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To Fermi ~ with Love – Part 2

Laura Fermi discusses the family’s decision to leave Italy in 1938 in the wake of the government’s support for anti-Semitic laws. The program describes Enrico winning the Nobel Prize for Physics. Herb Anderson, Fermi’s associate at Columbia University in New York, remembers Fermi’s arrival to the city and move to Chicago to work in the Chicago Met Lab. Fermi explains how scientists agreed to keep the Manhattan Project secret. The interviewees also recall working on the Chicago Pile-1. Anderson, George Weil, and others also describe Fermi’s most distinctive qualities: his energy, willingness to collaborate, and informal approach.

Date of Interview:
September 12, 1971
Location of the Interview:


[Thanks to Ronald K. Smeltzer for donating the record “To Fermi with Love” to the Atomic Heritage Foundation.]

Narrator: It was a major emotional decision for Mrs. Fermi, causing her great pain. She had been born in Rome, always lived there. Her relatives and friends were there. She felt she belonged to Rome, but in May of 1938, Hitler visited Italy as a guest of Mussolini and the die was cast. Once the racial and other restrictive laws were passed in early September, the Italians emigrating to the United States increased rapidly. It was time to make plans. Fermi had already received five offers to come to America. Mrs. Fermi remembers. 

Laura Fermi: We planned several times to come. As a matter of fact, at the Institute for Advanced Study [in Princeton, New Jersey] there was a physicist who was called Fermi’s assistant. Of course, we never were there, Enrico was never there, but he had accepted the position on condition that he would have an assistant, so the assistant was there.

Narrator: The collaboration of Italian physics was fast coming to an end. The Corbino group was being dissolved by uncontrollable forces. Professor Corbino had died of pneumonia in January 1937 at the age of sixty-seven. [Emilio] Segrè, in Palermo since 1936, remained permanently at the University of California following a summer session there. [Franco] Rasetti would leave Italy in June of 1939 to become Professor of Physics at Laval University in Quebec. And now Fermi was planning to leave in early 1939. Only [Edoardo] Amaldi would remain in Rome. 

In the early morning hours of November 10, 1938, Mrs. Fermi received a call informing her that Professor Fermi would receive a telephone call from Stockholm at 6:00 that evening. It was the Nobel Prize. The four years of patient research, the broken and unbroken tubes of beryllium powder and radon, the races down the hall of the physics building, the many tests, the paraffin blocks—all had finally culminated in the Nobel Prize. The Secretary of the Swedish Academy of Sciences read the citation over the phone. “To Professor Enrico Fermi of Rome for his identification of new radioactive elements, made in connection with his work of nuclear reactions affected by slow neutrons.” The Fermis immediately altered their plans to leave Italy sooner. Emilio Segrè recalls the incident.

Emilio Segrè: When he received the Nobel Prize, he decided to quit in December and he passed word to American friends that circumstances had changed, and that he would be receptive to an offer in America. Then he got the Nobel Prize, and he was notified confidentially that he was going to get the Nobel Prize. And so that when he knew this, he made his preparation and went to Sweden, and then from Sweden, went directly to Columbia [University].

Narrator: Fermi, his wife, two children, and a maid boarded a train on December 6, 1938, bound for Stockholm. He left his laboratory, his equipment, his colleagues. Enrico told Italian officials he was making a six-month visit to New York. Sixteen days later, on December 10, 1938, Enrico Fermi and American novelist Pearl Buck sat in center stage of the concert hall. They were presented their Nobel Prizes by King Gustaf V of Sweden. The Fermis left Southampton [United Kingdom] aboard the Italian liner Franconia on Christmas Eve, 1938. The crossing would take nine days. He would soon be free of Fascist interference to continue his work. It was mid-winter when they arrived in New York. Mrs. Fermi remembers.

Laura Fermi: We arrived the 2nd of January, 1939. It was our first cold winter—really cold winter. We lived on 116th Street on Riverside Drive and there is some kind of a funnel-like entrance to 116th from Riverside Drive. I remember my son who was crying on the street because of the wind and the cold.

Narrator: During the month that the Fermi family was en route to America, a flurry of excitement was gripping the scientific world. The strange unexplained disintegration substances that Fermi’s group had created in the laboratory in 1934 were byproducts of a new process called fission. Importance of this discovery was carried to America by the great Danish physicist, Niels Bohr. He arrived in New York on Sunday, January 16, 1939 at the West 57th Street Pier, aboard the Swedish liner Drottningholm. With him was the news that Otto Hahn and Fritz [Friedrich] Strassmann had discovered the fission of uranium at the Kaiser Wilhelm Institute of Berlin, and Lise Meitner had explained it. Mrs. Fermi remembers.

Laura Fermi: Perhaps more important, I remember when Bohr arrived just two weeks after we did. And we had been almost the Bohrs’ guests in Copenhagen when we went through to come to the United States. We went to meet him and from then on things started to happen. I remember he was always talking about war, the possibilities of war, and he was very pessimistic.

Narrator: Also on the dock in New York when the Drottningholm dropped anchor was a former student of Niels Bohr, John Wheeler.

John Wheeler: The day that I met Bohr was the beginning of work on fission. He soon had to go back to Denmark, but we had great discussions at that time—[Eugene] Wigner, Fermi, ‎[Leo] Szilard and other colleagues—about what would be the future of fission. I can remember Bohr saying that it would be impossible to think of making a weapon—that it would take the efforts of an entire country to do it. Little did he realize that it would be the efforts of three countries involved— England, Canada and the United States.

Narrator: The epidemic speed by which things happened was phenomenal. The world of physics was aflame with news of fission. Herb Anderson, then a graduate student at Columbia University, gives personal testimony to Bohr’s own excitement.

Herb Anderson: Fermi arrived and then Niels Bohr came with his great news about this new process called fission. When he came to the laboratory, he arrived in New York and he wanted to talk to Fermi right away. So he came immediately to Columbia, and looked for Fermi and did not find him, but he found me. I was sitting in the lab, and he was so full of his news that he began to explain to me about the fission.

Narrator: Within days of Bohr’s arrival, four American laboratories had experimentally confirmed the fission process. Mrs. Fermi recounts the activity.

Laura Fermi: Enrico explained it to me and shortly after that they stopped talking about it. I would say that they announced their thoughts at a meeting that must have taken place around January 30 or something like that—one week or two weeks after Bohr’s arrival. Then early spring, they had the secrecy. The letter that Einstein signed, he signed it in August, but I think they started thinking about it quite a bit before. They want twice to talk to Einstein.

Narrator: The neutrons which scientists were using to verify the fission process were old friends to Fermi. After all, he was the greatest living expert on neutrons. They answered many questions that had troubled him back in the physics building in Rome in 1934. Herb Anderson and Mrs. Fermi recall his motivation.

Anderson: Fermi, had had such a great reputation working with neutrons, and would naturally enter into this field as sort of a natural sequence of events. He would feel that it would be a dereliction not to go into it.

Laura Fermi: In a sense, Enrico picked the work up when he heard about the discovery of fission, because fission explained what he had done in Rome and what they had not understood was going on. It was all the same chain of things and going on in the same line.

Narrator: The first job: look for the hypothetical neutrons; define the heavy pulse of ionization from fission. This required an experiment. Although Fermi was a newly appointed Professor of Physics at Columbia University, he had no experimental apparatus. Herb Anderson remembers.

Anderson: I had constructed an ionization chamber and a linear amplifier—the popular sort of equipment for research in those days. Here was Enrico Fermi, famous nuclear physicist, just back from having won the Nobel Prize for his discoveries with slow neutrons, in a new country and a new university with no apparatus whatsoever. This was a sorry state for such a great man to be in, and so I said, “Look Professor Fermi. I have all this equipment and there are experiments that ought to be done to prove the existence of this fission process to demonstrate the energy release. Why do we not work together? I need a professor who will sponsor my thesis, and you don’t have all the equipment that I have.”

Narrator: The same research work was also being tackled by a second group at Columbia led by Canadian-born Walter Zinn and Hungarian Leó Szilard. The two groups published their results side by side in the Physical Review. The catalyst in this fever pitch activity was the knowledge that fission had been discovered in Hitler’s Germany, which had just gobbled up the rest of Czechoslovakia. It was an implied race to demonstrate a nuclear chain reaction.

On March 16, 1939, Dr. George Pegram, Chairman of the Physics Department at Columbia, wrote the Navy Department, “Professor Fermi is Professor of Physics at Columbia University and was awarded the Nobel Prize. There is no man more competent in this field of nuclear physics than Professor Fermi.”

Later, both Pegram and Fermi went to Washington to apprise the Navy Department of the dangers and prospects of atomic physics. Their evaluation of future results was filled with question marks and skepticism. General Leslie Groves, who later directed the Manhattan Project, remembers.

Leslie Groves: I think Pegram and Fermi came down to talk to the Navy Department about it, and when they were asked about what they thought of it—did they think it would succeed—Fermi said, “Well I do not know whether to work or not.” Well that is no way to get support from anybody that you want to get money from.

Narrator: It took the August 2, 1939 letter by Albert Einstein to President Roosevelt to convince the American government. A few weeks later, on September 1, 1939, Hitler invaded Poland. Much of the impetus for alerting the President came from foreign-born scientists, aliens who had first-hand experience with Fascist methods. Although an advisory committee on uranium was formed, the research moved no faster than its natural pace. Soon the first lattice structure of graphite and uranium was set up at Columbia. Fermi and Zinn’s groups were looking for a material to slow down the neutrons. The only material pure enough and somewhat available was graphite—good for making pencils, good for making art glass, good for oiling locks. The work on the exponential piles began with lattices of uranium and dirty, slippery carbon. Walter Zinn and Herb Anderson recall Fermi’s trait of pitching in no matter what the work.

Walter Zinn: The work was hot, dirty and heavy. Fortunately, Fermi was able to recruit a fraction of the Columbia football squad to assist in this effort, since in those days football players were expected to earn some of their support by doing useful work for the university. It was characteristic of Fermi that he participated in this work on an equal basis with the athletic brawn. I could not say the same is true for the rest of us.

Anderson: It didn’t make any difference whether it was mental work or physical work or just the worst kind of tedium. He always felt that he should do more than any other single person.

Narrator: Fermi always displayed unbounded energy and physical stamina. At the laboratory, he was the first to arrive, the last to leave. His basic philosophy was honesty comes before modesty. He was more prone to deeds than to talk. His most disarming trait: a lack of formality. Dr. Henry DeWolf Smyth, author of the Smyth Report, recalls an example.

Henry DeWolf Smyth: Professor Fermi was doing some work on our cyclotron at Princeton. The cyclotron there was down in a deep pit in the basement, not a particularly attractive place to work, but we didn’t worry much about that in those days. I went in one day to make sure that everything was all right. After all, Fermi was a guest; he was coming down from Columbia just for a few experiments. From where I came in, I could look down into this pit. What I saw was Professor Fermi and one graduate student moving a table under the direction of another graduate student, and I thought that was the kind of cooperation that was good.

Narrator: It was a characteristic Fermi exemplified throughout his life. Later in Chicago, George Weil crystalizes the trait perfectly.

George Weil: And I recall when representatives of DuPont [Company] came to visit Fermi. They looked in his office and he was not there. They looked in the laboratory and he was not there. They finally located him on the floor in a big lab coat with a great big shears cutting up some tin. It sort of shocked them that a Nobel Prize winner would not be sitting behind a plush desk directing things. But Fermi was not that kind of a person. He made the measurements. He dashed down the halls. We had a limited time in which to make the measurements. He did everything. And his facility in interpreting the measurements was just unique. Nobody had that facility.

Narrator: It was now December 6, 1941. To speed up the atomic research, Vannevar Bush, Director of the Office of Scientific Research and Development, reorganized the project. Arthur Holly Compton of the University of Chicago was put in charge of the uranium work. All effort became concentrated in Chicago. Groups from Princeton and Columbia transferred to Chicago, and a metallurgical laboratory was established. The next day: Pearl Harbor, and the lid of secrecy closed down on the project. Mrs. Fermi remembers.

Laura Fermi: They imposed secrecy on themselves and then I did not hear anything for years until the Smyth Report was ready. Then one day – we were still in Los Alamos so it must have been 1945 – Enrico came with a mimeographed copy of the Smyth Report and said, “Maybe you would be interested in reading this.” He did not volunteer any help so it was pretty hard going, but then I understood what had gone on—why the secrecy, the pile. We did not know anything about the pile.

Narrator: Ten years after the secrecy, Enrico Fermi himself dispelled some of the misconceptions about who imposed the secrecy.

Enrico Fermi: Secrets in science did not exist to any appreciable extent before the war. The military importance of science appears to have brought the necessity of at least some amount of secrecy. In this respect perhaps, many people believe that keeping secret results in the field of atomic fission that could lead to the development of the atomic bomb was imposed on the scientists by the military authorities. The truth is quite different, and the first agreements to keep certain results confidential were entered into freely among scientists in this country long before the government or the armed services manifested any interest in the matter.

Narrator: In the spring of 1942, Fermi moved to Chicago. The work on sub-critical size piles was continued. The objective: create a chain reaction at the earliest possible date. Fermi, Szilard and Wigner had already worked out the theory. These exponential piles required only about one-twentieth the materials of a chain reacting pile. Walter Zinn underscores their importance.

Zinn: By the way, this exponential experiment, which was a very powerful tool, was the invention of Fermi and was used in a wonderful manner by his very powerful analytical techniques.

Narrator: Many experiments and calculations were performed. There were thirty experimental sub-critical piles constructed and tested before the final pile was begun. Herb Anderson remembers.

Anderson: I think the interesting fact about it is that it was a major enterprise. It could be carried out very effectively by a small group of physicists alone without any engineers and without any design, without any formal planning of any sort other than what went on in our own heads. The design of this thing was made from day to day, and was adjusted according to the material that was coming in.

Narrator: Everybody from technicians to top administration gained immense confidence in Fermi’s ability and scientific judgment. Building and testing these exponential piles was almost second nature to Fermi. After all, he had been building piles since the first weeks in 1939. George Weil recalls a typical episode.

Weil: I recall one incident where one of our group was supposedly doing calculations. He broke his leg on a skiing trip, and so he was not able to do much work. Fermi gave him an assignment to calculate theoretically what was going on in these exponential piles, and he must have spent at least two or three weeks on this calculation. I was there one Saturday afternoon making measurements, and Fermi came in and he sat down. And he said, “Well, I think I will just check what so-and-so did.” In half an hour he had gone through the whole thing. Theoretical physics or mathematics, whatever you want to call it, was like a language to him. He could see the peaks and forget about the hills. He was a very intuitive man.

Narrator: Spring turned to summer. With each exponential pile, more data, more confidence. The scene under the west ends of Stagg Field was like a coal mine—men drilling graphite bricks, cutting them, carrying them, stacking them, others making measurements, others checking the critical size of the piles. The physicists worked twenty-four hours a day in two shifts. Walter Zinn recalls the routine.

Zinn: This was now the third year not only working full time. I mean working every moment that one could get on it to finally see the chain reaction, which we recognized. No question at all of supreme importance in both science and in the application of science.

Narrator: The full responsibility of the project was now under the newly formed Manhattan Engineer District. The methodical step-by-step approach to achieving a chain reaction was all Fermi’s idea. He was the guiding genius, the infallible oracle, completely self-confident, wholly without conceit. Herb Anderson and John Wheeler endorsed his methods.

Anderson: Even though it looked like an indirect method to make a slow chain reaction in order to get atomic bomb, he felt instinctively that we would learn so much about the principles, the basic scientific facts. That what we would learn would clear the way to what we were looking for in the end much more quickly than anybody else.

Wheeler: Of course, that was something that Fermi insisted on very strongly. That this reactor, and having the reactor succeed, was the first step before you could ever think of building a bomb. Although in practice, if you had had uranium-235, you could have put it together to make a bomb without building one of these piles. But Fermi insisted on this necessity of proving the principle and understanding it.

Anderson: So what Fermi was trying to do is to impress them on what a marvelous thing this was. And even though he had never tried it before, he prepared himself very carefully, and he had calculated what the reaction would be as he took each step.

Narrator: The original plan: build a final critical pile at the Argonne site, a new building far from the urban complex west of Chicago. It was scheduled to be finished by October 20. Labor strikes and construction difficulties delayed its completion. A decision had to be made. Some administrators wanted to wait—wait until Argonne was ready. Fermi himself was impatient. Herb Anderson explains.

Anderson: Fermi, who never liked the idea of all this formality anyway that went on. It would hold things up. He said, “Look, I can build the whole thing in the west end. It will take six weeks. Why don’t you let me do it?”

Argonne National Laboratory