Oral Histories

Dr. Alfred Nier was an American physicist well-known for his work on spectrometry. Nier designed the mass spectrometers used for Manhattan Project experiments and his instruments were sent to all of the major Project sites. With his mass spectrometer, Nier helped prove that that U-235 was fissile, not the more abundant isotope U-238. Nier worked for the Kellex Corporation to design and construct the apparatuses used to monitor the separation of Uranium-235 and Uranium-238, as well as leak detectors for the K-25 gaseous diffusion plant. In this interview, Nier discusses his early involvement in the Manhattan Project in New York and the transport of uranium between Project sites. He also discusses his experiences working at both the Nash Garage Building in New York City, and the K-25 Plant at Oak Ridge, Tennessee.

Arthur Squires was a chemical engineer and participated in the design, construction, and operation of the K-25 diffusion plant at Oak Ridge, Tennessee. Squires describes the lead developer, Percival Keith, as well as Manson Benedict, both of whom he credits as key contributors to the plant’s development. Squires discusses the impact of the K-25 plant, saying that without its development, it is likely that two atomic bombs would not have been ready into at least mid-1946. He also highlights the level of secrecy surrounding the work on the Manhattan Project. In 1946, Squires went on to work with Keith’s new company, Hydrocarbon Research.

Arthur Squires was born in Kansas and received a Bachelor’s Degree in Chemistry from the University of Missouri, and went on to Cornell University for his graduate degree. He was a chemical engineer and participated in the design, construction, and operation of the K-25 diffusion plant at Oak Ridge, Tennessee, working under Percival Keith and Manson Benedict. In this interview, Squires recounts how he contributed to the scientific research and problem-solving that helped make the K-25 plant possible. In the discussion, Stephane Groueff asks Squires about his relationships with the other scientists, developers, and academic teams.

John Arnold joined the Manhattan Project in 1943 when the MED tasked his employer, the Kellogg Corporation, with developing a special barrier for the gaseous diffusion plant in Oak Ridge. Arnold discusses his role as director of research and development and process engineering at the plant, where he supervised the assembly and testing of what would become the K-25 plant. In his interview, Arnold describes the challenges of creating a suitable barrier that could withstand the corrosive effects of uranium hexafluoride gas while remaining porous enough to allow smaller atoms of uranium-235 to pass through.

Percival Keith was the head of the Kellex Corporation. In his interview, he discusses the recruitment of top scientists and engineers, including George Watts, Manson Benedict, and Ludwig Skog. He was tasked with constructing the gaseous diffusion plant for uranium isotope separation. Keith focuses on the decision to abandon the flat barrier design for the tube model, and how doing so was instrumental in finishing the project.

John Shacter was born in Austria and immigrated to the United States after Hitler came to power in Germany. He first worked on the Manhattan Project at Columbia University, then was transferred to the K-25 Plant in Oak Ridge in 1943. He explains how the innovative design of the uranium enrichment process facilitated the design and construction of nuclear reactors around the country. He recalls the urgency the workers felt to beat Nazi Germany in making an atomic bomb.