Ludwig Boltzmann, an Austrian theoretical physicist, was born and educated in Vienna. Boltzmann moved from post to post throughout Europe and visited the United States three times. Independent of the pioneering research of James Clerk Maxwell, Boltzmann developed the kinetic theory of gases. He also established a firm theoretical foundation for statistical mechanics by successfully interpreting the second law of thermodynamics in terms of order and disorder. Using thermodynamics, he derived the law governing the radiation rate of a black body. In the late nineteenth century, Boltzmann championed the controversial subject of the atomic theory of matter. As a result of serious depression… caused by these bitter professional debates, he committed suicide in 1906. Ironically, this happened just before the last of his opponents finally accepted the atomic theory. Boltzmann's famous equation, SklogW, which relates the entropy S of a system to its probability W, is engraved on his tombstone. Boltzmann died in 1906.