Family background, education, and emergence of scientific orientation. Undergraduate years at Wellesley College (1912-1916); description of physics department. Assistant examiner in U.S. Patent Office during World War I. At MIT under E.B. Wilson as graduate student and laboratory assistant, then lab instructor (1920-24). Returned to MIT for doctoral work in 1928. Mathematical physics thesis under Norbert Wiener, while teaching at Wellesley. Depression years brought teaching position at Wilson College (1930-43), used Wellesley as model. Work on Zeeman Pattern earns her Guggenheim Fellowship (1949-50) at MIT and European labs. World War II years as head of OSRD British Report Section. Returned to Wilson (1945-56), worked part-time at National Science Foundation (1953-56). Retirement years including affiliation with U.S. Army and spectroscopic work at Harvard College Observatory. Comments on women in physics in U.S., her own opportunities, and teaching in general.