Jacques Francais died in Metz, France. He wrote an article that helped popularize the geometric representation of complex numbers proposed by Wessel and Argand (MacTutor History of Mathematics Archive).
Howard Aiken born in Hoboken, New Jersey. He developed and built the ASCC computer (Automatic Sequence Controlled Calculator), which he viewed as the fruition of Charles Babbage's plans for his "analytic engine," completing construction in 1943. Grace Hopper joined his development team in 1944.