The Field Museum is one of the world's leading natural history museums. Founded as the Columbian Museum of Chicago in 1893, the institution adopted the Field name in 1905 in honor of major benefactor (and department store mogul) Marshall Field. The museum houses enormous biological and anthropological collections -- more than 24 million specimens in all -- along with a quarter-million-volume natural history library. It is also home to Sue, the largest, most complete, and best preserved Tyrannosaurus rex fossil discovered to date. The Field Museum conducts basic research in anthropology and biology, as well as an extensive program of public education.