National Museum of Nuclear Science & History
J. N. Holt worked for the United States Engineer District Office.
Bob Emigh was in the Navy and worked with Deak Parsons on telemetry for the bombs. He was assigned as the science officer for the planned third bomb.
Ernest Morgan worked for the J.A. Jones Construction Company.
William Karush (1917-1997) was an American mathematician and physicist. After earning his Ph.D. from the University of Chicago in 1942, Karush worked briefly at the Carnegie Institution of Washington before returning to Chicago to join the Manhattan Project.
C. J. Toney worked for the Tennessee Eastman Corporation at the Y-12 Plant.