Smithsonian Institution Building (Washington, D.C.) Search this
Smithsonian Astrophysical Observatory Radiation and Organisms Division Search this
Century of Progress International Exposition (1933-1934 : Chicago, Ill.) Search this
4 x 3.25;
Between 1929 and 1934
See also MNH-11036D.
Dr. Earl S. Johnston in the research laboratory of the Division of Radiation and Organisms, located in the basement of the Smithsonian Institution Building, or Castle. Effects of light on plant growth are studied here.