National Museum of Nuclear Science & History
Robert Ball was a security guard at the Metallurgical Laboratory in Chicago during the Manhattan Project.
Luin W. Hough was a photographer at the University of Chicago’s Metallurgical Laboratory (“Met Lab”) during the Manhattan Project.
E. G. Richardson worked for the Tennessee Eastman Corporation at the Y-12 Plant.
Fredrick “Fred” D. Johnson was a research assistant at the University of Chicago’s Metallurgical Laboratory (“Met Lab”) during the Manhattan Project.