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Peter Vandervoort’s Interview

Manhattan Project Locations:

Peter Vandervoort is an American astrophysicist and professor emeritus at the University of Chicago. In this interview, Vandervoort shares stories about the university’s role in the Manhattan Project. He describes in depth how different buildings on its campus were appropriated for the project. He later discusses his interactions with the university’s distinguished physics faculty members after the war, such as Nobel Prize winner Subrahmanyan Chandrasekhar, who was Vandervoort’s Ph.D. advisor in the 1950s. Vandervoort also talks about the university’s community outreach efforts through the years. He concludes the interview by discussing the contributions of women to physics.

Date of Interview:
November 17, 2016
Location of the Interview:


Cindy Kelly: Okay. I’m Cindy Kelly. It is November 17, 2016. I’m in Chicago, Illinois, and I’m with Peter Vandervoort. I would like first to ask Peter to say his name and spell it.

Peter Vandervoort:   I am Peter Oliver Vandervoort. Vandervoort has now been spelled in an Americanized way, V-a-n-d-e-r-v-o-o-r-t. 

Kelly: Great. Thank you. Before we get into your personal history, I’d like you to kind of give us a little tour, help us with identifying the people and activities associated with the various properties on campus that were associated with the Manhattan Project.

Vandervoort: The Quadrangle Club is the faculty club of the university. The dining room was a venue for almost daily luncheons for many years, attended by physicists and chemists. That was a very strong tradition. The club was used by other groups. In particular, there was a faculty group that met monthly during the academic year for dinner and for a research talk by one of its members. One of the interesting things: perhaps the first discussion that preceded the Metallurgical Lab occurred, as far as I can tell, in May of 1940 when Samuel Allison gave a talk to the club entitled “U-235 and All That.”

That was in that period between the discovery of nuclear fission and the imposition of censorship by the government on public discussions of nuclear research. There was this window of public discussion of nuclear fission, and its potential as an energy source and its potential as a weapon, that was probably fairly public for a year or two before the curtain of secrecy came down.

An interesting bit of history: Leo Szilard lived in the Quadrangle Club for a few years. It was a place where the veterans of the Manhattan Project, the participants of the Manhattan Project, met regularly for lunch. Presumably, their discussions were not sensitive from a point of view of the Met Lab, but they became a community around the lunch tables.

I was a student in the university from 1951 to 1960, and in my time, Eckhart Hall was the home of the Departments of Physics and Mathematics. It was built around 1930, which was essentially the second building boom on the campus of the university after its foundation. It’s interesting in the history of the Met Lab, because it was appropriated for use as the administrative building of the Met Lab.

I mentioned in connection with the Quadrangle Club that we had a faculty group that met for dinner and talks, lectures, but when I looked up the records of that club, I discovered that I had a typescript of the membership of the club. Office addresses were typed in, but then a number had been corrected by hand. For example, Sam Allison had moved from Ryerson, another physics building, to Eckhart at one point. The mathematicians had been moved out of Eckhart Hall and were now located in other offices on the campus. Suddenly, the use of Eckhart changed very abruptly with the beginning of the Met Lab. Eckhart was the administrative building for the Metallurgical Lab.

There is a rather iconic photograph of participants in the Manhattan Project that was taken on the front steps of Eckhart Hall, I believe around 1946. In any case, at the end of the Second World War, and that photograph contains a number of the participants in [Enrico] Fermi’s experiment to bring the Chicago Pile-1 to criticality. But there were other members of the Manhattan Project that were in that photograph, who had not been present at the first chain reaction, but who were very much involved with the development of reactor physics.

Sam Allison was a member of the Physics Department from the 1930s until his death in the early 1960s. When he came to Chicago, he was an X-ray physicist. He collaborated with Arthur Compton on a book on X-ray physics, but in the late ‘30s his interest began to shift to nuclear physics. I’m proud to have been a student of Sam Allison in one of his classes. He was on my dissertation committee, and it was just a privilege to be at an institution where one can know such extraordinary people.

Leo Szilard was a very remarkable physicist, but I would say a contrarian. He was not particularly gifted in hands-on experimental work, but he was very imaginative and indeed, he foresaw, in a sense, the discovery of nuclear fission. Before the discovery, or the observation of fission, he imagined the construction of a nuclear reactor. Therefore, at the time of the Metallurgical Lab, he already had patents on the process.

He was very much a character. Later in his career, he became interested in biophysics. He wrote some rather charming science fiction, and was very much a member of the university. He was very much an advocate for the control of nuclear processes. In particular, I think he was one of the leaders in the discussion as to whether or not the atomic bomb should be used during the Second World War. I think that he was one of the intellectual leaders of the group that favored careful control and very restrained use of nuclear energy on this campus.

A number of buildings on the campus were put under security. There were guards. There was very limited access. In particular, the two physics buildings, Eckhart, that we’ve already discussed, and Ryerson, the other physics building, were appropriated. Eckhart for administration, Ryerson for physics, and then the two chemistry buildings, Kent and then Jones, were also appropriated for chemistry. Those buildings were under guard. A colleague of mine was here as an undergraduate in 1943/’44, and he does recall that those buildings were secured.

Kelly: Were these armed guards?

Vandervoort: That I don’t know, but my guess is that they could well have been. They might very well have been U.S. Army military police. After all, Leslie Groves, General Groves, was head of the Manhattan Project and so in a sense, it was a program of the United States Army.

Kelly: You keep talking about the Metallurgical Laboratory. Can you tell us a little more when it got started, who headed it?

Vandervoort: The university’s contribution to the Manhattan Project was organized under the so-called Metallurgical Laboratory. The name was chosen to obscure the fact that it was the venue for nuclear research leading to various applications of nuclear fission. It was referred to by the community as the “Met Lab” quite often. In connection with these discussions, when we say the Met Lab we do mean the Metallurgical Lab and we do mean the contribution of the University of Chicago to the Manhattan Project.

Arthur Holly Compton, who was a very distinguished member of the Physics Department, a Nobel Laureate in X-ray physics, important discoveries that advanced the development of quantum theory. He was at one point head of the Physics Department and then dean. I’m not sure if his deanship was restricted to the physical sciences or it covered the biological sciences as well. There was a reorganization of the university under Robert Maynard Hutchins. At any rate from our point of view, Arthur Compton was perhaps the leading member of the physics community on the campus at that time. He was the scientific leader of the university’s involvement in the Manhattan Project.

Early in the project, they were setting up laboratories at Columbia University. Fermi and Szilard did early work at Columbia University and then were moved to Chicago. The Met Lab was established, and the Met Lab was a cover. That is to say it would not have done to have called it the “nuclear research lab,” or anything of that sort. It would have been a giveaway. So, the Metallurgical Lab is notorious on campus as having been the scientific venue for our research in the Manhattan Project, but the name was chosen for the sake of security.

Interestingly, there was a potential security breach through the student newspaper, and I believe it was in connection with their report on Compton’s departure to become President of Washington University. The article, as I recall, said something to the effect that Compton’s research was involved in breaking up atoms. The university, or the Manhattan Project security on campus, promptly came in and reprimanded the editor of the student newspaper, the Chicago Maroon. Not only that, they went around campus and appropriated all of the copies of the Maroon that they could lay their hands on. So there was a certain sensitivity to the security issues.

The Council Tree is really connected with the challenge to the scientific participants in the Manhattan Project. Scientists live in a world where by and large you discuss everything, and you make sure everybody hears the same words. That’s just a culture that does not accommodate to the requirements of security. They did learn and they did understand that it was important to have sensitive discussions under circumstances in which they would not be overheard.

The practice developed of going outside Eckhart Hall. In front of Eckhart Hall there was a tree that came to be known as the Council Tree. Very often when participants in the Met Lab had some sensitive material to discuss, they would go out and stand by that tree with some confidence that they could have a discussion on very sensitive issues with very little chance of being overheard by the wrong people.

That tree continued to exist until the administration of Edward Levi as president, so we must be talking about the late 1960s or early 1970s, when the tree died. It was a bit of a shock to people and there was a little bit of mourning over the loss of the tree. The tree was very carefully removed and enough lumber was preserved to construct a bench, which has now been in various locations on campus and is known as the Council Bench. 

The bench that was constructed from the lumber of the Council Tree is at this time located in the lobby of the Jones Chemistry Laboratory.

I mentioned earlier that Eckhart Hall was constructed around 1930 as part of the second building boom on the campus of the university. Ryerson, an older building located just to the west of Eckhart, was the first physics building on campus of the university, built around 1894. It was the scientific home of a very distinguished group of scientists. Albert Michelson worked there; [Robert A.] Millikan worked there; Compton worked there. Robert Mulliken, a faculty member in my time as a student, was there. It was the physics building at the beginning of the university.

Eckhart and Ryerson are now used mainly for the Departments of Mathematics, Statistics and Computer Science. The physical sciences have moved to more modern facilities elsewhere on campus.

In my time, there were two very distinguished members of the Physics Department, William Zachariasen and Robert Mulliken, who were located in that building. I had connections with both of them.

Zachariasen was a physicist from Norway. He was a very distinguished X-ray crystallographer and as part of the Manhattan Project, he was responsible for the exploration of the chemical and metallurgical structure of the transuranic elements that were produced as a result of the Manhattan Project. He played an extremely important role in establishing the basic science underlying the chemical and physical behavior of the transuranic elements discovered or created in the process of the Manhattan Project. I had a course in mathematics from Zachariasen. He gave the entire series of lectures without a note. He made one mistake on the blackboard, muttered, “Damn,” corrected it and completed the lecture and completed the course.

Now, another member of the Manhattan Project, who actually was a very young member – he completed his Ph.D. after the Second World War – was Mark Inghram. When I read Mark Inghram’s essay in the biographical memoirs of the National Academy of Sciences, he described taking a course from Zachariasen in mechanics. Zachariasen would come into the room with a notebook that he would put on the table, but rarely opened it. In Inghram’s recollection, Zachariasen opened the notebook once. He was disturbed about a formula that he had written on the blackboard and he opened the notebook to check what his notes said, and he realized that what he had on the blackboard was correct, but it was in a form different from what he had in his notebook. I was very gratified by the parallel of Mark Inghram’s story and my story, because Mark Inghram was the chairman of the candidacy examination committee with which I became a candidate for the Ph.D.

Just a comment: many veterans of the Manhattan Project were my mentors and teachers. So, I know more about the veterans than I do about the project. I mentioned Robert Mulliken; he was a very distinguished expert in atomic and molecular physics. He was a Nobel Laureate. He was a member of the examination committee in which I got admitted to the Ph.D. candidacy. He was the thesis advisor of Leona Marshall Libby. These connections just accumulate.

Well, Ryerson is now given over mainly to computer science and statistics.

The next building is the Kent Chemical Laboratory. Kent was the first chemistry building built on the campus of the university. It dates from the 1890s. It is a contemporary of Ryerson. As I mentioned, Kent and Ryerson were part of the first building boom on the campus. Eckhart and the Jones Chemical Laboratory were part of the second building boom. The first building boom was the 1890s; the second one was 1930, plus or minus a couple of years. Kent was the principal chemistry building for many years. It now serves mainly as a venue for instruction. The instruction laboratories and most of the lecture and seminar rooms are there.

Kelly: Was it used in the Manhattan Project?

Vandervoort: Kent and the second chemistry building, Jones, were both appropriated for chemistry during the Manhattan Project. That line of buildings ranging from Eckhart at the east end of the block to Jones at the west end of the block—Eckhart, Ryerson, Kent, Jones—were all secured for the purposes of the Manhattan Project.

The George Herbert Jones Chemical Laboratory was completed around 1928. It was the more modern chemistry building during my time as a student. Perhaps from the point of view of the history of the Manhattan Project, the most important or significant fact about the Jones Laboratory is that it was on the 4th floor of Jones that a team led by Glenn Seaborg first weighed the very tiny sample of plutonium that had been produced elsewhere. It’s a kind of benchmark in the chronology of the Manhattan Project and the Metallurgical Lab.

There is now a display connected with the weighing of plutonium in the lobby of the Jones Laboratory, and most of that display concentrates on the weighing of plutonium. However, there are two other objects of some interest. One is a model of Chicago Pile-1 constructed from Lego, and as far as I can tell, it is a pretty good representation of the shape of the pile.

The other artifact in the lobby of Jones is the Council Bench itself, which was constructed from the tree at which scientific participants in the Met Lab had sensitive discussions for security reasons. So that lumber undoubtedly heard many very significant sequences coming from the Metallurgical Laboratory.

The physics and chemistry buildings, Eckhart, Ryerson, Jones and Kent, are for all practical purposes located on 58th Street, although they are set back from the street because of the geography of the campus. The West Stands was located along Ellis Avenue between 57th and 56th Streets. It was the part of Stagg Field, which was the original athletic field on the campus of the university. When I was a student, the West Stands loomed over Ellis Avenue. It was used by the James Franck Institute for the temperature physics. In fact, it was the venue for the Franck Institute until a proper building was constructed for that institute.

When I say the James Franck Institute, I should say it was the institute created as the institute for study of metals at the end of the Second World War. Then the laboratories for the liberal arts courses in the natural sciences were located on the second floor of the West Stands during the 1950s. I guess I’m one of the last people to be able to claim to have worked in the West Stands before it was demolished.

It was a secure site in the same sense that the chemistry and physics buildings were secured. The Chicago Pile-1 was constructed on the main floor of the West Stands. The building was eventually taken down. It has been replaced by a number of other structures, and in particular, it is the site of the sculpture “Nuclear Energy” by Henry Moore.

The West Stands was part of the seating for the University of Chicago’s athletic field, Stagg Field. Stagg Field plus a gymnasium and the North Stands occupied a city block. By the time of the Second World War – by the time of the Manhattan Project – the university had left the Western Conference, or was leaving the Western Conference, and there was a substantial de-emphasis of intercollegiate athletics. So the stands were available for other purposes. Football had been abandoned at the University of Chicago and so there were very few events that required massive seating.

I guess the point was that the West Stands was an industrial quality structure suitable for scientific research of the kind that was required for the construction of CP-1. In any case, it was appropriated and secured as part of the Metallurgical Lab, and was the venue for the first controlled nuclear chain reaction in December of 1942.

Kelly: Do you remember, were the squash courts still there when you were a student?

Vandervoort: I do not remember squash courts in the West Stands. My suspicion is that they had disappeared. The West Stands was certainly not used as part of the athletic program at the university when I was a student. There were still tennis courts, clay courts, under the North Stands, but I think the West Stands never returned to use by the athletic Department.

Kelly: Was there research conducted?

Vandervoort: I was a laboratory teaching assistant in the West Stands in 1953 to probably late ’54, or early ’55. There was a low-temperature facility on the ground floor, which housed a hydrogen liquefying facility. Then the undergraduate laboratories for liberal arts courses and the natural sciences were located on the second floor. During my time there, a hydrogen liquefier similar to the one that we had in the West Stands blew up in the Kamerlingh Onnes Laboratory at Leiden University. When the Legal Department realized that we had a similar hydrogen liquefier in the West Stands, the college instruction laboratories were very quickly removed.

Vandervoort: [Subrahmanyan] Chandrasekhar was my mentor. He was another of the Nobel Laureates whom I collected around the university. Chandrasekhar was probably the most distinguished theoretical astrophysicist in the middle of the 20th century, worldwide. Interestingly, I became his student by accident.

Subrahmanyan Chandrasekhar was my Ph.D. thesis supervisor. I was a graduate student research assistant at Los Alamos in the summer of 1956, working in the emulsion laboratory of Louis Rosen at Los Alamos. “Chandra” is our nickname for Professor Chandrasekhar. Chandra was at Los Alamos consulting on the fusion program that was going on at Los Alamos in the 1950s.

I was dithering. I did not know whether I wanted to do astrophysics or particle physics, and a classmate said, “Well, tell me what you want to do.”

After a moment, I said, “Astrophysics.”

He said, “Fine. Chandra is probably the only astrophysicist within several hundred miles. Why don’t you go talk to him?” My classmate and I had been students in Chandra’s class in quantum theory the previous academic year.

I had done reasonably well in the course, but my reaction was, “Oh, Chandra doesn’t want to talk with me.”

My classmate said, “Well, you have nothing to lose. Worst case scenario, he asks you to leave. You are no worse off than you would be if you didn’t see him.”

I went to see Chandra and he remembered me from the course. He asked me what the purpose of my appointment was. I said that I had decided that I wanted to continue in astrophysics. He said, “Well, I have two pieces of advice to offer. The first is take your Ph.D. in physics. A knowledge of physics will be very important in future discoveries in astronomy. The second is why don’t you work with me? I can offer you an assistantship.”

I’ve always wondered if I was so inarticulate that I didn’t make it clear that I was coming for advice and didn’t expect anything more. But, again, it’s a small world and Los Alamos figures very prominently in my own experience and history.

Well, Professor Chandrasekhar knew Henry Moore, who did the “Nuclear Energy” sculpture, essentially on the site, at least approximately, of Chicago Pile-1. Chandra once commented that he had been discussing the interpretation of the sculpture with Henry Moore, and Chandra pointed out that many people saw the sculpture as a representation of a mushroom cloud or a skull. Henry Moore’s observation was that that interpretation was rather banal—but interesting connections. I recall that my wife and I saw a model of the sculpture in the Netherlands when we were there for a sabbatical year, and so we knew what we should be looking forward to when we returned to Chicago. Again, an opportunity for contact with extraordinary people.

The sculpture, “Nuclear Energy,” is pretty much on the site of CP-1, and it is a tourist attraction. It’s not uncommon to see buses pause there and visitors out taking pictures of the sculpture. And taking pictures also of the plaques in front of the sculpture that commemorate the first nuclear chain reaction, and I think mark the site as a National Historical Site. 

Kelly: We even saw a visitor crawling inside the sculpture.

Vandervoort: You occasionally see young people taking naps there. [Laughter]

We are now on Woodlawn Avenue at a location a block or two from the main campus of the university, in front of what was the home of Professor Arthur Holly Compton. Professor Compton was the Dean of the Division of the Physical Sciences and previous to that Head of the Department of Physics. He was the leading physicist on the campus at that time.

He was a specialist in X-ray physics, in which he did work for which he received the Nobel Prize. But, at the time of the beginning of the Second World War, his interests had switched to cosmic ray physics. He was a leading figure in bringing the university into the Manhattan Project, and attracting distinguished scientists to the program. He continued his leadership through the Second World War and eventually accepted the presidency of Washington University in St. Louis.

Like many members of the faculty, he had a home in the neighborhood of the university. The university was very proud to be able to say the large fraction of the faculty lived within walking distance of the campus, which meant that the members of the faculty, and in particular the veterans of the Manhattan Project were also neighbors, who shared social and cultural interests in addition to their scientific connections.

I don’t really know the extent of the communication between Compton and Hutchins. Hutchins was, of course, chancellor of the university at the time, and I don’t know the extent of the communication between Compton and Hutchins regarding the plans to do the criticality experiments with CP-1. Hutchins must have then known that the reactor was being constructed in the West Stands. I cannot imagine that he would not have understood that some serious experiments were contemplated. I could imagine that Hutchins might have preferred not to know too many of the details.

The university benefited at that time from having a leader who was on very good terms with members of the scientific community. My guess is that Hutchins had a great deal of trust in Compton. I know of other connections in which relations between faculty and Chancellor Hutchins were of the highest quality. Hutchins was very much involved with what was going on.

I’m going to digress. Hutchins took a very friendly view to the development of the physical sciences at the University of Chicago following the Second World War. He led in the creation of two research institutes, the Institute for Nuclear Studies, which is now the Enrico Fermi Institute, and the Institute for the Study of Metals, which is now the James Franck Institute. We tend to name things after our Nobel Laureates. The institutes were created, at the end of the Second World War, and they were intended to bring together chemists, physicists, geophysicists, biophysicists in a very interdisciplinary setting. Hutchins’s leadership in continuing the quality of the science done on the campus of the university following the Metallurgical Laboratory and the Manhattan Project was very important.

Willie Zachariasen became Chairman of the Department of Physics around 1945. It was right at the end of the Second World War. Prior to Zachariasen’s administration, the administration of the Physics Department had been a rather autocratic operation. The head of the department was the boss and was not really expected to consult with others before making important judgments and decisions.

Zachariasen turned the Physics Department into a highly democratic community. Early on he convened the faculty to discuss new academic appointments in physics. At the end of the meeting, the faculty had agreed to recommend to the university the appointment of Enrico Fermi, Edward Teller, Walter Zinn, Robert Christy, and John Simpson, all veterans of the Manhattan Project to the faculty of the Department of Physics. Zachariasen took the recommendation to Robert Hutchins that afternoon, and by the end of the day Hutchins had approved all five appointments. 

One other example. Otto Struve was for many years the Chairman of the Department of Astronomy and Astrophysics and Director of the Yerkes Observatory. I’m told that someone once asked Struve, “How does it happen that the Department of Astronomy was so well-treated during the 1930s when the Depression imposed serious constraints on the university’s budget?”

Struve is said to have replied, “You must understand, astronomy was the only science that Mr. Hutchins understood.” Now, I always thought that was a nice fairy tale, but then I came across a published paper by Struve, in which he was very generous in his praise of Hutchins for the support that Hutchins had given to the Department of Astronomy and Astrophysics when we joined with the University of Texas for the creation of the McDonald Observatory, which for a number of years was the second largest reflecting telescope in the country.

Hutchins was a very important player and leader in the pursuit and improvement of science on the campus of the university. He has to be listed as one of the important veterans of the Manhattan Project.

I have to confess I’m a fan of Robert Maynard Hutchins, because I benefited from the college curriculum that he and Mortimer Adler created.

Kelly: What was that?

Vandervoort: It was designed to accept students after two years of high school, and it was a program of about three and a half years solely of the liberal arts. Interestingly, I learned yesterday at a meeting of the Board of the Adler Planetarium that we had sent one of the artifacts from our collection of historical astronomical instruments to the University of Louvain in Belgium for an exhibit commemorating the 500th anniversary of the publication of Thomas Moore’s Utopia. My reaction is, “I read Utopia in the Hutchins College!”

Kelly: At the end of those three and a half years, you get a—

Vandervoort: I had the ideal history. I entered the college at the age of 16 after three years of high school. I graduated at the end of my third year, so I was 19, and I had already done my freshman physics. After another year of study, I received a Bachelor of Science degree at the age of 20, and a master’s degree at the age of 21. So I was 21 years old, having gotten the liberal arts degree and then a Bachelor of Science degree in physics, and then a Master of Science in physics when I had the summer assistantship at Los Alamos.

There’s another good thing. When I was courting Frances, my wife, we had terrible arguments about the philosophy of education. Fran, who was going off to the University of Michigan – she had just graduated from high school – was very critical of what I was arguing. But I had the advantage. I had Robert Maynard Hutchins on my side. When she started reading his books, she said, “Hey, that’s pretty good.” So she transferred to the University of Chicago after two years at Michigan. She had the best of both worlds, as it turned out.

Elsewhere on Woodlawn Avenue was the home of Enrico and Laura Fermi and their family after the Second World War. It is one of the grand houses in Hyde Park, again, within a short distance of the university. 

I did not have the privilege of knowing Enrico Fermi. To the best of my recollection, I attended one physics colloquium by Fermi. I had a peripheral interest, because Fermi and my teacher, Subrahmanyan Chandrasekhar, collaborated on some astrophysics papers in which I took an interest as a graduate student. Chandra had a fair number of Fermi stories to tell. But I completed freshman physics in 1954. I should say that John Marshall, another participant in the Met Lab, was my teacher for three quarters of freshman physics. I had completed freshman physics in ’54 and was starting the intermediate level physics courses with Zachariasen and Allison. Fermi died in ’55 [misspoke: 1954].

A friend told me, and this must’ve been late in ’55, that there was a position available in what had been Fermi’s laboratory for an undergraduate to scan nuclear emulsions. I went to apply for that position. I was hired by Horace Taft, the son of Senator Robert Taft and the grandson of President William Taft. The leader in that department for practical purposes was Arthur Rosenfeld, who for many years was on the physical faculty at Berkeley, and eventually involved in significant environmental matters.

There was a wonderful group of younger students who were the last generation of Fermi’s students, who were completing their Ph.D. work under the supervision of other members of the faculty. I worked initially for Jerome Friedman, who became a distinguished professor at MIT and received the Nobel Prize in Physics for his work on the discovery of the character of the structure of fundamental particles.

It was a very significant research group. I fondly imagine that the spirit of Enrico Fermi still permeated that laboratory. Certainly, the former students of Fermi adored him. One hears wonderful anecdotes by people who were associated with him. But I was just a little bit too young and too early in my career to have any real benefit from the connection.

John Simpson was one of the five appointees that Willie Zachariasen took to Chancellor Hutchins in 1945. He was one of the younger participants in the Manhattan Project. He was a very junior faculty member when he joined the university faculty just after the Second World War.

John was a very remarkable man. He got interested in neutron physics, which of course, was the fashionable thing at the end of the Met Lab, but his interest shifted to cosmic ray physics. He became one of the leading figures in space science. Really beginning in the 1950s, he had a major program to monitor the incidents of cosmic rays on the earth at various places, locations on the earth. He had a monitor in the Andes. I’m not sure of the total list of sites for his experiments. He was doing ground-based cosmic ray physics in the ’50s, but when the opportunity came to go into space, he was one of the leaders. He had experiments on a very large number of missions put together by NASA.

There was a breadth there that was very interesting. I talked with him for the first time when I was going through a reception line after the wedding of a classmate. When I introduced myself to him, he immediately indicated that he knew the subject of my thesis project, although I had never had anything to do with him. Quite clearly, Chandra had told him something about what I was doing.

He was very good in his own way with undergraduates. He did not have a very good reputation as a lecturer, but he always had undergraduates working in the laboratory. When an experiment was finished and it was time to write the paper, it had been a team collaboration and the collaboration met. The graduate students, or the undergraduate students, who had participated in the experiment were at the table along with the post-docs and the research associates and the other colleagues. He was also very thoughtful in dealing with undergraduates who were about to graduate and leave. He would tell the young person, “I’m going to have to replace you. I want you to find for me a candidate and write a letter of recommendation.”

He spent a fair bit of time immediately after the war going to Washington to advise and advocate for civilian control of nuclear energy. In that effort, he became a colleague of Edward Levi, who was later president of the university and attorney general under Gerald Ford. Edward Levi and John Simpson became allies in the advocacy of civilian control of nuclear energy. Levi was acting as a legal consultant to one of the congressional committees, as I recall. It was clear that there was a very collegial relationship between Levi and Simpson, that I had a privilege of witnessing very briefly in a receiving line when I followed John Simpson in greeting Edward Levi. 

John really created space science at the university, and he created it in a way that connected it with the established Department of Astronomy and Astrophysics. There’s a legacy there that we all benefit from.

Mr. Levi was president of the university at a very difficult time in the history of the country. The 1968 concern over the Vietnam War, the disruptions of the Democratic National Convention, etc. There was an interesting development.

Around 1968, a basketball coach, Larry Hawkins, in the Chicago public schools, went to President Levi of the university and he essentially said, “If there is a message that you want to get to young people on the South Side of Chicago, have the basketball coach deliver that message. He may be the only adult that young people on the South Side of Chicago will listen to.”

The result was the creation of the Office of Special Programs, which Larry Hawkins came to direct. It was a program that became a model for outreach programs in the United States. The organizing principle was to get high school students on the South Side of Chicago to come to the campus and have reason to feel at home. The trick was we have athletic facilities. We’re going to let you use these facilities, but the quid pro quo is we also have classrooms, and we’re going to make you sit there for enrichment as well. There was this program of educational outreach and athletic activities, the carrot and a stick of a wonderful kind that has produced a wonderful generation of young African-American alumni from the South Side of Chicago.

The faculty became very much involved. One of the leaders was a mathematics professor, Paul Sally, who was really the most charismatic of people for this kind of a role. When I became aware of the program, Roger Hildebrand was the Chair of the Faculty Advisory Committee for the Office of Special Programs. Some years later, I became the chair of the outreach program. That outreach program was later embedded in in CARA, the Consortium for Astrophysical Research in Antarctica, and we continue in astronomy and astrophysics to have an outreach program, which looks after students, high school students during the academic year. Then we have special programs at the Yerkes Observatory in the summer.

This kind of outreach effort has been replicated elsewhere. One one of our tours of the campus we encountered Professor [Yau] Wah, who was looking after students from the Englewood neighborhood who were in a summer program of outreach. Looked after essentially by the Physics Department and the Enrico Fermi Institute. We have had other similar outreach programs through other departments as well. We try to be good neighbors to the community. There was an occasion when Larry Hawkins, the leader of that program, who created the program in 1968, received an award from the Hyde Park Historical Society. In attendance were now a number of alumni of that program, who are now at the level of middle management in various companies around the city.

It was a principle, have the basketball coach deliver the message and they’ll listen. Even now, we are helping students accommodate, and I think the most important aspect of this program is a young person can walk from a classroom, say Cobb Hall to the Ratner Athletic Facility with a sense, “I have something to do here and I belong here for that purpose.”

Well, in fact, we have an education and outreach officer in the Department of Astronomy and Astrophysics. We participate in a variety of programs. We also have connections with the Adler Planetarium that are quite strong. But, that’s a digression from—

Kelly: Maybe you can tie these two together, if it makes sense. After the war, the Manhattan Project leaders and how—what directions they took within the university.

Vandervoort: Well, the faculty, particularly in physics and chemistry when I was a student, was a community very much dominated, I would say, by participants in the Manhattan Project. Five members of the faculty taught seven of the physics courses that I took: Samuel Allison; Willie Zachariasen; John Marshall; “Murph” [Marvin] Goldberger; Darragh Nagle. They were obviously a community.

Maria [Goeppert] Mayer was on my dissertation committee. I had the privilege of being best man when Maria Mayer’s daughter married my best friend in the Physics Department. It was a bit of a family as well. It was a very striking experience to be in the presence. You’ve been invited to Mount Olympus. What can I say?

It was a very distinctive faculty, but it was a faculty that clearly was past the Manhattan Project, and the different individuals were going in their respective ways. The emphasis on low-energy nuclear physics, reactor physics, neutron physics, has passed largely to the national laboratories, where these subjects continued to be of interest in connection with weapons research. In particular, also with research on the possibilities for nuclear fusion as an energy source. 

The accelerator building, when it was completed, housed two of the high-energy accelerators in the world. The major one was a 250-million electron volt synchrocyclotron, at that time one of the largest accelerators in the world. There was a 100-million electron volt betatron. If you wanted protons, you went to the cyclotron; if you wanted electrons, you went to the betatron. These machines were the natural homes for research on accelerator physics, research on elementary particle physics and they were stepping stones to research on high-energy physics.

There was a natural drift of people. Fermi, for example, was very much a leader in that direction. The theorists wanted very much to go in that direction, because it was becoming clear that fundamental discoveries in physics were going to depend on the experimental use of high-energy accelerators. The attractive physics was in a direction other than the more practical concerns of the Met Lab and the Manhattan Project. John Simpson drifted into cosmic ray physics. Fermi was a leader in elementary particle physics. John Marshall and Darragh Nagle were leaders in accelerator physics, in elementary particle physics.

When Roger Hildebrand joined the Physics Department, he and Darragh Nagle developed the first hydrogen bubble chamber. Their bubble chamber was a little thing you could hold in your hand, about the size of a shot glass. That was the ancestor of these huge bubble chambers that have been associated at a certain history in elementary particle physics with the very large machines. This is an example of people being attracted to work addressing the most fundamental problems in science.

Cosmic ray physics: John Simpson, [inaudible]. John Simpson brought Peter Meyer into the Department. They became experimental physicists. They attracted theorists like Eugene Parker, but that was the particle physics, astrophysics connection. Cosmic rays are a part of astronomy, contrary to the prejudices of certain physicists. Cosmic ray, particle astronomy is still an important part of what we do in the department.

There were other people such as Robert Mulliken, who essentially had always done atomic and molecular physics, and essentially went back to atomic and molecular physics. Zachariasen continued to be an active X-ray crystallographer. He was a neighbor when our department was located in Ryerson. Mark Inghram was doing related experiments. Whom else should I be talking about? Of course, Mrs. Mayer continued as a member of the department, Maria Goeppert-Mayer, best known for her contributions to the nuclear shell model.

Chemists were involved: Harold Urey; Nathan Sugarman. I put Norman Nachtrieb in that group. I’m not sure what he did during the Second World War. It’s important to realize that the Manhattan Project was not the only big project during the Second World War. A member of my own Department, Gerard Kuiper, a very famous astronomer, was part of the Alsos Mission. Which was a mission headed by Sam Goudsmit, which was involved largely in collecting information about war research, and in particular, nuclear research in Germany during the Second World War.

Connections are very interesting. In May of 1945, the American Army had reached the Elbe River from the west, and they stopped at the Elbe River, because the agreement among the Allies was that the Soviets were to be in charge of the territory east of the Elbe River. Goudsmit and Kuiper were at a location on the Elbe River, when Kuiper learned that Max Planck, the discoverer of the Planck constant. Fair to say that Max Planck wrote the first paper in quantum theory right around the end of the 19th, beginning of the 20th century. He was by this time a very elderly senior citizen in the physics community in Germany.

Planck had taken refuge in a farmhouse on the east side of the Elbe River. At that point, this would have been May 16, approximately, of 1945. There was a no-man’s land between the Elbe River and the advancing Soviet Army. Max Planck and his wife were in the path of the advancing Soviet Army.

Gerard Kuiper got permission from Goudsmit to mount a rescue operation. He grabbed two enlisted men and commandeered a jeep. They crossed the Elbe River and they moved into no-man’s land, which was probably a very risky trip. They found Professor and Mrs. Planck. They offered to take them to Gӧttingen and safety in the American zone, and the Plancks were saved. It’s a story that I had never encountered until just recently, but it’s well documented in a number of places. I knew Kuiper when I was a student and I would not have put him in a Clint Eastwood role, except that, as I reflect on it, he had a Dutch pragmatism. “Here is a problem. This must be the solution. Okay. Let’s do it.”

The irony is that Goudsmit’s parents were lost in one of the Nazi concentration camps during the war. But, that’s another aspect of the Manhattan Project. I guess it’s part of the University of Chicago story that Kuiper was connected with at least one rather brave exploit. This, by the way, is recorded in the biographical memoirs of the National Academy of Sciences in a very fine essay, so it’s apparently a well-documented event. I’ve read about it in other sources as well, although Kuiper never said a word.

But one of the things that strikes me in this whole story—I was not involved in the Manhattan Project—but many of the participants in the Manhattan Project were among my teachers. I think I was exposed to a culture that was very much a legacy of the Met Lab and the Manhattan Project. I have a sense that there was very little discussion, public discussion, of the Manhattan Project. We were not being exposed to a message, well, you are benefiting from the legacy of the Manhattan Project.

We knew about the Manhattan Project. We lived in the shadow of the West Stands and we saw the plaque commemorating the December 2, 1942 events. But it was somewhat rare that we knew about those connections. We did know that a number of members of the Physics and Chemistry Departments would travel to Los Alamos, particularly during the summer, to consult on various programs there. As I mentioned, my mentor, Chandrasekhar, was there when I was working in Louis Rosen’s lab. Fermi went with some regularity. Richard Garwin went. We were aware that Los Alamos was in the itinerary of our teachers.

For me, the most striking exposure came in physics colloquia. There was an endowed fund created to support what were called the Louis Slotin Lectures. Louis Slotin had joined the physics Department as a research associate in the late 1930s, and was clearly a gifted young physicist, highly regarded, had a variety of collaborations across the campus. He was involved, in particular, in the construction and operation of the cyclotron that was constructed on campus just prior to the Second World War. He was recruited into the Manhattan Project and he died, tragically, in an experiment intended to measure the critical masses of elements like uranium and plutonium, critical masses for self-sustained chain reactions. 

An experiment that he was doing, known as “tickling the dragon’s tail,” involved bringing two subcritical masses of a reactive element together and monitoring the radiation emitted, and from the measurements trying to deduce what the critical mass of that particular element would be for a self-sustaining reaction. It was a very crude experimental technique. Essentially, he was pushing one of the subcritical masses with a screwdriver. The screwdriver slipped, the two masses came together. There was a massive emission of neutrons. He was exposed and he died tragically within a few days.

He was fondly remembered in the Physics Department. Sam Allison would make the introductions, and he really cared, and you just knew it was a tragedy. His recollections were very affectionate, and it was one of the rare occasions where there was a very explicit reference to the Manhattan Project, to the Met Lab and the Manhattan Project.

We knew that participants of the Manhattan Project were involved in the Bulletin of the Atomic Scientists, for example. This was a hotbed of activism in connection with the proper control of nuclear energy. But with this rare exception – I remember the lecture, or the introductions to these colloquia that Sam gave. I guess it was particularly touching, because Sam Allison was always a good source of a joke. He always had a quip of one kind or another.

Kelly: I think it tells a lot about how you felt about this tragedy and also about Sam Allison. It talks a lot about the fraternity of the physicists. You never met Louis Slotin, is that right?

Vandervoort: I never met Louis Slotin, very different generation. Of course, I have very fond recollections of Sam Allison.

For the last two years of my graduate work, I was resident at the Yerkes Observatory – that’s where Chandra was located – except for traveling to the campus once a week. We had two examinations for the Ph.D. There was a general examination which really sort of covered your course work and your background knowledge. Then there was the defense of the dissertation.

I would frequently ride to campus on Thursday with Chandra when he would drive in to the campus. So, the evening before my first examination was to be held, Chandra came to my office at the Yerkes Observatory to just discuss the plans to leave Williams Bay, Wisconsin, to come down to the campus. The rule always was we would meet at a particular location at six o’clock, plus or minus fifteen minutes. Then Chandra would smile and he would say, “I can be plus or minus, you must be minus.”  

I commented to him that I had been spending a fair bit of time going over background for this examination. Chandra said, “You people.” You always knew you were going to be scolded a little bit when he said, “You people.” “You don’t know how to prepare for an examination. Your committee will not spend more than 15 minutes preparing for your examination. There’s no reason for you to spend more than 15 minutes preparing for your examination.” I suggested that I didn’t see how that was possible.

He said, “Well, you simply have to think about the questions they’re going to ask you.”

I said, “That might be difficult to predict.”

He said, “On the contrary. You take Sam Allison. Allison knows you’re my student, he knows you were working in astrophysics. He knows I, Chandra, have worked on the H-minus ion.” The H-minus ion is a hydrogen atom with an extra electron attached. It is the principal source of the opacity of the outer layers of the sun to emerging radiation, very important astrophysical subject.

Allison knew that Chandra had worked in that field. Chandra said, “Obviously, Allison is going to exam you on the H-minus ion. For example, do you know the binding energy of H-minus?” I gave him an answer, which Chandra corrected, and Chandra gave me about a 15-minute examination on H-minus and he grudgingly admitted that I probably would pass. 

We got to the examination. Chandra called on Mrs. Mayer to examine me first. You know, I’m naming these names and I’m just amazed at the good fortune that I and my classmates had in getting to know the extraordinary people that we were allowed to know. So, Mrs. Mayer examined me and I stumbled through it, albeit apparently successfully.

Chandra then turned to Allison and said, “Sam.” Allison looked at me. He looked at the ceiling. He looked at me. He looked at Chandra. He looked at the ceiling. He looked at me, and he said, “Let us talk about the H-minus ion. For example, do you know the binding energy of H-minus?” 

Chandra and I made eye contact, and it was impossible to avoid laughing. Of course, the rest of the committee is at a loss to know what’s going on. My only course of action was honesty. I said, “Professor Chandrasekhar asked me that question yesterday evening. I told him I thought it was about 7/10 of a volt, and he told me it was closer to 3/4.”

Allison looked at me. He looked at the ceiling, he looked at Chandra; he looked at me. He said, “Oh. Let’s talk about something else. For example–” and then he examined me on alpha decay.

Allison had a nice manner. At a Fermi Institute seminar – this was an interesting process, because the Ph.D. members of the physics community would assemble in the big seminar room in the old research institutes. Allison would occupy an easy chair on one side of the room at the front, and Gregor Wentzel, one of the early pioneers of quantum theory, was in the other easy chair. A young man gave a seminar—and, by the way, this was a kind of Quaker meeting, because Wentzel would turn around and he would say, “Does anyone here have something interesting to report?” Then you had to have the courage to volunteer to give a talk.

So, a young man gave a rather opaque account of recent work on nuclear form factors coming from the linear accelerator at Stanford. Now, form factors are a mathematical tool for describing the shapes of nuclei or elementary particles.

At the end of the colloquium, the young man sat down and Sam Allison leaned forward so that he could face Gregor Wentzel. He said, “Gregor, I’m very disturbed. This was obviously an important subject, and the young man obviously is a master of the subject. But I thought that I should have understood it better than I think I did, because in the 1930s when we were doing X-ray physics in Ryerson, we used to talk about form factors. And all we meant was the Fourier transform of the charge distribution. Gregor, is that what he’s talking about?”

Wentzel laughed and he said, “Yes, Sam, that’s all he’s talking about.” Allison had a way of, I think, being instructive without necessarily being offensive.

I did hear a story. I think it was from Dorothy Johnson. Dorothy Johnson had been Allison’s secretary, I think, at the Met Lab when he was director. She was later the assistant to the Dean of the Division of Physical Sciences, and I think she told this story. Harold Urey was giving a tour of his house to a number of colleagues, and he pointed to the Nobel Prize medal and various things. Then he pointed to another award, which was a fairly distinguished award, and he said he was pleased to have it, but he didn’t think too much of it. Allison said, “But, Harold, that’s the only award that I ever got.”

Harold Urey was a character. That often showed up in comments by my colleagues. Again, he was regarded with enormous respect and affection, but he was also somewhat eccentric. This was recognized.

Again, to be on a campus with all of these icons and you went to a physics colloquium and you didn’t get near the first two rows. The interesting thing from my point of view is that a number of people who subsequently received Nobel Prizes, I had the privilege of knowing before they got their Nobel Prizes. As far as I was concerned, the people who got Nobel Prizes were not necessarily distinguishable from the people who didn’t. It was just an extraordinary Physics Department, which was a legacy of the Manhattan Project that benefited very much from the leadership of scientists like Compton and Allison and Fermi. And from the oversight of a university chancellor like Robert Maynard Hutchins.

Well, there were two generations of graduate students. There was the group that came into the Department just after the war. Many of these, for example, Mark Inghram and Murph Goldberger, had their undergraduate degrees at the beginning of the Manhattan Project. They had worked on the Manhattan Project and they were experienced physicists when they came back to the Department to work for their Ph.Ds.

The Department was challenged to reject applicants. They could accommodate only so many graduate students. They were rejecting applicants who in any other era would have been slam-dunk admissions. That was rather frightening to my generation, which was the next generation along, because we were now in the more conventional mode. The graduate work was simply a stepping stone in my academic career. I did not have a lot of research experience outside that people like Goldberger and Inghram had.

It’s interesting: there are copies of candidacy examinations on file in the library. If you go, say from 1946 to 1952, approximately, they are really daunting. “Design a betatron,” that was one of the candidacy exam questions. “How deep a hole can you dig?” One of Fermi’s questions was estimate the number of piano tuners in the City of Chicago. Well, that’s an interesting question, because scientists have to invent data from time. I mean, there’s an apocryphal story that two young people were stymied with some problem and so somebody said, “We’ve got to go get Teller to guess some data for us.” I mean, Fermi was a source of questions with respect to life elsewhere in the universe. Fermi is famous for the question, “Where is everybody?” He was a skeptic.

Chandra told a story that he and Fermi were collaborating on one of the papers that they published together in the Astrophysical Journal. Chandra wanted to work through the details of a certain calculation, and Fermi said that wasn’t necessary. “We don’t have to discuss that now.”

Chandra was called away for a brief time, and he came back and he found Fermi doing the calculation. He said, “I’ve caught you!”

Kelly: I want to pick up something you had mentioned as you were chatting before we got the camera going, about women scientists. We know about Leona. You mentioned a woman at MIT, and if you could tell something of those times for women. 

Vandervoort: Women in science is a subject with a very difficult history. For example, well, you asked about the lady at MIT. When I was a graduate student, another student, Millie Rife [misspoke: Spiewak], she’s now Millie Dresselhaus, was a graduate student a year or two ahead of me. I think she had done a Fulbright in England and, in fact, did her Ph.D. thesis essentially under the supervision of that mentor. The university is very good at negotiating irregular arrangements.

She married her current husband, [Gene] Dresselhaus—what is his first name, I forget now—but she followed him to Cambridge when he got a post-doctoral appointment. I guess he was a junior faculty member here at the time. He moved to MIT, and Millie was looking for a job. She found something in the Lincoln Labs, and there is a wonderful history where she simply proved her worth to the point that she was appointed first as a professor in engineering and then became a professor in physics. And is one of the MIT university professors, which is one of approximately a dozen most senior professorships at MIT.

Here is this lady who had a certain struggle. She met the usual obstacles. She went to Cambridge as the spouse. “Something has to be found for Dresselhaus’s wife.” That was the problem. It’s interesting, I did the paperwork when the Alumni Association of the University of Chicago conferred the Alumni Medal on Millie a few years ago. My principal resource was a biographical essay on Millie by her husband. That was the most charmingly affectionate bit of biographical writing that you could wish. He was so proud and so honored to be the spouse of this extraordinary lady. She is an acknowledged leader in carbon chemistry in the world. One of my colleagues quoted her, “If you’re a woman in science, one of the secrets of success is to be sure to have your babies on Saturdays.” That was an interesting case. 

Maria Goeppert-Mayer was a very accomplished physicist at the beginning of the Second World War. At the end of the war, her husband, Joseph Mayer, a physical chemist, was appointed to the Chemistry Department and the Fermi Institute. But the university had nepotism rules, so Mrs. Mayer – there was not a position at the university for the spouse.

Happily, Robert Sachs was in a senior position in the theoretical division at Argonne, and he gave Mrs. Mayer a job. She was assigned to be in residence on the campus of the University of Chicago to provide liaison between the Physics Department here and the theoretical division at the Argonne. Another one of these very creative solutions to a silly problem. She was always listed in the catalogue as a “volunteer professor of physics.” Her university title had the adjective “volunteer” attached to it. For all accounts, she was de facto – maybe not de jure, but de facto – a full member, senior member of the Physics Department. When she won the Nobel Prize, the word is there was nobody happier than her husband, Joe.

The Department of Astronomy and Astrophysics became interested in adding to the faculty a very accomplished and distinguished woman astronomer, an observational astronomer in England. The Department began negotiations with her to appoint her to the faculty. Part of that negotiation was that the university would guarantee a staff research position for her husband, a theoretical astrophysicist. When the university raised the possibility of providing a staff position for her husband, the lady simply said that would not work. She argued that her husband, who was fully qualified, should be appointed to the faculty position, and she would accept the research associateship.

As members of our Department, they functioned comparably as full members of the faculty. The lady attended faculty meetings and voted, often in conflict with her husband, on particular matters. That is another example. The couple left; they have had distinguished careers. The husband is no longer with us. So, again, you find ways to cope. I will say that in today’s world, we would almost certainly appoint both of them to the faculty, but our culture was healthy enough that de facto, if not de jure, they were equivalent members of our senior faculty.

There is another example. In 1960, I was just drifting into astrophysics formally, and I attended a summer school on the galactic system, the Milky Way, in the Netherlands. There was a classmate at that summer school, Vera Rubin, a name you might well want to look up. Her husband was a physicist and early in her career she followed her husband as the spouse. When we were together at the summer school in the Netherlands, she was already an experienced and accomplished, opinionated astronomer. Interestingly, the anonymous husband and wife team that I just described were among the lecturers at this summer school. Vera Rubin had an opportunity to begin working with them, and she started working on the observations of and interpretation of the rotations of spiral galaxies. Professionally, as I say, she followed her husband.

She came under the mentorship of George Gamow and got a Ph.D. on the strength of a thesis on structure in the universe, which was a pioneering thesis. Which could only be published in the Proceedings of the National Academy of Sciences, because Gamow was a member. When the members of the National Academy want something published, it’s published. Vera went to work with her mentors in the structures of spiral galaxies and took up that work in collaboration with Kent Ford, where she was employed in the Carnegie Institution. She is credited as being one of the earlier discoveries and expositors of the evidence for the existence of dark matter in the universe. Now, she’s on everybody’s short list for people. She’s getting rather frail now, but she was sort of the same generation as Millie Dresselhaus. I regard these ladies as elder sisters in whom I stand in awe.  

Well, again, an example of a woman who went through that very difficult transition period before we learned to recognize the equivalence of the genders in all the respects in which we should be recognizing that equivalence. Among my bits of good fortune has been the opportunity to know some extraordinary ladies who I’ve encountered in science and I can count as friends or mentors, or colleagues or classmates.

I’m very proud of the fact that the most distinguished current member of the Department of Astronomy and Astrophysics is Wendy Freedman, who was the leader in modern efforts to measure Hubble’s Constant, and the chairman of our Astronomy and Astrophysics Department is Angela Olinto, who is a distinguished service professor. We have been hiring some extraordinary young women, and I think roughly half of our graduate student population is now female, of that order. Some of them are among our best students, NSF [National Science Foundation] fellows, dissertation fellowships, things of that sort.

We’re finally getting it right. We still have a ways to go. We have a long way to go. Women are still a minority on the faculty of our department, but we are now rather even-handed in our treatment of faculty appointments.

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