National Museum of Nuclear Science & History
R. J. Guthrie worked for the Watson-Flagg Engineering Company.
Arthur Harold Jaffey was an associate chemist at the University of Chicago’s Metallurgical Laboratory (“Met Lab”) during the Manhattan Project.
H.A. Fettinger was a junior physicist at the University of Chicago’s Metallurgical Laboratory (“Met Lab”) during the Manhattan Project.
J. M. Ryan worked for the United States Engineer District Office.
