REORGANIZATION AND ACCELERATION
(1940-1941)
Events: Early Government
Support, 1939-1942
During 1939 and 1940, most of the work done on uranium
isotope separation and the chain reaction
pile was performed in university laboratories by academic scientists funded
primarily by private foundations. Although the federal government began
supporting uranium research in 1940, the pace appeared too leisurely to the
scientific community and failed to convince scientists that their work was of
high priority. Certainly few were more inclined to this view than Ernest
O. Lawrence (right), director of the Radiation Laboratory at the University of California,
Berkeley. Lawrence
was among those who thought that it was merely a matter of time before the
United States was drawn into World War II, and he wanted the government to
mobilize its scientific forces as rapidly as possible.
Early in 1941, Lawrence began to toy with another idea, using the electromagnetic method to separate the
uranium-235 isotope, which made action seem all the more important. He proposed
converting his smaller, thirty-seven-inch cyclotron into a super mass
spectrograph to produce uranium-235. Alfred O. C. Nier of the University of Minnesota had been using a mass spectrometer
(spectrograph) to prepare small samples of partially separated uranium-235. The
mass spectrograph depended on the principle that the lighter particles,
uranium-235, in a high-speed beam of ions –- positively charged particles –-
were deflected to a greater degree than the heavier ones, uranium-238, as they
passed through a magnetic field. Since both Lawrence’s cyclotron and the spectrograph used a
vacuum chamber and electromagnet, conversion from one to the other would be
relatively uncomplicated. (He later named the result a "calutron.") Lawrence thought that this would open the way to separate
larger, purer samples of uranium-235 for study and, eventually, to derive the
lighter isotope on a large scale.
Lawrence, demonstrating his characteristic energy and impatience, launched a
campaign to speed up uranium research. Lawrence took his case to Karl
T. Compton and Alfred L. Loomis at Harvard University, both doing radar
work for the National Defense Research Committee and benefiting from Lawrence's advice in staffing
their laboratories. Infected by Lawrence's enthusiasm, Compton forwarded Lawrence's optimistic
assessment on uranium research to Vannevar Bush, warning that Germany was undoubtedly
making progress and that Lyman J. Briggs and the uranium committee were
moving too slowly. Compton also noted that the
British were ahead of their American colleagues, even though, in his opinion,
they were inferior in both numbers and ability.
Bush and Lawrence met in New York City. Though he continued to support
the Uranium Committee, Bush recognized that Lawrence's assessment was not far
off the mark. Bush shrewdly decided to appoint Lawrence as an advisor to
Briggs -- a move that quickly resulted in funding for plutonium work at Berkeley
and for Alfred Nier's mass spectrograph at Minnesota -- and also asked the
National Academy of Sciences to review the uranium research program.
Headed by Arthur Compton of the University
of Chicago and including Lawrence, this committee submitted its
unanimous report on May 17, 1941. Compton's committee, however, failed to
provide the practical-minded Bush with the evidence he needed that uranium
research would pay off in the event the United States went to war in the near
future. Compton's group thought that increased uranium funding could
produce radioactive material that could be dropped on an enemy by 1943, a pile
that could power naval vessels in three or four years, and a bomb of enormous
power at an indeterminate point, but certainly not before 1945. Compton's
report discussed bomb production only in connection with slow
neutrons, a clear
indication that much more scientific work remained to be done before an
explosive device could be detonated.
Bush reconstituted the National Academy of Sciences committee and instructed
it to assess the recommendations contained in the first report from an
engineering standpoint. On July 11, the second committee endorsed the first
report and supported continuation of isotope separation work and pile research
for scientific reasons, though it admitted that it could promise no immediate
applications. The second report, like the first, was a disappointing
document from Bush's point of view.
By the time Bush received the second National Academy of Sciences
report, he had assumed the position of director of the newly-created Office
of Scientific Research and Development (OSRD). The Uranium
Committee became the OSRD Section on Uranium and was codenamed S-1. The
National Defense Research Committee, now headed by James B. Conant, president
of Harvard University, became an advisory
body responsible for making research and development recommendations to the
OSRD.

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