 In the early years of World War II between 1939 and 1941 , Wigner led the Princeton group in a series of experiments involving uranium and two tons of graphite as a neutron <unk> . In early 1942 , Arthur Compton concentrated the Manhattan Project 's various teams working on plutonium and nuclear reactor design , including Wigner 's team from Princeton , at the Metallurgical Laboratory at the University of Chicago . The name was a <unk> ; Creutz was the first to conduct actual metallurgy research , and he hired its first <unk> to work with him . 
