An unidentified woman and Edward Dorris McAlister (b. 1901) are shown working at the Smithsonian Institution's Division of Radiation and Organisms in Cambridge, Massachusetts. The apparatus shown was being used to measure the strength of ultraviolet radiation by killing algae. After earning a Ph.D. at University of California, Berkeley, in 1927, McAlister taught at the University of Oregon, 1927-1930, and then worked for the Smithsonian, 1930-1941. His specialty was infrared spectroscopy and instrumentation, and biophysics