By David C. Cassidy

At St. Louis, seven speakers enlightened a standing-room only audience on a wide range of topics surrounding “The Manhattan Project and Beyond.”

Project veteran E. Leonard Jossem opened the session with “Remembering Los Alamos.” He arrived there in July 1945 and began work in the Experimental Physics (P) Division, designing and constructing specialized equipment. He later switched to F-Division where he worked on the “Super” or H-bomb. Jossem was a founding member of the Association of Los Alamos Scientists, which sought to prevent future wars through the international control of nuclear weapons. Among the ALAS initiatives was a packet sent to the mayors of major US cities containing a letter and a piece of fused sand from Alamogordo as a warning of what could happen to their cities in a nuclear war. An important success of the scientists’ movement was the achievement of civilian control of nuclear energy under the Atomic Energy Commission.

Harry Lustig (City University of NY, emeritus), addressed the question “Did the Allies Know in 1942 about Nazi Germany’s Poor Prospects for an Atomic Bomb?” The probable answer is that British intelligence knew about these prospects “well before 1945” but did not inform their US counterparts until very late. According to Arnold Kramish, in The Griffin (1986), German physicist Paul Rosbaud informed the British that the German effort had “ground to a halt” in 1942, but it is not firmly known when he delivered his report. British Scientific Intelligence officer R. V. Jones allowed that his agency was convinced of this fact by 1943. Because the official information about Rosbaud’s work is still buried in secret British and American files, Kramish had to base his account on largely undocumented sources. General Leslie Groves was not briefed on the German status until May 1944 but refused to believe it. By then the project could not be stopped, nor probably could it have been in 1943. The full truth of what happened will not be known unless and until the Rosbaud files are declassified. (Editor’s Note: See Lustig’s letter on this subject.)

Christine Hampton spoke on “Revisiting the 100-Year-Old Radioactivity Lectures of Frederick Soddy.” In 1908 nuclear researcher Soddy (Nobel Prize in Chemistry, 1921) gave six experimental lectures at the University of Glasgow for his wealthy patrons and the general public. They were published a year later as The Interpretation of Radium. Since many academics still doubted the existence of atoms, Soddy in these lectures showed that “radium emanation” (radon), which is produced by a series of decays, not only exists but is a true, compressible gas, even though it could not be weighed by standard balances of the day. Soddy also foresaw the potential dangers of the energy released in radioactivity. In 1908 he wrote that it would become a question “of life and death to the inheritors of our civilization.” Among the original group of radioactivity researchers, Soddy was the only one to witness the effects of the Manhattan Project and its aftermath.

Cameron Reed (Alma College) examined “Arthur Compton’s 1941 Analysis of Explosive Fission in U-235: The Physics.” Compton’s analysis did not mention the British MAUD Report, which covered the same ground; it may be seen as a precursor to Robert Serber’s later Primer. Compton’s calculation of the critical radius was quite accurate, but that for the critical mass was roughly half the actual value. Neglecting the dependence on initial conditions, his results for the time of core expansion to non-criticality for a bomb of two critical masses of fissile material was very close to the modern value, but the calculated efficiency of 1.4 percent was far short of the modern value of 5.4 percent. Since most of the calculations were not especially difficult and are at the level of undergraduate physics today, one wonders why Heisenberg fumbled them at Farm Hall in his calculation there, and perhaps earlier. Reed’s full paper on Compton’s analysis was published in the December 2007 issue of American Journal of Physics.

Samuel Fletcher (Princeton IUniversity), recipient of the Maria Goeppert-Mayer Studentship, spoke on “The Manhattan Project and Its Effects on American Women Scientists.” Like most histories, Manhattan Project histories have been concerned with only the leading scientists, who were in most cases men. Not until Ruth Howes and Caroline Herzenberg wrote Their Day in the Sun (1999) have the contributions of many of the women scientists to the Project been described. Women made up about 30 percent of the scientific and technical staff. Yet a comparison of salaries and other aspects of their lives and work indicated that cultural values about women in science did not change, although they were accorded sufficient support in their work. As in other areas of the economy, they were regarded as substitutes for men, and many lost their jobs as soon as the wartime labor shortage ended. This study suggests that significant social change is not possible without change in the culture at large (Editor’s note: See also the related article by Virginia Trimble and George Zimmerman.)

Matthew Geramita (University of Michigan) then spoke on “X-Ray Spectroscopy, the Ellen Richards Prize, and Nuclear Proliferation: The Inspiring Life of Katherine Chamberlain.” Chamberlain earned her doctorate at the University of Michigan and continued work there with George Lindsay on X-ray spectroscopy during the 1920s. When she explained a secondary absorption line observed by Dirk Coster, she was awarded the Richards Prize for outstanding young women scientists, which enabled her to work with J. J. Thomson at the Cavendish Laboratory. Returning to the States, she taught photography at Wayne State University in Detroit and wrote a widely read textbook on the subject. The atomic bomb inspired her support of efforts to control nuclear weapons through the popular movement for a world government. Despite the failure of that movement as the Cold War deepened, she remained undeterred in the effort to control these weapons.

Michael Friedlander (Washington University, St. Louis) took the audience “From Alamogordo to the Nuclear Test-Ban Treaty.” As nuclear weapons testing continued during the years following Alamogordo, and with attention being drawn to the spread of radioactive fallout by Adlai Stevenson’s 1956 presidential campaign, the Greater St. Louis Citizens Committee for Nuclear Information was formed in March 1958. It pursued an active campaign to educate the public on nuclear radiation and on the dangers of fallout. Linus Pauling’s petition plus Committee lectures, press information, and Congressional testimony helped to bring about the Limited Test-Ban Treaty of 1963, which may be regarded as the direct result of public concern over fallout. Likewise, criticism by the Committee and Alaskan scientists of the plan to excavate an Alaskan harbor using nuclear explosions inspired public opposition and led to cancellation of the plan. These examples demonstrate that scientists’ warnings can have public impact when the scientists stick to the facts and to their expertise, especially when they translate their technical knowledge of a problem into terms the general public can readily understand.