Nikolaus August Otto (1832-1891) was born in Holzhausen, Germany. As a young man he developed an interest in mechanical engineering and began experimenting with making gas engines. In 1867 he developed his first atmospheric engine. Then, in 1876, together with Eugen Langen (1833-1895), he pioneered the four-stroke internal combustion engine. However, Otto's patent was invalidated in 1886 when it was discovered that another inventor, the Frenchman Alphonse Beau de Rochas (1815-1845), had described the four-stroke cycle principle in an earlier published paper.
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