From Treasury Vault to the Manhattan Project
The U.S. War Department borrowed 14,000 tons of government silver in its drive to make the world’s first atomic bomb
The U. S. Army’s World War II Manhattan Project was a drama unlike any other, with larger-than-life starring personalities, a supporting cast of more than 100,000, cutting-edge science, espionage and diplomatic intrigue. If that wasn’t enough, billions of dollars were gambled in the construction of enormous secret facilities to produce materials for a devastating weapon that might not work. All this played out against a background of worldwide conflict and the profound threat that Nazi Germany might achieve the world’s most powerful weapon first.
Any compelling drama includes subplots, and the Manhattan Project was no exception. While the main veins of the science, engineering, ethics and geopolitical implications surrounding the development of nuclear weapons have been well mined by historians, some aspects of the Manhattan Project have attracted less study. Over the past few years I have researched several, including the so-called Silver Program. The program was fundamental to finding a means to safely and quickly produce the tens of kilograms of uranium necessary for a weapon of mass destruction.
The secret government project to build the bomb was handed from the Office of Scientific Research and Development to the War Department in 1942. Management fell first to Colonel James C. Marshall of the Syracuse District of the U.S. Army Corps of Engineers. Marshall was ordered to establish a new district with no geographical boundaries. Its first offices were at the Atlantic Division headquarters on Broadway in New York City, hence the origin of the “Manhattan Engineer District” (MED), later called the Manhattan Project. Colonel (soon to be Brigadier General and later Major General) Leslie Groves was appointed commanding general of the new district in September 1942, a position senior to that of Marshall, who remained District Engineer until August 1943 when his deputy, Colonel Kenneth Nichols, replaced him.
The paramount problem for the MED was finding means to produce sufficient enriched uranium for an atomic bomb. By early 1942, only milligram-scale quantities of uranium-235 (235U) had been isolated and it was by no means clear if any of the laboratory methods in use then could be ramped up to an industrial scale. Research into several techniques was fast-tracked and three ultimately were used at Oak Ridge. (A fourth approach to securing fissile material, synthesis of plutonium, was used in giant reactors located in Hanford, Washington.) From the beginning, electromagnetic mass spectroscopy was identified as a promising method, and it quickly became clear to Marshall and Nichols that massive quantities of copper would be needed for the magnets’ windings. But copper—used in shell casings—was a high-priority commodity during the war. So Marshall and Nichols struck on the idea of using silver as a substitute. Congress had authorized the use of up to 86,000 tons of Treasury Department silver for defense purposes. Not having to divert mass amounts of copper was a huge boon for the project’s secrecy.
Nichols met with Undersecretary of the Treasury Daniel Bell on August 3, 1942, to inquire about borrowing 6,000 tons of silver from Treasury vaults. In his memoirs, Nichols relates that Bell indignantly informed him that the Treasury’s unit of measure was the troy ounce—though not all present at that meeting recall any unpleasantness. Many MED documents do report quantities of silver in troy ounces and fine troy ounces. At 480 grains, a troy ounce is somewhat heavier than a common avoirdupois ounce, which weighs in at 437.5 grains. Fine troy ounces (FTOs) refer to the purity of the bullion: a 1,000 troy ounce “silver” bar of fineness 0.900 contains 900 FTOs of pure silver. For convenience, I quote weights in pounds of metal here after accounting for fineness.
It is not uncommon to read Groves described as arrogant, arbitrary, insensitive, overbearing and high-handed. More appropriate labels might be mission focused and supremely competent. Groves graduated fourth in his 1918 West Point class and also trained at the Army Engineer School, the Command and General Staff School and the Army War College. His career in the Corps of Engineers was marked by steady advancement. When he assumed command of the MED, he was deputy chief of construction of the Corps of Engineers and was responsible for all domestic military construction. He had just overseen the building of the Pentagon and was well versed in the capabilities of large-scale contractors. It was Groves who selected J. Robert Oppenheimer to be the scientific director of the Los Alamos Laboratory, where the bomb was designed and built. The biographer Robert Norris described Groves as the project’s “Indispensable Man.” In Nichols’s blunter words: “General Groves is the biggest S.O.B. I have ever worked for. He is most demanding. He is most critical.… He is abrasive and sarcastic.… He is extremely intelligent … abounds with energy … if I had to do my part of the atomic bomb project over again and had the privilege of picking my boss I would pick General Groves.”