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Interview of Clyde Wiegand by Bruce Wheaton on 1977 September 26, Niels Bohr Library & Archives, American Institute of Physics, College Park, MD USA, www.aip.org/history-programs/niels-bohr-library/oral-histories/4962
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Family background, early education, and science-technology interests in California and Oregon; Willamette College and radio electronics; contacts with E.O. Lawrence; career as graduate student at University of California, Berkeley, 1942-1949; war work at Berkeley Radiation Laboratory and Los Alamos; security; attitudes toward Trinity test and Hiroshima; postwar political involvement; big machines and general comments on postwar physics.
Today is the 26 of September 1977. My name is Bruce Wheaton and I'm sitting in the Lawrence Berkeley Laboratory office of Dr. Clyde Wiegand. Dr. Wiegand, I'd like to begin by asking about your very earliest recollection of your family. You were born in 1915 in the state of Washington?
Can you tell me something about your family?
I didn't have any brothers or sisters. My grandparents came from the mid-West a few years before I was born. They came clear out to the coast. I guess when they started for the West, they went as far as they could and stayed for a few years at Long Beach, Washington — a little town where I was born. We lived there only a year and then my grandparents and my family moved to Willamette Valley in Oregon around Salem. That's where I spent my first few years. Then my immediate family came to 0akland and I started in the 6th grade at Oakland. I can remember the day of the Berkeley fire very clearly. I think in '25. I went to Oakland public schools through grade school, and then I went back to Salem for junior high and high school and then Willamette University.
I hadn't realized that you were down here. You were here from age three or four until ten or so?
Apparently. I remember going to primary school in Oakland through the fourth, fifth and sixth grades in Oakland. In fact at the Claremont School which they just tore down last year.
Yes. That was one of the pretty ones.
Do you remember why your family moved down to Oakland?
My dad was a ship carpenter and I think that they thought there'd be more opportunity for him in this area. But it didn't work out.
Is Salem on the coast?
No, Salem's about sixty miles inland into the Willamette Valley. I remember when we lived in Oakland. I can remember my first radio set. I was always interested in things scientific. I don’t remember exactly the circumstances, but I see this coil I wound. Some fellow had given me a crystal and we got a pair of headphones. The first station, I think, was KLX in the Oakland Tribune Tower. I can remember driving out East 14th Street and seeing the big letters KGO and learned later that it was radio station KGO.
That was while you were in the sixth grade?
Probably the fifth grade.
Was this a friend that you made this crystal set with?
No. It was a friend of the family. He even had a tube set, at that time. It was probably 1925.
Do you remember how you got interested in crystal sets? From someone in your immediate family?
No, no. They were not scientific at all. My mother was a teacher, elementary school teacher.
Was she teaching down here?
No she had taught in Oregon and when we went back there she taught for many years in the schools near Salem.
Was she the one, generally speaking, with whom you had most of your interactions with as a youngster.
Yes. My mother and I were alone most all the time.
Did she teach you things? I mean, academic or scientific type things?
No. My grandmother was the one that taught me the multiplication table when I was a few years old.
Was she living with you?
No. But we used to visit them very often when we were living in Salem. They lived on a farm about twenty miles from Salem. I used to stay with my grandmother in the summer time, before I was school age. I was probably four or five years old. She's the one who taught me. She probably got me interested in these things. I can remember her teaching me the multiplication tables.
Anything that might eventually lead to crystal sets?
Probably not. They had a phonograph and they thought that was great. They heard about radio. I can remember my grandmother saying "Oh, radio would never come of any use because with the phonograph you can hear people anytime you wanted and after they were gone." But of course that idea didn't last very long and they soon had a radio.
Did they have the radio when you were young before you went to Oakland?
No, I think not. There might have been one in Portland. No, (the crystal set) happened in Oakland. I really don't know why.
Were there other early exposures to things scientific that you can recall? Trips to museums or special discussions that you had with friends or with teachers that might have influenced you?
Yes. I went to an elementary school for a year or so — I don't know' what grade it would be.... a one room school, all eight grades out near where my grandparents' farm was. I can remember the teacher there encouraging me... l was interested in astronomy at that time, learning names of the stars and things like that…
After you came back from Oakland?
No, before we came down here. I must have started the very first grade when I was still back in Oregon and come to Oakland maybe for grades, three, four, five and six. We lived out near East 14th Street. I can remember being interested in airplanes at that time. My dad was living with us then and I can remember he built a model for me, not a flying one, but I was very proud of it and remember it very clearly.
There were quite a few airplanes you could see around the Bay area at that time?
We weren’t far from the Oakland Airport at that time; one would come over once in a while… I’ve been interested in aviation ever since. l have had an airplane now for almost ten years. So I’ve been interested in things mechanical and scientific. I would be apt to be mixing chemicals in the house, little experiments like soda and vinegar making carbon dioxide. The usual things.
Did you ever feel that you discovered something at that time? I mean, according to the values that you had at the time. Were there things that you did with your hands that resulted in a totally new experience for you? Even if they weren't unknown to other people?
No, I don't believe so.
Was any of this ever directed by anybody? Or were you doing this all on your own?
It was all on my own, as I remember. There would have been no direction. My mother encouraged me; at least she didn’t discourage me. She'd put up with the messes and so forth. (Laughs)
It sounds very pastoral, going to your grandmother's for the summers and seeing interesting things, doing interesting things... Do you remember it as a particularly happy time?
Yes, I think that was…
When you were in the schools in Oregon, did they seem different to you? Or was it the same sort of experience that you had had down here in Oakland?
I started junior high school in Salem and for some reason I didn’t look forward to that but once I got started then I was very glad to be there. I guess that was probably where I had my first course in science. I can remember the science teacher now.
Do you remember his name, her name?
It was a lady teacher, Miss Garrison.
What kind of science was it?
Just general science that you'd get in junior high school. And I'm trying to think which grade — it was probably the ninth grade.
Did you do experiments in this class? Did you have a laboratory at all?
I think the teacher made demonstrations and we could probably participate in it if we, wanted to. I don" t remember that at that time but I took much — more of an interest in such things when I got to high school. In that time it would have been grades ten, eleven and twelve. When I went to Salem High, I was interested in anything scientific. It was customary at that time to take the first year — that would have been the tenth year of biology. I liked biology at that time. Then the next year it was chemistry. And, oh yes I liked chemistry too. (Laughs) Then on it came to physics. Oh, of course, I liked that. That was it, the last year. There weren’t any more of those kinds of sciences to take.
Did these all have laboratory work associated?
Yes. The high school ones did.
How did you evaluate your relative interest in the classroom work and the laboratory work at that time?
I think about equal, as I can remember. I liked the laboratory work but I also liked the class work. In chemistry we had a teacher who was, at that time, called a practice teacher.
A training teacher?
Yes. From the Willamette University. He would come over and be the teacher. He wasn't the resident professor of chemistry, but I thought he was a fine fellow.
He was young?
New ideas. New ways of teaching things?
What about the physics teacher?
The teacher was a lady. Her name was Philpot. I think she was probably a pretty good physics teacher. As I remember it though, in most of the subjects I read and studied a year or so in advance of what we would have in physics class. I'd read and study books on my own. Just because I was interested in it.
What sorts of books do you remember reading?
Oh, astronomy books, for example.
Do you remember any of the titles? Or the authors?
No. And then, at that time, I got interested in radio and built an amateur radio station. Incidentally, I can remember when I was probably in about the fifth or sixth grade I'd tried to read an astronomy book that had some mathematics in it. And I didn't know what an integral book was, so when I’d come to this symbol, I had to make up my own sound, that I’d read to myself. But when I look back I think it’s a pity that someone couldn't have told, me what the integral sign meant. I didn’t find out what it was, for many years.
Did you find out things like that in high school at all?
Oh, probably by the time of high school. Yes.
Would they have covered integrals?
Probably, at least to know what it was. High school then, as I remember, was mainly algebra, trigonometry, and geometry.
I know when I was going through high school, it was a relatively new thing that they were starting to do a little in calculus in high school. Before that time that had been pretty well restricted to college.
I don’t believe they did calculus in high school. No. But probably by that time I found out from somebody.
I know when I was going through high school, it was a relatively new thing that they were starting to do a little in calculus in high school. Before that time that had been pretty well restricted to college.
I don’t believe they did calculus in high school. No, But probably by that time I found out from somebody.
In high school, were there teachers or individuals with whom you discussed scientific issues or were you still doing this pretty much on your own? Outside the context of the physics class, did you have any contact with the physics teacher?
No, except in a physics club: we’d take turns putting on demonstrations, things like that. But not outside. We had a part-time training teacher for the physics class, also from Willamette.
Looking back on high school physics, did you think it was helpful? Did you learn things about mechanics and mechanical interaction? Did you actually do some analysis in mechanics or was it this sort of physics course directed toward technological application?
No, it was directed to what we would need to know for college; college entrance requirements and not towards application.
So, you actually did some mechanics; some falling body problems that sort of thing.
Yes, I think so. I was more interested in electricity at that time. That's when I set up the amateur radio station, with the help of a classmate.
Do you feel that there were certain experiences in your youth before you went to college that you missed out on that might have been useful for you? Say, certain things that you knew at the time you would have liked to have but which because of your economic status were out of the question?
Not that I remember. I graduated from high school in 1932, during the Great Depression.' My mother was a teacher, my grandparents had their farm. I’d say the family was sort of average. Probably about average at that time in the things that we could have and wanted. We had cars so that must tell part of the story. (Laughs)
Was your father frequently away?
Yes, practically always.
There was work available at other places?
Yes and the family relationship just didn't work out. So I was with my mother practically all the time.
On the economic business, was it a foregone conclusion that you would go on to college? Or was that a financial problem?
Well, my mother wanted me to go on. After high school I took a year and went to a radio institute in Portland, Oregon, there I studied radio and got a license to be a radio operator on a ship and also in a broadcast station. That would have been in 1932. The spring of 1932 I graduated from high school. It was that fall and winter that I went to this technical school in Portland. Then I started Willamette in the fall of 1933 with my mother’s help. Without her I couldn't have done it.
You went to this radio institute with the idea that you would equip yourself for a professional career in radio?
Yes, But, then jobs, in that field became very difficult to get. Since we were able to do it, it was decided that I should go to Willamette. Later I used the radio license very much. I worked in a radio station in Salem for several years, while I was going to school, So that proved to be a good idea.
Was it a problem financially for you to go to Willamette? Were you able to alleviate some of it with the work in radio stations?
Well, the radio station work came in about 1935 and '36. I had to work when I first went to Willamette. Then remember I got a job to build the fires, in the physics building. I should go back a minute to describe the science building. It had physics in the basement, chemistry upstairs, and on the ground floor, was home economics and some classrooms. It was a stone and brick building. It didn't have central heating; they had heating stoves. My job would be to get down there in time to build the fires in the physics building. I should go back a minute to describe the science building. It had physics in the basement, chemistry upstairs, and on the ground floor, was home economics and some classrooms. It was a stone and brick building. It didn’t have central heating; they had heating stoves. My job would be to get down there in time to build a fire. Say, seven o’clock in the morning, and carry up wood from the basement up to the second floor, easily equivalent to a third floor in a normal building. And I piled this cord wood by the stove, so that the professor and the students could have hear for the rest of the day. I used to get there at seven o’clock in the morning to do that job.
Why the physics building? Was there a reason for that? Or was that just were you were assigned?
It probably came because of the physics professor getting me the job. I can remember that I had a different job sometime later. It was a WPA job; the University had a few dollars to spend on building improvements. The small amount that you’d earn sounds unbelievable. I earned a few dollars around the physics department doing odd jobs. Then I had a job with the Department of Commerce at the Salem Airport as a weather observer. In the evening I would observe the weather and send hourly reports by teletype. I could study then because I needed only, a few minutes, out of each hour to make the observations. I used to work until one o’clock in the morning. That was the year r had calculus at Willamette. The professor was an old fellow. I guess he couldn’t sleep very well and he had class at seven o’clock in the morning. I look back at that and wonder how I ever did it. (Laughs) Seems like kids won't do things like that nowadays but it didn’t hurt. I made it.
So, from the very first days at Willamette you had a connection with the physics department. Is that one that you had forged yourself; had you gone and expressed an interest in the classes, enrolled in classes from the beginning?
Oh yes. There was no doubt in my mind then that I wanted to study physics, and math. I would take extra physics courses at the expense of the required courses. Willamette was a Methodist school, it wasn't very liberal. Those first few· years we had to go to chapel and if you missed a couple of sessions you had a tough time to explain why. You really had to attend chapel in order to stay in school. They were very strict. I remember hearing about a student who played an instrument in a dance orchestra and I think the administration terminated his going to Willamette just for that association. It’s unthinkable in these days that this could happen.
What about the other classes? What sorts of things did you take besides science and mathematics?
I had to take history and economics and some electives. I can remember some times when we’d have a paper that I had to hand in the next period. It'd be doing that in physics class. I didn't miss too much. I think I was keeping up more by outside studies and by being so interested in physics. I looked on the other classes generally as a nuisance that I had to put up with.
Do you think you learned much from those other classes? Wiegand; Yes, looking back at it I’m glad I did. I met graduate students in physics at the University of California. I remember one in particular, I talked about taking economics and he said, "What's that?” Because he had all science and math. I even took a course in law from the dean of the law school. Willamette had a good law school then. And I look back at that as a good idea. But at the time, I didn't like to take history and including a semester of Bible history that was required.
What do you remember about the physics itself? Did the training that you received at Willamette live up to your expectations?
Yes, I think so. I had a good physics teacher. The department had only, one professor of physics! I think that it was all right. But when I came to graduate school I looked back at the physics courses as being, well, sort of minimum in depth as compared to those taken by other students. At the University of California graduate school I was handicapped I think, for not having such a strong basis in physics as the other people in graduate school did. But apparently they had studied just math and physics and didn't have to take other courses. So they had a much deeper and more advanced knowledge of physics than I did when I entered graduate school. On the other hand, our whole senior class at Willamette went on to get their Ph.D. degrees.
The whole class?
Yes, the whole class. That was two of us. As you can imagine, learning physics was a very personal experience among the professor and his two students.
Do you remember the professor's name at Willamette?
Oh, yes, Professor Brown.
Did you know anything about his background? Why was he at Willamette?
Probably he did. I think he told me. I don't remember now.
Did you do any experiments on your own as an undergraduate; they were responsible for putting the equipment together and getting it to work?
Yes. For example, I put together an oscillograph. In those times, we didn't have such instruments and somehow the professor managed to get a tube between the two of us, with the scraps we could get, we put together a crude oscilloscope.
And it worked pretty well?
Yes, for what it was.
You had a display tube?
Yes, it was a regular oscilloscope.
What was the connection between your interests in radio work and your interests in physics? You said that in high school you found most interesting the sections, on electricity. Was that also true in college? Did you see physics as an extension of your interest in radio engineering, or radio engineering as a part of your physics experience?
Well, I maintained the interest in radio but not to the extent that I wanted to make (it my profession). Well, I have to be careful because I did become a professional in radio engineering. I'd worked at the radio station in Salem in the years 1936, ‘37, ‘38, ‘39 while I was going to Willamette. Then, I became engineer for a group of stations in the Central Valley in California. I worked with them for a couple of years.
Was this maintenance of existing circuitry or development of new circuitry?
It wasn't the development of new circuitry. It was the installation and maintenance of rather standard components such as transmitters. We had to make up our own speech consoles (the controls that the announcer used). And I did design some of those. Yes, in that sense, there was some original design. We didn’t buy the ready-made consoles at that time.
Did you actually make them? Did you fabricate them?
You enjoyed that?
An important part of the work.
I liked that part. I always liked to make things. I like to work with my hands. I miss that in what I’ve got into the last several years. (Laughs) Wheaton; But what was, the relation then with this work in physics? How did you see electronics, in relation to physics at that time?
I don't know about the answer to that question. But it must have been about in the last few months when I was at Willamette that I read where the Rockefeller Foundation had granted Ernest Lawrence some money. I think it was over a million dollars to build a giant cyclotron, (the184-inch). Even though at the time I was connected with the radio stations, I knew I was interested in cyclotrons. I realized that they would be an extension of radio and would, for me, unite the idea of radio and physics. At a certain time I had to make up my mind whether I should continue in radio. I had some offers from stations in San Francisco but I decided to drop that completely and go to graduate school. That’s when I came to the University of California in September of 1941.
You began at Willamette in '33?
Yes, it took until the spring of 1940 to graduate because I didn't take full courses, while I was working full time. It took most of seven years to complete the requirements.
Well, I'm very much interested in what you say about having heard about the cyclotron from a distance. Do you remember how that happened? Did Brown mention it to you?
No. I don't recall that he did. At the radio station I would watch the news. If I remember correctly, I even got this news off the teletype at the radio station. I may be wrong but I can visualize yet seeing that piece of yellow' paper come printing out where the Rockefeller Foundation had granted Lawrence the money. And immediately I was interested in building this cyclotron.
You knew what a cyclotron was?
Yes. At least I had a vague idea of it.
Had this been a part of what you learned at Wil1amette? Or had this been something you picked up on your own elsewhere?
I'm not sure about that. I'm afraid that Brown didn't keep up very well with the progress of physics. He was thorough in teaching from the text books of that period and he was an inspiration to us. I don't recall whether or not he knew about the cyclotron. The physics department didn’t subscribe to the PHYSICAL REVIEW. Brown was probably not a member or he would have taken the journal.
You’re talking about 1938 or so that this happened. The cyclotron had only been in existence for eight or nine years and it seems like a, fairly esoteric sort of recent research to be widely known.
Yes, I think that’s the case.
So you decided that you wanted to go to graduate school in order to learn more physics or to become involved in radio circuitry connected with the cyclotron itself?
Not the latter at all. No, I wasn't any more interested in radio circuitry. The radio was a means to work my way through school. Oh, I was interested in it, of course, but then I soon saw that... well, what would I do? I'd have to join an electrical worker's union or something like that. I wanted to be on the forefront in physics and science.
That’s what I’d like to know. How would you have characterized the forefront that you were moving towards before you actually got to Berkeley? Was it a machine that potentially could answer fundamental questions about the nature of matter? Was it the large research effort being given a million dollars by the Rockefeller Foundation? Was it a large concentration of' theoretical radio frequency problems? How would you characterize the attraction that it exercised on you?
The attraction must have been a combination of some of those. I didn't look at it as having any more to do with radio. Although it does have radio frequency. I didn't see it as a connection to that. But I also can't remember that I looked at it as an instrument to probe the secrets of matter either. Probably more like you mentioned: there would be this great machine and many people working on it. Probably I'd have to say that’s what appealed to me. Of course, I'd like to say that it was for looking into the fundamentals of things but I don't think I should honestly say that.
How well was your expectation borne out when you came to Berkeley? You came to study physics on the graduate level with your own personal expectation of getting involved with the cyclotron? From the beginning were you involved with Lawrence's research operation?
No. Not from exactly the very beginning. It was in September 1941 and school had already started when I decided not to go with the radio station and to come to graduate school. I didn't know anyone at the University of California. I hadn't put in any applications. I just went on my own. And the first thing I did was to go up to Lawrence's office on the third floor of LeConte Hall. I walked in and asked his secretary, "could I see Professor' Lawrence." She said, "Well, he's here." She said yes or something like that. About that time he came from an adjacent room and I suppose he asked me what I wanted. I said I wanted to help him build a cyclotron. "All I have is my transcript of grades from Willamette." I brought them along because I didn't have any introduction on or anything. So I just handed those to him and he looked at them a minute and said "You should go ahead and go to graduate school and whenever, you need a job come and see me." And that was about all. He said go and enroll in physics and then come and see me when you need a job. So I went down to Professor Birge's office, the Physics Department office. I think he said something like, "Why are you showing up here at five o’clock in the afternoon? School's been in session for a week." I told him I wanted to register in the school. He could scarcely believe that I'd talked to Lawrence and that Lawrence had recommended it. One of his main concerns was that there’d be a two or three dollar fee for late registration. Why hadn't I put in my application earlier? But somehow he allowed that we could get this fixed up and let me enter graduate school, which I did. I'd been out of classrooms then for a year and a half. Then as I mentioned before came the realization that at Willamette the formal instruction in physics, at least in mathematical physics, was not so advanced. It was probably mostly on my part I suppose. But I remember how I thought, "Oh, golly, how will I ever get through this?" when I went to some of the first graduate courses in physics.
Do you remember what those courses were?
Yes. At least one, mechanics. Professor Lenzen was teaching. I don't remember the other courses right now. That one stands out in my mind. I must have taken about three courses. I lived in a rooming house near the campus and got back into the idea of recalling what I was supposed to know in physics and math and getting back into the course work. About that time I needed a job. So I went to Lawrence and ended up by starting to work in his laboratory on Dec. 1 (1941). Dr. Donald Cooksey was the first one actually to give me an assignment at the old radiation lab. My first job was to come to work in the middle of the night. There wasn't a basement in the old lab but underneath there was a crawlspace of four or five feet. I was to go down there and make sure there weren't fires. (Laughs) And to look and inspect under the thirty-seven inch magnet to see if everything was alright I was sort of an assistant, just a helper around at that time, getting started. But I definitely remember that Cooksey gave me that assignment. On Sunday following that week came Pearl Harbor. I’ve been with the laboratory ever since.
I would like to spend virtually the rest of the time we have on your impressions of the laboratory as it developed and on your work at Los Alamos. Let me ask you a few things about your experiences as a graduate student. How long were you a graduate student at the University itself? It wasn't very long, was it?
Well, I’d say about nine years. (Laughs) You see, I started in September of '41 taking a few courses and working. Then came the war. I worked mostly full time after that in the laboratory. Class work was somewhat secondary for the next year and a half or so. But, until June 1943, I managed to take a course or two while working in the lab.
I see. And then you went to Los Alamos?
Yes. In June of 1943.
And then after you came back from Los Alamos you finished? So you were then working around the thirty-seven inch cyclotron from the beginning, in the fall of '41. If I recall that was just when actual work had begun to convert that machine to the first pilot studies for electromagnetic separation.
Yes. It wasn't a cyclotron even at that time.
It already had ceased to be a cyclotron when you were crawling underneath it.
That's right. However, I did learn to run the sixty inch cyclotron. T was not on the control board there for a very long time, maybe a few' weeks only. So that I did finally have the association with the cyclotron that I’d spoken of. Well, it was all right but I don't think any of us at that time wanted to be career operators of those machines. It was soon after that I got transferred to being a helper around the magnet which was making its first runs on the separation of the uranium isotopes.
This is the big magnet?
Not the thirty seven inch. The other one hadn't been built. It was just under construction. But I can remember it was either Christmas night or Christmas Eve when Bob Livingston was the operator of the thirty-seven inch as amass spectrograph. I was his helper. Other members of the group came in and it was decided that we had run this beam for as long a time as was practical and the machine would have to be taken apart. The vacuum chamber was opened and we all saw the first shiny deposit of enriched uranium.
That was just about Christmas time?
Yes. It was Christmas Eve or Christmas night, one or the other…
And work was proceeding around the clock?
Oh yes, around the clock for sure.
What was it about Lawrence that motivated people to work the way they did? Of course, at that moment the war was an important part of the motivation. But from your own personal point of view, how would you characterize Lawrence’s relationship with the young people that were working in the lab?
Probably it was his great enthusiasm. It was contagious and somewhat forced, I would say. Have you talked to other people? You must have talked to many people about what went on at that time.
I personally have not. But I have read a number of accounts and some of the interviews that have been done with other people. But I'm always interested in individual perspectives on a central issue. Lawrence is certainly a central figure and one would like to understand him from all manner of points of view.
There were stories at the time, I don’t know whether they can be verified, but incidents like this probably happened.
These were stories that you heard at the time? So they would have affected your own perspective?
You asked what made people… what was the drive. I said something about Lawrence's enthusiasm. He showed boundless energy it seemed, and this would certainly settle one's impression. But I think that at times… well, he’d come in after dinner in the evening and see how it was going. It was his tendency to come in and turn the knobs up to overload, up to maximum, to try to get the beams as high as he could. Well maybe, he could be persuaded to stop short of blowing something out. But then if it burned out, he’d say, "Oh, you fix it so it'll go higher next time." He was somewhat of a taskmaster too. There were stories, and I probably was even involved in one of these but I can't absolutely recall. He would say good-night and good-bye or something and walk out the door and he'd be gone awhile and then he'd come back. We were all sure he'd come back to see if everybody was still working hard. I think this happened. He obviously wouldn’t say such a thing and he seemed to have some excuse. But the fellows used to say "well, this is what would happen. But then he would be in his office in the morning so he really did have a great supply of energy, no doubt about that. We hear stories about Edison, the energy such people had, and they surely did. I recall an amusing incident. It was necessary that Professor Segre and I hang a piece of apparatus in the center of a room on the third floor of LeConte Hall. The room was next to Lawrence's office. It was I think, ten thirty or eleven in the morning and we had to drive a hook into the concrete wall. So we started to make a hole for a fixture to hang this apparatus' in the center of the room, Pretty soon Lawrence carne, sort of bleary eyed, to the door and wanted to know what we were doing Segre said in his Italian accent, We’re putting up a hook to hang Hitler." He explained then what we were up to and that was alright. But apparently Lawrence had been working at the lab late the night before and he needed to take a nap. I've wondered if these people were really apparently as superhuman as they appeared or they just had some kinds of activity, like taking a nap (to regain their strength).
What was the relationship as you perceived it between Lawrence's Research Laboratory and the physics department?
I’d been there only a few months and you don't learn things until years later. I think that the physics department certainly supported Lawrence in his endeavors I don’t know when it would have been evident that the laboratory was going to become, bigger than the physics department. But to my knowledge there wasn’t anything serious about what was going to happen with respect to that.
Was, it clear to you at the beginning of your work at the radiation' laboratory that you were doing war related research.
Oh sure. There was an article in CORONET Magazine that told pretty much the story careful as they were about secrets and things. I used to say they might as well put up a neon sign to advertise it.
I hadn’t known about that.
It'd be interesting. You could look it up. It must have been in the fall of 1941.
Before Pearl Harbor then.
About that time. Yes, probably. I don't remember what issue. And I don't remember what happened to it. Somehow these articles weren't followed up. I never did hear anything more about that. But it was obvious to me then that this was what was happening, I think Lawrence went around and asked us privately. I remember he asked me. He said "What do you think you're working on here?" And I said "We're trying to make an atomic bomb." He probably wanted to know where I found out about it but I don't think he asked seriously. He just said "Well, let's not let it go any farther."
At that particular time I think Lawrence and some other people were recognizing that work in this direction had been slowed up considerably by the more stringent secrecy that the Uranium Committee tried to work under and imposed upon the other people in the early planning stages. Perhaps they felt that it had gone entirely too far and was impeding research?
Perhaps. But Lawrence was a stickler for secrecy. He really believed in it.
What else comes to mind about your earliest reaction to the work here at Berkeley; defining physics in a somewhat broader perspective than you had in the past? Let's take as a specific example what we were talking about before; you first came to Berkeley to work on the cyclotron. It was largely an attraction of a big machine or a big research effort rather than that this machine might tell you things people hadn’t known before about atoms. How, did the realization grow in your mind that you were in fact doing what we now' call "nuclear physics" Or "particle physics"?
The cyclotron that I mentioned was the sixty inch. It was being run quite regularly and when I was an operator for it I can remember they were treating patients. At that time, and even earlier, there was a considerable effort for applying physics to medicine. I expect that these were some of the first exposures of patients with tumors to neutron therapy as an experiment. But now I wasn't interested in that or interested in it, of course, in passing but that wasn’t the main interest. I expect that we got swept into the current leading to the war project. At least as far as I was concerned, there wasn't much thought about basic research, Of course, the whole thing was so strongly directed that no one would have any thoughts, of deviating from that program it seemed to be swept into a strong current that was flowing in that one direction.
Did you feel that most of the people you were working with felt themselves to be in that same situation? Obviously nobody was resisting the war effort, but were any resisting the notion that you were plunging ahead with something which was really a technological project and didn't seem to involve very much physics?
I believe though that it did involve basic physics. It's only in retrospect that it was a technological project. On the other hand, didn't Oppenheimer say that we knew most of the answers when we went to Los Alamos, and that we'd shaken the fruits off the tree of basic research and now we must replenish them? In that sense, yes, some of the fundamentals were known. But I think it wasn't all application. It was an opening up of a new subject of nuclear physics. I wouldn't say it was the same kind of application that going to the moon was an application of known engineering principles. It was more on the frontier.
You didn't know if it would work?
No, we didn’t know if it would work until a few months, I guess, before it happened. But it did work. I think that it wasn't merely a technological application, at least in my way of looking at it.
Carol Mills is quoted as saying that at this time Lawrence was proceeding with the electromagnetic separation experiments not so much in ignorance of theory but in spite of theory. Do you feel that that's an accurate characterization of the state of affairs? I’m trying to get a feeling for how basic physics balances off against the real demands of achieving a practical goal. In this case a sizable quantity of U235.
These first experiments that I mentioned were with the 37 inch magnet. The numbers were right there… You knew how many micrograms you could separate in a day with a test machine and so with the next generation of machines you knew the expected yield. By the time we had the 184 inch magnet, even before that, it was known how efficient this process would be. But Lawrence would just proceed. "Well, we need ten of these machines.” We’ll make them. If we need a hundred, we'll make them." I never went to Oak Ridge to see that plant. But Lawrence would just say, "well, if we need a thousand of these machines, we’ll make them.” I never went to Oak Ridge to see that plant. But Lawrence would just say, “well if we need a thousand of these machines, we’ll make a thousand of them.” There was no limit as to what he would imagine as far the immensity of the project. But the theory was there. The measurements had been made. And he didn’t look for the hope of a breakthrough. This was the way it was.
After you graduated from looking for fires underneath the converted thirty-seven inch, what were your next responsibilities in the effort?
I was a helper — a kind of assistant to Dr. Robert Livingston. In the same group were Ken MacKenzie, John Backus, Ed Lofgren, and I’m sure others. I was a helper to them. Later I was given jobs to wire up the controls of the magnet. I liked that kind of work. I had a small room off the 27-ince magnet room where I could do this work. One day Professor Segre came in. I guess I knew his same at that time but that’s about all I knew. I guess my bench looked like an appropriate place where he could lay this stuff down and work on it. And I soon saw what he was trying to do. He seemed to be four thumbs and two fingers trying (Laughs) to wire an amplifier. After I finished my current job, I began watching him. Well, I couldn't stand it any longer and went over and said, "Could I help you with this." He was, oh, too glad to shove it over to me. "You make this." So I went ahead and completed the unit for him. Then some time later, here he came bringing another one. Well this was more in my line of work and I liked it. I kept making equipment for him. Then he went to Lawrence and pried me away from the uranium separation project. This was really a break, as I look back on it. I didn't really care too much about the separation project; it was alright but it was obvious — that it was just going to be a big industrial project. At least it seemed so to me and I wanted to get on to something different. These amplifiers had to do with trying to detect spontaneous fission and measuring the enrichment factor of the separation process. Was it really separating U235 or not, and how much? That was the project being done by the chemistry group. The people I knew among the chemists were Joe Kennedy and Art Wahl. Segre was somewhat of a chemist too. The chemists made the foils, of uranium and Segre had figured out how to use the 6 inch cyclotron to irradiate these foils and tell how much the enrichment factory in U235 was over the natural mixture. That became my new project and I was no longer connected with the electromagnetic separation business.
Was this some of the work that appeared many years later in the PHYSICAL REVIEW?
Oh, that must have been published sometime.
But it wouldn't have been published at the time?
Oh, no. In fact, we never even used, the word "uranium" around the laboratory. You never heard that word even at Los Alamos… That was part of the security. All the sensitive substances went by code names. We never said uranium. That was a no-no. Even in the laboratory, even in the most private (conversations) one never said (that).
That raises an interesting issue. The work that you're doing is not going to be published. Were you personally ever aware of a conflict between the values that had brought you into doing work in the sciences in the first place and the secrecy that was then necessary because of the war?
No, I think that came later. I used to think that a lot of their security measures (were pointless), at least after seeing the publications I mentioned previously. The secrecy people, I guess, did what was natural.
What about fission itself? Had you been aware of fission before you came to the university? There were some reports of that in the press that were quickly stopped.
Well, it was published in the PHYSICAL REVIEW also. I probably wasn’t aware of it when I started. No, I don’t remember being (aware); but immediately afterwards (yes).
That knowledge plus the separation work that was going on in the 37 inch magnet connected in your mind; made it clear that you were trying to actually produce a fission chain reaction in some sense?
Well, yes. And I think it was obvious even to a new student like I was. I don’t remember that there was any question about it.
You didn't spend very much time on the separation work itself?
That would have been some time in '42 that you began other work?
Yes. In early ‘42 in fact I was only with the separation and the cyclotron for a few months. Our lab was in the same building, the old radiation lab. Later, testing these samples became a routine. They kept improving the spectrograph. The one hundred eighty-four inch magnet was about to come on-line. At least we had then many more foils to test. It was in the spring of ’43 that Oppenheimer sent for me one day. I’d expressed a willingness to go someplace else. I don’t recall exactly how it was put. We’d go someplace and try to make this device. So I said I’d go. And Oppenheimer showed me a picture of a building that was Los Alamos Boys School and said, “Here’s where you’re going.” That’s the way it turned out. I guess my first job connected with Los Alamos was to make a list of the electronic components we’d need for a small electronics laboratory. How many resistors, capacitors, tubes, etc., — a shopping list of what we’d need.
Had you had contact with Oppenheimer before that? Had you taken a course with him?
No, I didn’t take a course with him because he was teaching more advanced courses that I wasn’t ready for at that time. In fact I couldn’t understand much of what he’d say in meetings. But I remember one meeting especially. I guess it was the afternoon meeting of the physics department. But I can remember this so clearly. It was probably in September or October of 1941 when Pauli was visiting Berkeley. This was probably my first contact or knowledge of Oppenheimer. This meeting was announced when I was a new student having been here only three or four or five weeks. So I went to the meeting. It was an ordinary classroom but there were chairs and watch what was going on even if they didn’t fully understand. I expect they could participate but obviously this was not likely. Well, at the table was sitting the faculty, including T.R. Birge and William Williams. Pauli was giving his lecture and writing on the board and I saw this younger looking fellow, who was just shaking his head violently, yes, yes, yes. I didn’t know at the moment — but he turned out to be Oppenheimer. But there was William Williams who kept interrupting Pauli. He’d say “You invented these neutrinos, now what are they?” And Birge would try to shush him up and then Pauli’d go on and he’d look over there. He couldn’t believe it. Pretty soon Williams said again, “Well now, these neutrinos, you invented them, what are they?” And he kept bugging poor Pauli. I expect Pauli was used to a more sophisticated attack than that. Birge and other fellows on the faculty were trying to keep Williams quiet. (laughs) So that was my first knowledge of Oppenheimer.
Did he participate in that discussion?
You say that the things that Oppenheimer was teaching were things that were a little advanced at that time; does that mean that in the course of your studies before you went to Los Alamos you had studied quantum mechanics?
No. In fact, I think the University of California was sort of behind the times in quantum mechanics as I found out later. I shouldn't say that. Oppenheimer was on the forefront. What I meant was in the requirements for students.
So you had had classical e and m and mechanics and maybe thermodynamics, statistical mechanics perhaps, maybe some atomic theory?
Yes, and optics. I had optics from Birge, a course in thermodynamics: from Segre. Lenzen taught a beautiful course in mechanics. Later I heard people, they thought that he was too cut and dried. But as I look back at it, I think it was a good course.
So when Oppenheimer sent for you in ‘43 you still hadn't had much contact with him?
You hadn’t worked on anything that he was also working on?
No, no. He was in theory.
He was looking for people to support the general effort at Los Alamos and you appeared to be the person to organize the electronics aspects. Testing equipment, that sort of thing?
Yes. MacMillan was in on that too. Oppenheimer probably gave Ed MacMillan the responsibility. But I remember making out the lists. That was my first job in connection with Los Alamos whether it came directly from Oppenheimer or MacMillan.
You were unmarried at that point. Is that right?
Married in February of '42,
You were just married. Did it seem like a big step to be going off to a Mesa in New Mexico some place?
Oh, I think we looked on it as an adventure. Well, it was obvious that there were going to be these "mad" scientists going to some mountain in New Mexico to make a super weapon, although there weren't very many people who knew that. We couldn't even say the name Los Alamos. We always called it Los Angeles; well, we spoke of it as L.A. and anyone who was listening would naturally assume it was Los Angeles. Then by that time there was sort of a little group formed around Segre with Chamberlain and G.A. Linenberger, George Farwell and me. George Farwell might have come later. But anyway this small group of people vanished from the lab one day and I didn't find out until after the war that people around there didn't know why. In the early days of the laboratory, most people didn't know' about Los Alamos. My immediate associates that I worked with around the 37 inch magnet, when we left, assumed that we were going to Oak Ridge. When they got there, we weren’t there and they didn’t know for, I guess, years.
What were your personal reactions on first coming to Los Alamos?
I’d hate to be specific because then I might prejudice you to leave out other things that I don’t know about. But let's start with your feelings about how you would be living there? Who your associates would be? How fruitful the work would turn out to be?
I already knew pretty much who the immediate associates would be. I don't think I had any idea at that time that it would become such a center for world-renown people from Europe as well as the United States. Our work at the time evolved into the detection and measurement, if it occurred, of spontaneous fission. That was the primary purpose of our group at Los Alamos. However, we could do other kinds of physics. We were fortunate in that we were a research group. Maybe this is why from the beginning it looked to me not so much as an application and engineering as it was more primary (research). I think we were really, fortunate being in the physics department at Los Alamos. There was a very distinct department of physics, and then departments, of other kinds. And ours was to discover all we could find out about fission and specifically spontaneous fission. That was really our primary object but we could do other kinds of experiments too along the same or different lines — whatever that had to do with fission.
Did your group stay together as a research group throughout that whole time?
Yes. It was joined by Martin Deutsch, and shortly after we went to Los, Alamos. By "we" I mean Segre, Chamberlain, Linenberger, Farwell and me. We stayed together the whole time at Los Alamos.
Are there particular experiments, particular things that you did as a group in that period that you recall as being particularly important that you want to talk about?
This is a technical part of the making of this device. As I was mentioning, we were encouraged to make any experiments that we could to learn about fission and one of our primary ones was the spontaneous fission. My main contribution would come through electronics. Earlier I mentioned when Segre was trying to build an amplifier. He was going by a design that had appeared in probably PHYSICAL REVIEW or REVIEW OF SCIENTIFIC INSTRUMENTS of a 1934 amplifier if I remember correctly. It was designed by someone at MIT. People like Segre who were working with electronics seemed not to question it. I couldn't understand that. But here was this design — I can remember it yet — with radio tubes built into compartments with a certain configuration. This seemed to be the way it had to be done. Between 1934 and 1941 there were certainly better tubes available. I didn't understand it. I would have thought that for someone in physics would use the latest electronic design of an amplifier not more than a year or two old. To me Segre’s amplifier looked ancient — as if somebody had built it as a research project when tubes first came out and then this prescription had to be followed. Of course, I didn't build one like it. I started to make amplifiers more like what I thought modern electronics should be. So, my part of the work at Los Alamos continued in that direction. The primary technical problem was to expose as much uranium to an ionization chamber as possible. Uranium is an alpha-emitter and U235 emitted more alphas per gram than ordinary uranium. Plutonium had a higher specific activity by order of magnitude than does uranium. So if we wanted to study spontaneous fission of uranium and plutonium, it was necessary to build equipment that could stand the alpha activity and yet allow the fission pulses to show up. That was our main problem — it called for faster and faster electronics. I can remember the day when we saw the speed increase by a factor of a thousand. This was before we went to Los Alamos. I mentioned that we had built apparatus to measure the enrichment factor in uranium. Well, one of the steps required that you count the number of alpha particles from the foil of uranium. We were using chambers that contained atmospheric air. One has to know that when a charged particle goes through air, for example, it makes a path of electrons and ionized nitrogen atoms. If you are collecting — as we were then — the atom part and not the electrons, it took about a millisecond for these heavy ions (they were the nucleus and all but one or two electrons of the nitrogen and oxygen) to be collected on our collector plate, thereby make a charge on the grid of the first tube, and make a pulse that we could count. I don't know how he happened to be doing it but Dr. Segre read in a German book where they said that the mobility of electrons was about a thousand times that of the positive ions. So he thought we could try that. We thought it had to be very pure nitrogen. When we were doing these routine measurements on the chemistry foils we had chemists around, so they devised a nitrogen purification system. I took one of our regular ionization chambers and patched it up, plugged up the holes, and somehow sealed it airtight. We didn’t have good sealants in those times but I fixed it so we could flow pure nitrogen through it. But before that time in order to count alpha particles, we had to have a quiet room because a millisecond to collect means that the periods of the instruments: would be a thousandth of a second, exactly in the audio frequency range. So any sound in the room would make microphonics and these would register. So we had to hang the amplifiers on rubber bands and put them inside sound proof housings. We had, I think, six of these in a room and we would try to keep people quiet. Well, all of this was a nuisance. So that was one reason why we were looking for some better method. Well, we tried this idea with the nitrogen, we had the chamber with nitrogen flowing through it and I reversed the polarity so that we could collect the electrons and the amplifier would put out its customary positive pulse. We had a three inch oscilloscope. It was a very simple device, (not much better than the one I" d made at Willamette). When we put in our test source of alphas we couldn’t see the rise time of the pulses. Finally with the lights all out, we could barely tell when there was a fast pulse. Our factor of a thousand we gained right there. Well then it was possible to use time constants in the million cycles per second region so that the amplifiers were immune to microphonics and you could even tap on them. (Laughs)
It was a big step forward.
Yes, this was a great step forward for many practical reasons. As far as I know this was the first electron collection in ionization chambers.
This was still in ’43?
Probably in 42.
That was, still in Berkeley?
Still in Berkeley. Yes. That technique allowed us to increase the number of alpha emitting atoms that we could put in the chamber and still measure fission pulses above the background. I later heard at Los Alamos, that some people had collected electrons in boron trifluoride. Whether this was for the same reason and how it happened, I don't know. It was some group working in the East. But at least at the time we did it no one, to our knowledge, had ever thought of using electron collection in ionization chambers. We measured our samples of uranium at Los Alamos and indeed found that there was such a thing as spontaneous fission. It was important to the project because if there were a fission event occurring, that release of neutrons could prematurely start the reaction. It was necessary to know these rates; to know what happened with plutonium. And it was on the basis of measuring the plutonium spontaneous fission that one of the projects at Los Alamos had to be stopped. (Pause)
We were talking about Los Alamos, a little about the kind of personal atmosphere of this, group of people transplanted up onto the mountain; all working toward one integrated goal. Had you ever been in a situation like that before?
Do you think that it was conducive to developing a spirit that pushed things on? Everybody faced the same sorts of problems of living accommodations and isolation. Or were there negative aspects to it too? I'm interested in what that atmosphere was like.
You're asking whether if it'd been, say, near Los Angeles or San Francisco would it have gone better or faster?
I'm just trying to get a feeling for the environment within which this work was being done. Was it totally irrelevant that you were separated so far from everything? And that people were, in that sense, isolated and knew that they had a long term commitment to being isolated in that way? Did it create personal problems? Were there conflicts between individuals as a result of it?
Not that I know of. I think that probably the only slight disadvantage was that it might have taken a day or so longer to receive an order of material but they had such good truck service that I think that it really didn't matter. So the location in that sense didn’t matter. I don’t believe there were any long term contracts. I think a person could quit anytime he wanted, as far as I know. Isolated, yes but the gate wasn't ever closed. It was open twenty-four hours a day and you could drive or walk in and out the gate anytime without asking anyone. This was one of the things that Oppenheimer insisted on. I expect that military people would have liked to have made restrictions, but there weren’t any during the time that I was there, during the war. The isolation was that you couldn't go to a concert or a bal1game.
Was it hard living under those conditions? Were there problems that had to be resolved?
I don’t think so. I was there most of the time during the war. We went to Los Alamos in June of 1943 so I guess I also had a year and a half living on the outside first. But I don’t think there was much difference. We had the same gasoline rationing and we had the same ration stamps. We had about everything that was on the outside. Of course the store was run by the military but the difference between that and an out-side store, I think, was minimum. We had a theatre and we had movies. I don't think there was much difference from any other military establishment.
Was everyone there officially a part of the Army?
No, no. The Army was there primarily to guard the place. There were the MPs. GIs helped in physics and in the program. I don't know now how they got assigned to Los Alamos. They probably were working in the program and got drafted and then were sent back to the program. I remember that I understood that the appeal to the draft board for me had to go to Washington to the President’s office. Roosevelt had to put a stamp on some document some place for the draft boards and the appeal boards. I understood that many of our cases had to go clear to the top. I don't know what the circumstances were for those who were drafted and then sent to Los Alamos. But there were some. There was a barracks that had the GIs and WACs who were secretaries. But they would be secretaries to most of the military administration. The military had to supply the heat, fuel and the lights and the water and they contracted for the buildings and they built roads. Then I suppose if earthmoving projects had to be done that they’d use military machines.
You also mentioned that you and some other people were feeling at each step of the way that there would be some experiment that would show that the whole project was not feasible and that then it would be over and you would go do something else. Do you think that was a widespread feeling?
This is what we used to say. Now of course, looking back at it, that probably wouldn't have happened. If one of the experiments would have said, "no this chain reaction won't go," then there would have certainly been a period of investigating other methods to do somewhat of the same thing. But there were some experiments that were quite crucial that had to do with physics and the fission process itself. For example, if there hadn’t been enough neutrons per fission or there had been too long a time delay for the neutrons to come out. Well, then at least the acceleration of the project would have stopped or slowed down. It's probably like many of our projects; once you get one going it’s difficult to turn it off. But that would be of a political nature.
Did you feel that this, sort of a large group effort was a new way of doing physics? , That this was something really unusual that had never been tried before? This large group of people working on the same sort of problem?
I hadn’t had the experience so I wouldn't have known about that. Before World War II you visualized physics research as being done on a table top or on a lab roll. The large machines changed that picture. That’s a revolution that the accelerators brought on. But at that time it just seemed to be a natural gathering of people.
Under wartime circumstances. Because quite clearly after the war, the whole complex of physics, the whole nature of the field seems to have shifted more in that direction of large efforts. Thirty-three authors to a paper. There are both, a qualitative and quantitative shift there that one would like to understand a little better.
Well, that didn’t happen at Los Alamos I think. The groups were small. There would only be three or four people on a paper of the work that was done at Los Alamos and later published. It wasn’t the great groups of fifty people that you see now.
Is there anything else about that Los Alamos experience that comes, to mind, not available in any written form, that you think it would be worthwhile to record? You mentioned at one point that it wasn't clear that thing was going work until just a few months before the first test. Was that a revelation to you; to realize that all this work was in fact going to be successful? That you really were to get a working bomb out of it?
It seemed to me inevitable from the beginning, the way the work progressed. Each experiment seemed to say, “Go ahead, it will work.” There just didn’t seem to be a question of it. The certainty wasn’t proved by the experiment, but in the few months before the test, it was a matter of guessing at how violent it would be. Not whether something would happen.
And most of those estimates were low, as I recall.
I think on a whole they were probably low.
Were you at the test?
Yes. I remember it very clearly.
What is there to say about that?
Well, there have been so many articles and stories written about it that I don't know what I could add.
I'm primarily interested in your own personal feelings about it.
We were to set up some apparatus to measure the radiation from the gamma rays that would come out. Most of the experiments were diagnostic; if a reaction didn’t go, what happened? So when a lot of our measuring equipment got overloaded or burned out, that was alright. We were pleased with that. That’s what we were doing down there. We had an experiment in a measuring station that must have been about a hundred yards from the tower. We had a station connected by wires out at ten thousand yards. That was the closest that anyone was allowed to be to the explosion. The main groups of people, the high officials, were at the base camp that was seventeen thousand yards from "ground zero." I'm sure you’ve heard the stories. They told the soldiers to lie down and I guess they did and all that, Chamberlain and were at our station at ten thousand yards. We just went out and stood up on a little mound of earth nearby so we could get a real good view of it! We knew that the chances of, any explosion or any pressure wave that far out was very remote. I suppose we joked that it if did, it wouldn’t matter anyhow. (Laughs) To look through we had the glass that they would normally put in welder’s helmets. When the countdown came we were looking at the spot and when the time zero came over the speaker, the sky lit up and we felt the head from it. And I had time to wonder, “It is going to turn off?” because it just seemed to glow quite hot there. “Now is it going to turn off?” And about that time it started to fade away in intensity.” I forgot about the pressure wave that would come later. Sometimes in the movies, on the radio they show a big explosion and you hear the sound right away. Well, it’s the same as lightning and thunder. It must have taken a half a minute to get there. So I was a little surprised when the shock wave came by. It sort of whipped our pant legs but it didn’t amount to much. It wasn’t sharp. It was said that at that distance a barn or other kind of a not-too-steady structure, would have been blown down. It had no sharp effect on our ears or anything. A mild roar.
Was there any after effect of the radiation on your eyes?
No. We had the welders’ helmet glass. Our radiation meters didn’t measure anything either.
What was your own personal feeling about it at that moment?
I don’t recall any special feelings. I think probably because we knew what to expect. In spite of that it was still, of course, an awe inspiring sight, or an awful sight. We had a test. A month or so ahead of time they made a pile of dynamite go off to test some pressure but it just sort of glowed with a reddish color. It was a mild explosion at that distance, didn’t amount to anything. But on the other hand, about the bomb explosion, we’d had many lectures on what we might expect. Even the purple column due to the ionization of the nitrogen of the atmosphere. We saw it as the glowing purple stem of the mushroom. All of this had been calculated and expected…how the dust and earth should sweep toward it. I don’t remember any special sensations.
Well, did you feel as though the job was done? What you had come to Los Alamos to do was finished and that you would leave?
I suppose so because this was in August and I left in January. Right after that there was quite an exodus. Maybe not in the next few days, but in August and September there must have been quite an exodus from Los Alamos. There were many people who wanted to get back to their classrooms, their university work, all of the other work that they had interrupted.
Was it hard for you to go back to being a graduate student after that?
Yes, but I think only because of the time interruption of three whole years, not because of the experience of Los Alamos.
Did the whole group come back? Segre and Chamberlain?
No, I guess Linenberger and I were the only ones that came back. Deutsch was already established at MIT and Chamberlain, and Farwell went to Chicago, and Segre and I came back here.
When you picked up your graduate studies at that point, did you have quantum mechanics?
Yes, I took a course in it but I never have felt very strong in that field. I’m concerned mostly with experiments; I like to know enough theory to work out advance what I think is going to happen in my experiments, and to be able to explain what's happened. I would have expected you to ask about 'my ideas on the morality of the whole affair. Or was that going to come later?
I tend to find that morality judgments of that kind are frequently retrospective. I’m really very much more concerned with what you were really thinking at the time. Most of the people that I’ve spoken to thought “this was a job that we worked hard on and there it is, it works, we’ve accomplished what we came to accomplish, and not it’s time to do something else."
Yes. So many times though we're asked how could we live with ourselves after participating in such a dastardly development. But I think it would have been only a matter of time. It's a scientific observation that when you put together some uranium or plutonium and you treat it in a, certain way, that is what's going to happen. This we can't control or can't have any opinion on. That is the way it is and so to me these questions didnlt quite occur. One also has to remember that many of the people at Los Alamos had relatives who were lost in the war, or in prison in the Orient or Europe, and so there’s this entirely different feeling than what you might think during peace time. I think that this weapon should not have been used on the civilian population. I don't see the excuse for that. Maybe we shouldn't get into that. But how can the United States talk about morality around the world, when practically within a few days of having this weapon, the first thing we did was to throw it on the civilians.
Was that a surprise to you?
No, we knew what was going to happen. Well, I guess we thought we did. How can I say that? We just believed it and accepted it. There was some last minute talk about threatening, and not really using it. As I remember the people that I was associated with and the way things were going, I don’t think we had any illusions about what was going to happen. Because all the arrangements had been made ahead of time. On the morning after the bomb test I met Oppenheimer at base camp. He was walking in the opposite direction from the way I was going, but he paused to say, "Clyde, we have to get some of these over the Japanese cities."
There were proposals, for example, to use it in some public test on a battleship in the ocean.
Yes, but after all you've been training a bomber crew and they have been dropping dummies out of the same type of airplane, maybe the same on for months. Doing exactly what they were going to do. So, I think it was inevitable what they were going to do. Unless Truman would have said no. But that wasn’t the way it was. We were talking about the secrecy and not mentioning that we were working with uranium either at Berkeley or at Los Alamos. After the test, we got back to Los Alamos and it was a few hours before the news came out. I guess Truman announced that the United States had made an explosion. I believe he did on the same day that it happened.
But that was after the actual use in Japan.
Oh, excuse me, yes. The use over Japan. The test had been called a munitions explosion in Alamogordo. When the war time use was announced, we weren’t around talking to each other in loud voices, going up and down the halls saying “uranium!” (Laughs) That word we’d never mentioned; among ourselves in privacy of our labs or anyplace. We never said that word. So when it was said on the radio then we thought, now we can say “uranium.”
Were you involved in any of the organized attempts on the part of scientists at Los Alamos and Chicago to lobby for civilian control? I mean, for what ultimately became the AEC?
No, I didn't take part in the politics of this situation.
Was there much interest in that at Berkeley when you came back?
No, I don't remember that there was.
The Federation of American Scientists?
I don't recall there was much activity at Berkeley. It was on the East coast.
And in Chicago.
Do you read the newspapers of 1942, '43 and '44?
I have read some.
I don’t know, whether you were in this area. I guess it was publicized all over the nation; the story about the alleged spy ring in Berkeley. Scientist X was in all the papers at least in the Bay Area. There where were headlines about Scientist X. Scientist X was accused of spying and there were lengthy trials. This was an interesting part of the Manhattan project.
What was the connection? I'm afraid I know nothing about that.
Well, perhaps it was not brought up in Oppenheimer books. But wasn't there alleged to be a Communist inspired ring in Berkeley to get secrets from the laboratory? Not someone, I guess, from the laboratory. It turned out that this famous Scientist X that was in the headlines — I can see those headlines right now, two inches high in the paper — he was on my Ph.D. committee and one of my professors. I had a course from him. Well, I never did believe those stories that came out about him, about Scientist X. You would find it fascinating if you got into reading about it…I think there have been books and reports. Well, of course, at the time of Oppenheimer what happened here at Berkeley was brought up. For intrigue and things like that, that’s a whole story in itself of which I know very little. But I was surprised to see that Scientist X turned out to be on my examination committee.
Who was this?
Joe Weinberg. I never did believe, and still don’t, that those stories were true.
Things like that happen in war time. People like to have things to believe in. Bring the enemy a little closer to home.
I think so.
Well, did you find things changed in Berkeley when you came back?
Not especially. I came back to work at the laboratory and continued my studies. Then the effort was to get rid of all the war equipment and get that big magnet to work as a cyclotron. That went exceedingly rapidly I believe.
Let’s see, you came back in early '46.
Probably January of '46.
Was there still talk then about making it a cyclotron? Wasn’t it clear that that was not really the way to go? That you had to go to a synchro-cyclotron?
Oh yes. In the meantime, had come MacMillan and Veksler and their principle of phase stability. Well, it was always the big cyclotron. The main thing that changed was that instead of taking about a million watts, it could be a modest system but with the same magnet.
Were you conscious of the shift we were talking about a few minutes ago? The shift away from individuals doing their research to larger and larger groups working with larger and larger machines? Larger expenditures, needs for higher and higher levels of administration and reviews and checks?
I don’t believe that set in quite so early. I think that the era of the so-called “great big physics” was still to come. There was talk about big machines in the early ‘50s. The older people sort of saw this unfolding and didn’t like what they saw. In a sense they used to say “The machines will be running the people instead of the people running the machines.” And remarks of that sort. But all through the ‘50s I think the groups were relatively small. By then some of the largest had come to be as many as eight or ten authors. So I suppose this growth from one, two and three had started; the numbers started to climb. Maybe it has sort of climbed gradually to where it is today.
When you say the older people were not happy about that, how was that expressed? What were they saying?
I’m trying to think of some of the remarks that they would make. You would have to contend with these big machines all the time and you wouldn’t be able to think about physics. It was a distraction.
Hadn’t that been a problem before the war? Especially with the cyclotrons?
Maybe here’s an outstanding example of what could happen…In the sense of people working on the machines and not thinking enough about physics. Artificial radioactivity was discovered a year or two after the operation of cyclotrons had been under way. I would think that could be cited as an example of this apprehension that people felt.
What is the story on that? The switches for the detectors were hooked up so that the detectors would only be on when the cyclotron was on? Whenever you turned the machine off, the detectors went off.
I think the problem was when you turned the machine off the detectors went on detecting. It had made a material artificiality radio-active and this hadn’t been recognized. So something was wrong perhaps with the detectors. In retrospect you don’t understand how that could happen. So I’ve many times wondered what is going on right under our noses that we don’t see. In a few years we’ll look back and say, “How could we have overlooked such effects.”
What is your own feeling about that? Do you think that the changes that you’ve seen, particularly up here on the hill, have tended to further creative research? Or would problems of similar importance have been attacked and solved even without the large expenditures for larger and larger machines?
I suppose it would be said that the big machines are inevitable and a consequence of what we were trying to do. Because the higher the energy, the smaller is the dimension of the particles you can study…sub-nuclear particles. The only natural high energy machines are the cosmic rays and of course those were exploited a great deal. Many of the particles that are commonplace in accelerators were found in cosmic rays and of course those were exploited a great deal. Many of the particles that are commonplace in accelerators were found in cosmic rays. That research still goes on. I think that people are impatient and can’t wait for the events to come from the sky. Whether all of them, the things that have been found out by the big machines, would eventually be found from cosmic radiation, I don’t see how they could. That might be a matter of opinion. If the effort would be put on such detectors then who knows what might happen.
But the inevitable consequences of larger machines are larger expenses, more control over what you’re doing, what you can do, more people waiting to use the machine, more restrictions on the experiments that you might think of doing. Has this been balanced off the successes that have been achieved?
Probably, it has but I really don’t know. I’d hesitate to say that yet. It would be a matter of definition. Personally when it got up to five or six people I decided I didn’t want to be in big experiments anymore so I stayed out of them. To me it was too much administration and engineering, not physics. There are many students, I think, that have hardly seen the machines that produced a computer output for their physics. All they see is the computer paper. That’s a whole new subject.
Is it still physics?
(Laughs) Well, that’s the question, I think. To some people, of course, it isn’t. But to everybody in high energy physics I suppose (it is) or they wouldn’t be in it.
So, you personally felt that the large group approach was one that you just weren't very comfortable with. You wanted to go back and do the sorts of experiments that brought you into the field in the first place?
Yes, with a smaller outlay of people and equipment. Where I could visualize what was happening at each stage of the operation, and where the control over the experiment was rather direct. I didn't have to contend with all the great problems of logistics and administration. Of course, the penalty probably is that I don't make very great big discoveries anymore. But, take for example, the people at SLAC, how many are on those papers? I’ve counted up into the fifties. I wonder if the greatness of the experiment divided by the number of people is as satisfying as some of my experiments where the output wasn't so world shaking but at least I had a personal involvement in all of it.
Well, where do you think physics is going? Are there more people feeling the way you're feeling? Or does it continue to move in the direction of larger machines, higher energies?
For higher energy physics, that seems to be the way. Of course, that's only a small branch of physics. We who are in that field tend to think of it, I suppose, as "the great physics." But I'm sure the solid state people have entirely different ideas and they can point to the "computer revolution" as a very good example. So I think we should consider high energy physics as an important branch of physics. Perhaps the idea that it fits in more with the arts and the culture. Although who knows? I'm asked so many times, "What's going to be the outcome of these big machines that so much effort is being spent on?" And I just have to say we donlt know. But you could have said the same thing about Faraday's experiments also. His work grew into electricity as we know it today.
One difference of course is that Faraday was working with things at room temperature so to speak. He was working with things of a size and with materials that could lead to directly practical applications. What he came up with was something that could be recreated in the scale of human things. What can you do with a billion electron volt machine? You may be able to create something that you can use in some practical way, but the whole procedure is already so far removed from anything that humans encounter day by day, that it would have to be of a special sort of application. Wiegand; Yep, I agree. At this state I wonder what will be the outcome. It "may just be that we put the facts that we’ve known in books and bind them into a nice volume and put them up by the poetry and the rest of the culture. Who knows? Probably very few other scientific people would share this opinion. And it's just speculation. Maybe I’m the only one who thinks that there's a possibility that these investigations could just come to an end sometime. The way it looks is that we might run out of facilities, run out of money. They're considering making a machine ten times as big as the biggest accelerator in existence, well, there’s a limit to that. Fermi said “You could only string magnets around the Earth, which is as big as you can possibly get.”
Now you can go out in space.
Yes, so that doesn’t even hold anymore. But surely the realization is beginning to dawn on people that the amount of material and energy on the Earth is limited, unless somehow the scientific community can come up with a plentiful supply of energy. If you have energy, I guess, the possibilities are unlimited.
It's also possible that if funding is cut down so that you can no longer build a larger machine than the one you have, then you fall back on the machines that already exist. It’s surely possible to make many new discoveries with those machines. Because in the general motion toward higher and higher energies, probing deeper and deeper, many useful and clever experiments were passed over that could have been done in the old machines.
Yes, that’s a way to look at it. But man always wants to climb the highest mountains so this would be looked at as a nice occupation of filling in the gaps and perhaps getting some practical application. But the high energy people who are out on the frontiers don’t look at it that way.
You’ve witnessed a lot of the growth, the early years of this change in physics. To what do you attribute the success of physicists in creating an environment wherein the government, for example, is willing to fund basic research at the level that it had been funded since 1950 or so? What is it about physics, seeing physics as a cultural activity, which has not been true of music or poetry?
I think it’s a misunderstanding. Innocently contrived, perhaps. Inadvertently contrived might be better. If after World War II the scientific people wanted to build a machine. Congress and the newly formed Atomic Energy Commission would agree to it, perhaps as a sort of reward. Also there was pressure to keep ahead of the Russians. At that time, given what had been accomplished in a World War, the scientific people could just about write their own ticket. I suspect that, even now, whether or not the politicians admit it, in the back of their mind may be the idea “Look what these scientists did in the 1940s.” The scientists say, “Oh these big machines, we’re just trying to learn something about nature.” But how can we be sure that something won’t turn up that will make a great weapon?, so we’d better not take any chances and we should fund these operations.” It appears to me that could have been what happened. As soon as there was some question of the public attitude toward scientists then these findings weren’t so easily obtained. Well, it appeared to me now that the politicians are attempting to buy our way out of the energy crisis. I don’t think “crisis” is the right word, but with the society that we have, we much increase its amount of energy. And the scientific people, I think, are saying “really we don’t know how to do it,” There’s no easy way. We’ve looked toward fusion and maybe that will work out and maybe it won’t. I can remember that it was just around the corner since the 1950s and it’s still just around the corner. One more machine, one more machine. I think it’s a very good endeavor and we should keep working on it but it may not come in time to solve the problems which we have at present. Part of the reason the scientific people get support is that, may be that the politicians believe that somehow the big machines will help out. But we really don’t know. Probably the younger generation of people would say “no, that’s no way to look at it. Look at how great this is and what it could do for us. You don’t know.”
Has your professional career been satisfying to you? Has it lived up to what you expected of it when you were a student thinking of going into physics?
Oh, more so. More, yes. Because I never had any idea of places like Los Alamos. Yes.
Well, that’s good to hear. Thank you very much. It’s been very interesting to talk with you.