Herbert Anderson was completing his graduate studies in physics in 1939 at Columbia University when he began a close scientific and personal association with Enrico Fermi that was to continue until Fermi's death in 1954. Anderson assisted Fermi in early research on nuclear fission, including Fermi's direction of the first chain reaction. Anderson himself early in 1939 at Columbia, performed the experiment which resulted in the first observation of fission in the United States.
William E. Tewes worked on the gaseous diffusion process at the Nash Garage Building under Dr. Francis Slack, testing the barrier material. He recalls the Nazi invasion of Poland and how the attack on Pearl Harbor brought the country together. In July 1945 Tewes was transferred from New York, where he was working on gaseous diffusion, to Oak Ridge. He worked on the leak testing operation at K-25.