National Museum of Nuclear Science & History
Melvin A. Miller was a draftsman at the University of Chicago Met Lab. In 1946, he sketched two famous drawings of Chicago Pile-1 based on the descriptions of scientists who were present when it went critical.
Karl Walther was a glassblower for Columbia University and Brookhaven National Laboratory. During the Manhattan Project, Walther worked as a senior glassblower at the Nash Garage Building at Columbia, where scientists developed the gaseous diffusion process.
Marion L. Arnold was a staff member at Los Alamos during the Manhattan Project.