir engine. He tried to create an engine which would compress the fuel mixture prior to ignition, but failed, as that engine would run no more than a few minutes prior to its destruction. Many engineers were also trying to solve the problem with no success.
By 1876 Otto (and Langen) succeeded in creating the first internal combustion engine that compressed the fuel mixture prior to combustion for far higher efficiency than any engine created to this time.
The "Otto cycle" is another name for, or rather describes the idealized thermodynamic properties (pressure, volume, temperature, entropy, etc..) of, the 4 cycles of a 4 cycle internal combustion engine.
It seems few Americans know the history of something as world changing as the gasoline engine. Could it be because it wasn't invented in America?
But ask them who (invented) the car or the light bulb and they'd probably tell you Henry Ford and Thomas Edison!
