National Museum of Nuclear Science & History
McKinney worked in the 200 East Area at Hanford during the Manhattan Project.
G. Robert Gunther-Mohr joined the Manhattan Project in 1944. Mohr worked on the top secret polonium trigger being developed for the plutonium bomb at the Monsanto Chemical Company in Dayton, Ohio.
Harry S. Truman (1884-1972) was the 33rd President of the United States of America. Truman first learned of the Manhattan Project after the death of President Roosevelt in April of 1945, when he relinquished his role as Vice President and took the oath of office as the next president of the United States.