Dieter Gruen joined the Manhattan Project at Oak Ridge in September of 1944, shortly after his graduation from Northwestern University. His work primarily focused on the chemical problems related to the separation of uranium isotopes. In response to difficulties determining the difference between uranium nitrate and uranium peroxide in the final stages of separation, Gruen created an entirely new material: sulfonated copper phthalocyanine. This indicator maintained stability in nitric acid, allowing for the easy identification and eventual extraction of uranium nitrate. Immediately after the war, he helped form Oak Ridge Scientists and Engineers, a group dedicated to ensuring the future prevention of the use of nuclear weapons in war. In this interview, Gruen discusses the secrecy related to the project, the relatively lax safety standards of the period, and the differences between government support for science in the 1950s and government support today.
Lew Kowarski was a Russian-born French physicist who worked as part of the team that discovered that neutrons were emitted in the fission of uranium-235 in the 1930s, setting the groundwork for the use of nuclear chain reactions in the design of the atomic bomb. After the Second World War, Kowarski went on to supervise the first French nuclear reactors and became a staff member of the European Organization for Nuclear Research, or CERN, in 1953. In this interview Kowarski discusses his upbringing in Russia, and the beginnings of his scientific career under Frédéric Joliot-Curie. He also outlines the process through which the splitting of uranium atoms was realized.
Richard Yalman was a member of the Special Engineer Detachment and worked on polonium separation at the top-secret laboratories in Dayton, Ohio during the Manhattan Project. In this interview, Yalman discusses his undergraduate work at Harvard University and how he came to be involved on the Manhattan Project. He elaborates on the degree of secrecy within the project location, stressing the separation of the four units at Dayton and how no one talked about their work. Yalman also describes his personal life, the scientists he worked with, how he met his wife, and his work after the war.
Eugene Wigner was a Hungarian-American theoretical physicist and mathematician and 1963 Nobel Prize winner in Physics. During the Manhattan Project, Wigner led a group responsible for the design of Hanford’s B Reactor. In this interview, Wigner discusses his upbringing and education. He elaborates on his involvement with the Einstein Letter, which Einstein sent to President Franklin Roosevelt urging he begin research into an atomic bomb and led to the Manhattan Project research. Einstein dictated the letter to Wigner, and Wigner was very impressed by Einstein’s ability to dictate such an important letter so quickly. Wigner also elaborates on the personalities of Leo Szilard, Enrico Fermi, and other scientists.
John Mench was assigned to the Special Engineer Detachment at Los Alamos where he worked as a pattern maker, creating wooden casts for metal work at the site’s foundry. Mench describes what it was like to live in the barracks at Los Alamos and discusses everything from housing and recreation to security and secrecy, including his daughter’s birth certificate, which was marked P.O. Box 1663. Mench also discusses the founding of the Los Alamos Little Theater, where he directed numerous plays that were attended by some of the most famous scientists on the site. He jokingly recounts a date with one of the young WACs, who never invited him to dinner again because he spent the entire date talking about his wife and child. On a more serious note, Mench offers his opinion on the use of the atomic bomb against Japan and the importance of the Manhattan Project in ending the war.
Seth Wheatley worked on the Beta calutrons at the Y-12 plant in Oak Ridge during the Manhattan Project. He talks about African-American segregation, an often forgotten aspect of life in the city during the project. He discusses worker safety at Y-12 and raising a baby in the secret city of Oak Ridge.
Nancy Bartlit is the former president of the Los Alamos Historical Society and co-author of Silent Voices of World War II: When Sons of the Land of Enchantment Met Sons of the Land of the Rising Sun. Her father worked on the Manhattan Project in New York City, Oak Ridge, and Canada. Bartlit talks about how her experiences teaching at a girls’ school in Japan and living in Los Alamos influenced her work as a historian. She discusses Japan’s surrender, the internment of Japanese Americans, Navajo Code Talkers, and how Japan remembers the bombings today.
In this segment, Groves discusses the establishment of the project sites at Los Alamos and Hanford. He talks about the role Oppenheimer had in influencing the choice of the Los Alamos site, and the planning that went into ensuring the site was both accessible but would not draw attention. In regards to Hanford, he talks about the innovative efforts to gauge water pollution and protect the salmon in and around the Columbia River.
Freeman Dyson is an esteemed mathematician and theoretical physicist at Princeton’s Institute for Advanced Study. In this interview, Dyson discusses his work at England’s Bomber Command in World War II, tracking the position of bomber forces. He explains the importance of scientific innovation in wartime, the effectiveness of strategic bombing campaigns, and why civil defense worked better in Germany than in Britain. Dyson later worked with Manhattan Project veterans Hans Bethe, Richard Feynman, and Robert R. Wilson, and recalls how they felt about the project. He discusses Niels Bohr and J. Robert Oppenheimer’s ideas for international control of nuclear weapons, and what methods he thinks would work best to further nonproliferation efforts today. Dyson also remembers visiting Oak Ridge, and explains Oak Ridge’s important role in building innovative nuclear reactors and conducting biological experiments.
Tom Gary was a military engineer during World War II. In his interview, he discusses how he began working at the age of nineteen, dropping out of high school just two months before graduation to support his family. He worked on the railroads for a decade before applying to become an Army first lieutenant. After earning the position, he was deployed to France, and sent back to the United States following the end of the war. He then became the head of design for DuPont. Gary also helped design the plants at Hanford and Oak Ridge.