The Priestley Medal is the highest honor conferred by the American Chemical Society (ACS) and is awarded for distinguished service in the field of chemistry. Established in 1922, the award is named after Joseph Priestley, the discoverer of oxygen who immigrated to the United States of America in 1794. The ACS formed in 1876, spearheaded by a group of chemists who had met two years previously in Priestley's home. The Priestley Medal is commonly awarded to scientists who are advanced in their fields, as it is intended to commemorate lifetime achievement. When the ACS started presenting the Priestley Medal in 1923, they intended to award it every three years. This continued until 1944, when it became an annual award. Recipients 1920s 1923 Ira Remsen 1926 Edgar Fahs Smith 1929 Francis P. Garvan 1930s 1932 Charles L. Parsons 1935 William A. Noyes 1938 Marston T. Bogert 1940s 1941 Thomas Midgley, Jr. 1944 James Bryant Conant 1945 Ian Heilbron 1946 Roger Adams 1947 Warren K. Lewis 1948 Edward R. Weidlein 1949 Arthur B. Lamb 1950s 1950 Charles A. Kraus 1951 E. J. Crane 1952 Samuel C. Lind 1953 Sir Robert Robinson 1954 W. Albert Noyes, Jr. (son of William A. Noyes) 1955 Charles A. Thomas 1956 Carl S. Marvel 1957 Farrington Daniels 1958 Ernest H. Volwiler 1959 Hermann Irving Schlesinger 1960s 1960 Wallace R. Brode 1961 Louis Plack Hammett 1962 Joel H. Hildebrand 1963 Peter J. W. Debye 1964 John C. Bailar, Jr. 1965 William J. Sparks 1966 William O. Baker 1967 Ralph Connor 1968 William G. Young 1969 Kenneth S. Pitzer 1970s 1970 Max Tishler 1971 Frederick D. Rossini 1972 George B. Kistiakowsky 1973 Harold C. Urey 1974 Paul J. Flory 1975 Henry Eyring 1976 George S. Hammond 1977 Henry Gilman 1978 Melvin Calvin 1979 Glenn T. Seaborg 1980s 1980 Milton Harris 1981 Herbert C. Brown 1982 Bryce Crawford, Jr. 1983 Robert S. Mulliken 1984 Linus Pauling 1985 Henry Taube 1986 Karl A. Folkers 1987 John D. Roberts 1988 Frank H. Westheimer 1989 George C. Pimentel 1990s 1990 Roald Hoffmann 1991 Harry B. Gray 1992 Carl Djerassi 1993 Robert W. Parry 1994 Howard E. Simmons 1995 Sir Derek H. R. Barton 1996 Ernest L. Eliel 1997 Mary L. Good 1998 F. Albert Cotton 1999 Ronald Breslow 2000s 2000 Darleane C. Hoffman 2001 Fred Basolo 2002 Allen J. Bard 2003 Edwin J. Vandenberg 2004 Elias J. Corey 2005 George A. Olah 2006