National Museum of Nuclear Science & History
H. L. Shaefer worked for the Edenfield Electric Company.
Arthur Harold Jaffey was an associate chemist at the University of Chicago’s Metallurgical Laboratory (“Met Lab”) during the Manhattan Project.
George Mallinckrodt was a physicist at the Manhattan Project’s Los Alamos, NM facility. He also worked at Argonne National Laboratory, the successor of the University of Chicago’s Metallurgical Laboratory (“Met Lab”).
