EXHIBIT

Advancement in Discovery

With the discovery of fission in the late 1930s, the cyclotron greatly advanced the project.  It consisted of the core components of an early particle accelerator (also known as an “atom smasher”).  Professor John R. Dunning and his team began construction of the cyclotron in 1936 in the basement of the Pupin Physics Laboratories building at Columbia University.  In order to achieve the highest possible voltage on the accelerating electrodes, team member Herbert L. Anderson developed the resonant concentric line feeding system which involves connecting the lines to a high-power oscillator.  The cyclotron was not complete in time to test the splitting of the uranium nucleus as initially discovered, but it was used to test the fission process by using a radioactive beryllium-radon mixture as the neutron to attack a uranium oxide target.  The test was successful and gave credibility to the new technology.

In March 1940, the cyclotron was used to show that the rarer uranium-235 isotope was a more successful fissile component than uranium-238.  The cyclotron was used until 1965 and the core components were subsequently donated to the Smithsonian Institution.  While many felt the cyclotron was not very significant, it did prove the validity of the discovery of fission which was key for the rest of the War.

Now that physicists were keenly aware of the concept of fission, the Manhattan Project itself could now begin.  As mentioned earlier, the production of uranium took place in Oak Ridge, Tennessee as well as in Hanford, Washington.  Pictured below is the K-25 plant, which was located at the southwestern end of the Oak Ridge site.  This plant used diffusion to separate uranium-235 from uranium-238 with the former being used in the atomic bombs.  The work at K-25 cost $500 million and 12,000 workers were employed.  The building was U-shaped and measured half a mile by 1,000 feet which is larger than the Pentagon.

A far less efficient plant named the S-50 Liquid Thermal Diffusion Plant was constructed next to the K-25 Plant.  The S-50 Plant used convection to separate isotopes into thousands of tall columns.  The S-50 Plant was taken down after the War, but the K-25 Plant was used for the design of other plants in Oak Ridge until it closed in 1987.  It has since been demolished due to environmental concerns.

The Manhattan Project was a secret mission from the general public.  Because of the secrecy of the Project, mail for the employees had to be sent to an undercover address in order to not raise questions about the ongoing work.  For the Los Alamos, New Mexico location of the Project, mail was sent to PO Box 1663, Santa Fe NM.  This system was set up by General Leslie Groves and Dr. J. Robert Oppenheimer when the site was chosen in November 1942.  The packages would be subsequently censored by a U.S. Army Examiner for security reasons.  This particular envelope is addressed to Staff Sargeant William Cody and was postmarked on May 1, 1944.  

The Manhattan Project was probably one of the most secure operations the federal government authorized.  So much so that President Roosevelt did not even tell his own Vice President Harry S. Truman about the Project.  When Truman became President in 1945, he only was made aware of the Project upon taking office and did not have much time to decide if the bombs should actually be used.  Truman would call the bomb “the most terrible bomb in the history of the world.”