REORGANIZATION AND ACCELERATION
Early Government Support, 1939-1942
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,
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.
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.
Sources and notes for this page.
The text for this page was adapted from,
and portions were taken directly from the Office of History and Heritage
Resources publications: F.
G. Gosling, The Manhattan Project: Making the Atomic Bomb
(DOE/MA-0001; Washington: History Division, Department of Energy, January
1999), 7-9, and Richard G. Hewlett and Oscar E. Anderson, Jr., The
New World, 1939-1946: Volume I, A History of the United States Atomic
Energy Commission (Washington: U.S. Atomic Energy Commission,
1972), 33-36. For more on the two National Academy of Sciences reports, see
Hewlett and Anderson, Jr., The New World, 1939-1946, 37, 39. The
photographs of Ernest
Lawrence, and of Vannevar Bush
Compton are courtesy the Lawrence
Berkeley National Laboratory. The mass spectrograph diagram is
reproduced from Gosling, The Manhattan Project, 7; the caption is
from Hewlett and Anderson, The New World, 1939-1946, 57.
Home | History
Office | OpenNet | DOE | Privacy and Security Notices
About this Site | How to Navigate this Site | Note on Sources |
Site Map | Contact Us