National Museum of Nuclear Science & History
Roger M. Smith served in the First Ordnance Squadron.
Hugo Leckelt was a laborer at the University of Chicago’s Metallurgical Laboratory (“Met Lab”) during the Manhattan Project.
Hayes worked in the United States Engineer District Office.
George Cowan joined the Manhattan Project in 1942 at the Met Lab as a chemist for Enrico Fermi’s group, and also worked for Columbia University.
