**Jean Baptiste Joseph Fourier**, were born on March 21, 1768, and died on May 16, 1830. He was a French mathematician known primarily for his contribution to the mathematical analysis of heat flow. Trained for the priesthood, Fourier did not make his vows. Instead, he headed toward mathematics. He first studied (1794) and then taught mathematics at the newly created Normal School. He joined (1798) Napoleon's army in his invasion of Egypt as a scientific advisor to help establish educational facilities there and undertake archaeological explorations.

After his return to France in 1801 he was appointed mayor of the department of Isere by Napoleon.

Throughout his life Fourier has shown his interest in mathematics and mathematical physics. He was famous for his *Theorie analytique de la Chaleur* (1822), a mathematical treatment of heat theory. He established the partial differential equation by managing heat diffusion and solved it using an infinite series of trigonometric functions. Although these series have been used before, Fourier has investigated them in much greater detail. His research, initially criticized for its lack of rigor, was later shown to be valid. It provided the impetus for the latest work on trigonometric series and the theory of functions of a real variable.

Bell, Eric T., Men of Mathematics (1937; repr. 1986); Grattan-Guinness, Ivor, Joseph Fourier (1972); Herivel, John, Joseph Fourier: The Man and the Physicist (1975)