Oral History Transcript — Dr. Edwin McMillan
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Edwin McMillan; June 1, 1972
ABSTRACT: McMillanís youth and early education (to 1924); undergraduate years at Caltech (1924-1929), influence of Noyes, Pauling; graduate training and molecular beam work at Princeton (1929-1932) with Compton, Condom, van de Graaf; National Research Council Fellow at Berkeley (1932-34) at Radiation Lab with E.O. Lawrence, J.R. Oppenheimer; on Berkeley staff (1934-1940) as teacher and working on cyclotrons, nuclear physics and radiochemistry; war work at MIT, San Diego, Los Alamos (1940-45), Trinity Test; postówar career at Berkeley working on accelerators; Nobel Prize (1951).
Weiner:As I said, Iíd like to start at the beginning. I know just a bit about your family background, that your father was a physician and his brother was a physician.
Weiner:Then I guess on your motherís side there were medical people?
McMillan:Three of Motherís brothers were physicians in Pasadena. My fatherís twin brother practiced in Los Angeles. Also two of my fatherís many brothers-in-law, one in Los Angeles and one in Accident, Maryland. Both Mother and Father came from large families where there were also a couple of dentists. It was a very medically-oriented family.
Weiner:You were born In Redondo Beach but then you moved to Pasadena.
McMillan:Right. I donít remember Redondo Beach at all. The family moved when I was one year old, on October 14, 1908. So the first time I remember Redondo was going there much later. I donít remember it from-it was a very small town at that time. My father had moved to California to practice medicine, and he had met somebody somewhere who told him that Redondo Beach was a good place to start. When he went there, I believe he was the only physician in town, at least one of a very small number. But after he had been there for a year, well, I guess a couple of years, he was persuaded to move to Pasadena where my motherís three brothers were practicing medicine. So he moved there at the time I was a year old. I really spent my childhood and youth in Pasadena.
Weiner:Your schooling was there?
I went through the elementary schools In Pasadena, and there were two of these—one was McKinley School, the other Grant School. Theyíre all named after Presidents. We lived in several different places in Pasadena. I donít know how much of this you want? I was at McKinley 1913-18, at Grant 1918-20. The first place, on Pasadena Avenue, which I do not remember-I barely, barely remember that place. I remember there was a fence in the back yard and a school on the other side so I could watch the kids playing. But we moved away from that fairly soon. I was three or four years old, and moved to a place on what was then called Center Street, now called Del Mar, 747 Center Street. That house still exists. Iíve been down there since. I went down a couple of years ago and showed my youngest son this place. We went in the back yard. We didnít try to go in the house because people were living in it. When my father went to the Medical Corps in World War I, he was sent to Camp Lewis In the state of Washington for his training.
Itís now called Fort Lewis. My father, mother and my sister—I have one sibling, a sister, a year and a half younger than me, Catherine Helen McMillan, born May 10, Ď09, now Mrs. Francis H. Clauser—we all moved up to a small house sort of in the woods near Camp Lewis. It was on the shores of American Lake. I think American Lake is now a highly built up inhabited area. Iíve never been back. But when I was there it was Just a wooded area and there were a few farms, and this particular row of houses where we lived—a clearing had been made for very small cottages, made for people at Camp Lewis, officers, you know. It was private. It wasnít militarily sponsored. It was privately run, but it was inhabited by people who were at Camp Lewis. I remember quite a lot about that. I learned to swim there. Thatís where I learned to swim, in this lake, just a short road from the houses down to the little pier on the lake, and we used to go in there. I also did quite a lot of exploring in the woods around. Perhaps you might say Iíve always been very fond of nature and I like to go out in the forest, on water and so on. This might come partly from that. Maybe itís natural and maybe I got the idea from living in this rather isolated spot. There were a lot of children in this row of houses, and we had a lot of fun together.
Weiner:How long were you there? What ages did it cover?
McMillan:Well, I was born in 1907, and this would be 1918. I think I can get some of these dates better. I donít have exact records with me, but it would have to be 1918. I was about ten years old.
Weiner:How long did you stay?
McMillan:We were there for several months. Now again, as I explained in the beginning, my memory for dates is very poor. It was several months [from June 8 to September 28]. I went to school, to the little country school there, walked for miles to school and back every day. Well, then my father was sent overseas, and he was assigned to a camp in Chillicothe, Ohio for a while. He was there during the big flu epidemic. Meanwhile, when he was assigned away from Camp Lewis, we moved back to Pasadena and got a small house on what was then the edge of town, at 235 South Bonnie Avenue. Iím not sure that house exists. I went looking for it one time and I couldnít find it. Over the years itís been altered or the area built up or something. I didnít find the particular house that I could identify. We went through the flu epidemic there. My father was in Ohio then. I remember some things about that. There exist some pictures of my sister and me with these little flu masks that people wore on their faces.
Weiner:The kind they still wear in Japan.
McMillan:They still wear them in Japan. But people wore them then. I donít think it was any help with the flu, but anyhow, such a picture does exist. My father then was sent to Camp Upton, the place where Brookhaven is now.
Weiner:Yaphank, New York.
Right. From there he was shipped overseas. This is a place where we can assign a date, because he was shipped out and the ship was well out to sea when the Armistice was signed. The ship was turned around to return to the United States and then the order was countermanded. It proceeded on to France. The ship was redirected to France. He was then in Base Hospital 113 in Savenay, France, for several months. My dates are not that great. There was plenty to do. The war was over but the wounded were still coming in, and there was a lot to do. It was a very, I guess, bloody business at that time. So the medical people, their task was not finished. Then Dad came home about the end of July. I think I have some papers if I can find them, his release from the Army, in which I could establish that date. [Discharged from the Army August 22, 1919, at Los Angeles]. Most of Dadís papers seem to have disappeared.
I tried to get as much as I could of that history and didnít find much in the record he kept. I think I have at least one. Now, about what I was doing during this time—while we were living at Bonnie Avenue I finished elementary school and started high school, and that would be in 1920. So I was in the class of Ď24 at Pasadena High School. About that time we bought a house at 387 South Los Robles [on November 17, 1920], which was the last of the family homes in Pasadena. This was on quite a big lot—it was 85 by 195 ft. They built them that way then. Most of my early life was spent there, when I was going through high school and Cal Tech. I entered Cal Tech as soon as I graduated from high school.
Weiner:Let me ask about some of your interests in high school. Did you express any interest in science?
McMillan:I was going to come back to that. I thought that maybe the best thing to do for my own benefit here is to try to get the logistics first, and then I can come back and get the rest of the stuff to fill in. Cal Tech was just a mile from home. Sometimes I walked, sometimes I took a bus. I donít know why youíd care about that. As I told Professor James D. Hart, Iím going to tell you a lot more than anybody wants to know. Youíll have the fun of scratching out large quantities of stuff.
Weiner:The interesting thing is that you donít know what part of it is what we want to know, so you have to tell it all.
McMillan:Of course I donít, sure.
Weiner:The part youíd leave out might be the most important part, you might as well tell it all.
McMillan:That gets me up to Ď24. I graduated in the class of í24. Then I got a fellowship. There was some oil company, I believe, or some petroleum outfit, and I donít remember the name now, that was interested in the use of radioactivity measurements for logging wells, measuring the activity of different layers of rock that come out of the drill hole, I was awarded this small fellowship for one year. So I stayed another year and got a masterís degree at Cal Tech, and developed this method which was supposed to be a field method for measuring the radioactivity of rocks. As far as I know, it never got used, but anyhow I did that.
Weiner:This was for their use, it wasnít something that was in the nature of a publishable scientific paper?
McMillan:It was never published, no. There was a masterís thesis prepared, but it was for the use of whoever paid for it. It was not published research, no.
Weiner:This radioactivity of rock work is what Robley Evans was getting interested in, but on a different basis.
McMillan:Quite so. Itís an interesting parallel there. I donít think thereís any relation between them.
Weiner:Well, he was doing it for Millikanís work to measure background radiation so the cosmic ray work could be standardized. It was completely different.
McMillan:Thatís right. We were unrelated, Robley and I were in the same class I think, or maybe he was in the class ahead of me. We were in a lot of classes together, and I think itís fair to say there was some rivalry between us. You said this was a very competitive class, but Evans was certainly the most competitive one, and I think some of us in self-protection had to be a little competitive ourselves too.
Weiner:That takes you to 1929.
McMillan:That took me to 1929. Then I went to Princeton for my doctorís thesis, which I finished in 1932. Then I came here. Now, I think weíve got the bare bones of the thing with a few dates. Iíll try to go back and tell what my scientific interests were. As far back as I can remember, Iíve been fascinated by scientific things. I think originally it was more the fascination that a kid has for mechanical things. As a kid I had this reputation for taking things apart. I would take clocks apart, and locks. I had all the locks in the doors out and all that kind of thing. I remember, one of my earliest scientific experiments—this goes back to the house on Center Street. At the back corner of the lot there was a garage, a separated garage, and that was my laboratory. My father had some old equipment. The medical people at that time used various electrical treatments of one sort or another. It is not done any more.
McMillan:No, not diathermy. Diathermy has a scientific basis. These were just to sort of generate sparks, you know. I imagine they were—it was a high frequency current, you know, that doesnít hurt you, but looks like something, and applicators and stuff. He had all this equipment which he didnít use. I got that. So I made things out of it. The earliest operating piece of equipment that I remember making was a buzzer. You know, using the principle of the doorbell, in which you have a magnet, and it attracts a piece of iron, and as soon as that moves it opens a contact and turns off the current and then it goes back again and makes the contact and so on, had the magnet of an old auto mobile horn and the thing that was attracted was the lid of a tin can. There was a stick of wood with a pivot to hold this. Then there was just a piece of metal for a contact. This worked, so it would buzz away when you attached it to a battery. That was my first successful experiment.
Weiner:Were you reading something that gave you background for this?
McMillan:I donít remember any particular scientific reading.
Weiner:Some popular magazine or something?
McMillan:Well, there was something of course called The Electrical something like that, those old magazines. I used to get those, but I donít think did at that age. I was around nine then.
Weiner:Thatís what I thought, so it was before youÖ
McMillan:Thatís right, I was about eight, nine, ten, somewhere in there.
Weiner:Did your father get involved with you in these experiments?
McMillan:No. No, my fatherís interests were medicineí He was non mechanical, nonelectrical. I remember sometimes trying to find out some things from him, and I guess being a little disappointed, and maybe you might say I had a little bit of the arrogance of extreme youth, thinking well, maybe I know more than my dad does, you know, that kind of thing. I also remember an unsuccessful experiment which I will now describe to you. I somehow knew that wet things will conduct electricity. You can conduct electricity through wires but also water will conduct, and wet things. The experiment was to make a circuit around the garage, inside the garage, so I drove a lot of nails and got these sort of juicy stalks of some kind of weeds, and laid them on these nails so that they all touched. And with a battery on the one side and this buzzer of mine on the other side—but it didnít work. Thatís how I learned about the fact that things may be conductors, but not very good conductors.
Weiner:Joseph Henry, for example, went systematically through such materials to find out which were conductors and which werenít.
McMillan:Yes. Well, this was at the age of something like nine, and it was not terribly systematic, but at least I knew what I was trying to do.
Weiner:This was a solitary kind of pursuit?
McMillan:This was solitary, yes. Well, I was a pretty solitary guy when I was young. There was nobody else involved in this. I also had various coils that came out of this old equipment of Dadís, which I did make some high frequency outfits out of. I had some bottles full of water for condensers, and an old Ford spark coil for power, the battery and spark coil, and wound coils on a cereal carton, and could make pretty good long sparks. Thatís all back on Center Street. Iím jumping the gun, excuse me. That came later. I didnít do that then.
Weiner:That was high school days?
McMillan:That was high school days, yes. Iím jumping the gun by quite a few years there. The buzzer and the attempt to conduct through weed stalks were when I was in that garage on Center Street. That part is correct.
Weiner:But the coils were later.
McMillan:had coils then but didnít really know what to do with them, I didnít know that much I made sparks but not in a very knowledgeable way.
Weiner:Could you talk about the background? Youíre not sure what you may have read at that stage? But say in high school yearsÖ
McMillan:Well, high school years, but Iím now talking about back on Center Street. The buzzer and weed stalks Iím sure were done there, and that was about the level of sophistication wasnít terribly advanced. That garage burned down some time during that period. I remember that. That was the first fire I remember seeing. The garage burned up completely, and in the remains there was a Stillson wrench, sort of blackened, the wooden handle burned off, and I still have that. Thatís one of my—all my life Iíve sort of been a collector, an unguided collector because I donít collect anything systematically, but Iíve somehow gotten a lot of odd objects. For some reason or other, I like to keep things like that and remember what they came from. That old Stillson wrench, for example.
Weiner:That was from your first laboratory.
McMillan:Yes. Itís out of my first lab, right Well, I donít remember any scientific thoughts at all during the time I was at American Lake. The focus there was more toward the outdoor world.
McMillan:Yes, but not in a scientific way. Iíve never been a real naturalist. I canít go out and identify all the birds. Well, I had nobody to tell me. In the electrical and mechanical things, you can figure out yourself, to some extent, but when it comes to the natural world, somebody has to tell you. Nobody ever did. I learned to swim there, and perhaps thatís the only accomplishment attached to that period.
Weiner:You were growing up...
McMillan:Yes. The real scientific bent took place in high school, and there was a very good teacher there who gave a course in general science which I took. His name was Howard, I think. Iíve got records on that.
Weiner:Grade reports, notebooks, what?
McMillan:I have a copy of a letter which I wrote to his widow at the time that he died, which was much, much later. If I can find that letter youíll get his correct name. No, my mother saved everything and I think she stored away class records. I think they still exist but I couldnít find them offhand, but boxes of stuff Iíve still got. Mr. Howard, and I canít think of his full name now [Bailey W. Howard], was a very inspiring sort of teacher, and he gave us a general science course covering the whole range. A little biology, a little geology, a little physical science, and so on.
Weiner:Would it be chemistry...
McMillan:Chemistry and physics, right. I also did take a course in biology, and I canít remember the name of the teacher. And this general science course. And of course I took all the mathematics that they gave in high school. I always liked mathematics. At that level I found it fairly easy.
Weiner:To what level did it go? Calculus?
McMillan:No, we did not get to calculus.
McMillan:Advanced trig, yes, and advanced algebra.
Weiner:Plane and solid geometry?
McMillan:Well, plane and solid geometry, of course, yes, which never liked very much. The Euclidian style of geometry never appealed to me. That was something you had to do, but I didnít like it very much. I liked more the analytical types of mathematics, like advanced algebra. One thing I remember—I have to watch myself to see that I donít get these things turned around in time but it was during that period and it was in our house on Los Robles that I made these coils I was talking about. It was a fairly decent high frequency outfit. It wasnít polished. It wasnít the kind of thing that you see in shows that kids build, you know, with beautiful polished Tesla coils and so on. It was pretty crummy looking, but it could make sparks several inches long and do various things. Experiments, making a glow inside of a lamp bulb, that kind of thing.
Weiner:Were there science clubs in school, in high school?
McMillan:Yes, there were. This is something else that, when we get back to this thing, I will look up. I do have some of the yearbooks. There was a chemistry club which I belonged to.
Weiner:Would that mean developing different projects, performing experiments?
McMillan:I must admit I donít remember much about it. I donít think that was an important item and I donít remember too much about what we did.
Weiner:So this science teacher made science come alive for you.
McMillan:Yes, this teacher, give him a lot of credit, Of course, my bent was there, very definitely, and I was going to go into science regardless, but I like to give this fellow quite a lot of credit for directing me in a reasonable way, perhaps to perceiving science as science rather than just a bunch of mechanical tricks, mechanical-electrical tricks. I think as a kid liked it because it was fun, and my idea of science is now something that you do and learn, trying to learn new things. I think I got that there. Another rather important influence was the Friday Night lectures at Cal Tech, which had been going on for some time and still go on, I believe. It was a regular institution at Cal Tech, public lectures on Friday evenings, and distinguished members of the faculty would give demonstration lectures on various topics, and remember quite a lot of this. I can even remember some of the demonstrations. They were kind of showmanship type lectures that would make a point, that would have intellectual content, but also have a certain amount of showmanship in them, so youíd see things happen.
Weiner:You saw them happen on a large enough scale and in a dramatic enough way to make an impact.
Weiner:Do you recall who some of the speakers were?
McMillan:Well, Earnest Watson I remember. He always gave the liquid air demonstration. I canít offhand remember any of the others.
Weiner:Millikan himself, did you ever see him?
McMillan:I certainly saw him. Also, another thing I did, toward the end of my high school career, was actually to go down to Cal Tech and wander about, wander into peopleís rooms and ask them questions. I think I was a pretty pestiferous kid. I think I was probably fairly impossible. But I did do that. I talked to them.
Weiner:What was the response?
Oh, they got interested. Theyíd tell me what they were doing. Also during this high school period, and continuing on into Cal Tech, I got into the hiking and climbing bit, and I used to go up onto Mt. Wilson. Several times with some friends Iíd walk up Mt. Wilson and go bother the astronomers. It was a quieter time then. I think if you did that now, you might look suspicious, but usually weíd go up there at night when they were observing and theyíd let you look through a telescope, look into the 100-inch telescope when they were doing a star spectrum and see the star image on the spectroscope slit—just wandering in, you know, unofficially. Weíd walk up there, then come down again at night, walk down the trail at night, make a little lantern with a tin can and a candle, so you could barely see where you were going and not step over the edge. Also I remember climbing some other peaks in that range.
Thatís when I was at Cal Tech. It was while at Cal Tech that I got to know Professor Bowen, Ike Bowen, who was a great climber, and I went on two trips with him, while I was an undergraduate, to Mt. Whitney. The first time we were trying to climb it in winter, which is very rarely done, and we didnít make it. We got into snow so deep that you simply could not progress. Youíd sink in. We had to give that up. Another time we went up in a drier season and did get to the top. I got to know Bowen quite well. Then, another person I got to know very well was also a climber, Sterling B. Hendricks. He is a government scientist. Heís now in one of the bureaus in Washington. [He is Chief Chemist, U. S. Bureau of Plant Industry]. Heís since become an important scientist, a member of the Academy. I see him still. I saw him at the last meeting of the Academy and asked if heís still climbing. He is. He kept it up. I quit.
Weiner:Was he a student with you?
McMillan:Hendricks? No, he was a graduate student. He was about the same level as Linus Pauling, who was a research fellow, and was teaching, a teaching fellow. I took courses from Pauling. I never had a course from Hendricks, but he was also a graduate student and I think my contact with him mainly was through the climbing. I used to go up with him. He kept it up. He became a professional grade climber, the sort of person whoíll make a first ascent of a difficult mountain. I never carried it that far.
Weiner:Quite a few people in science are still good at it. Occhialini, for example. Still climbing.
McMillan:Yes. Hendricks, as I say, is older than I am. In fact, I think—I saw him at the Academy just recently and he said, I think Iím right in this, that he is 70 years old. He doesnít look it, you know. Heís a very husky guy. He still climbs. He goes into difficult places. But he doesnít go alone any more. When he was at Cal Tech, he would put a pack on his back and set off in the Sierra all by himself, and go over some of the high passes all alone, which youíre not really supposed to do. With a man like Hendricks I guess itís all right. He knew what he was doing.
Weiner:This is at Cal Tech—but weíre not there yet in one way, because itís not clear to me, although everything seems to have led up to it, about your decision to go to Cal Tech.
McMillan:Oh, yes. The decision grew out of the contacts I had had with these Friday night lecturers and the contacts Iíd had by going there and talking to people. I donít think any of the people I talked to as a kid were individuals I got to know later. That is, it wasnít that personal, but it was the atmosphere, the feeling of science as a live phenomenon, something that was going to be very fascinating to get into. But I had decided to go to Cal Tech well before Iíd finished high school. Then I took the entrance exams. They were tough entrance exams but I passed them and got in.
Weiner:Did you have any trouble? First, did you have discussions about this in your family? Were they pretty much in agreement?
The family was in agreement that I should do what I wanted to do, but they would have preferred that I be an M.D. The family felt that medicine was the way to serve humanity. Now, they were very high minded people, my parents felt that that was a much better thing to be doing than just physical science. But they never opposed me. It was very clear that they would have preferred that I had followed the medical line, but I never wanted to. I used to say that the reason I didnít go into medicine was because my father, being a general practitioner, in those days was on call at all times. Heíd get called in the middle of the night and heíd go.
Doctors made house calls then. And sometimes when I was a kid Iíd go around with him making calls in the daytime, you know, and wait in the car while heíd go in to see people. And that didnít seem like the life for me. Itís also possible, to be completely honest (Iím trying to be completely honest with you, maybe not really completely but more than I am ordinarily about my inner feelings)—as a kid, I had no confidence in my ability to deal with other people. I was somewhat solitary and I preferred something I could do all by myself. If youíre a medical doctor, then your career depends on getting along with the people. You have to do something, be a public man. That may have been a part of the reason too. That didnít appeal to me. But science, where you could do your am thing—we didnít use that expression then—you could more or less follow your own thing without too much dependence on other people, was what appealed to me. Also, of course, there was this interest which I had, which was a real interest. That was clearly what I wanted to do.
Weiner:I gather you did very well in high school in all your subjects.
McMillan:I did well, yes. I was a good student. Yes. That was part of the problem, I guess, in being—the atmosphere in high school, if youíre too good a student, then you had to be a bad person, you know. Itís sort of a corollary. There was a very small number of people who were both good students and also got along with other people. You were either scholars, who were a little bit peculiar, or you were the popular people, athletes and public figures. You couldnít be both. There were a few who were, but not many. I think the attitude is a little different now, but it was in my opinion a pretty anti-intellectual atmosphere in high school in those days. Even at Cal Tech, you know, with all those highly motivated students, still if your grades were too good, you were a snake—a DAR, Damned Average Raiser. That kind of thing.
Weiner:Did they use that phrase?
Weiner:Lets get into going to Cal Tech. There was no financial problem, just a problem of passing exams and getting admission. Did you get a fellowship during the undergraduate work?
McMillan:I did, and my memory fails me. I did have a couple of fellowships during the time was there. Freshman scholarship was full tuition, senior and junior scholarships were half tuition. Tuition was $250 per year. I also got the Travel Prize. Our family was not wealthy. General practitioners in those days didnít make very much money, but my father got along. We never suffered. We were never poverty-stricken. But we had to figure quite close, and the tuition, as they had tuition there, was I think a real sacrifice for the family.
Weiner:But you lived at home.
McMillan:I lived at home, that made it cheaper than living out. But there was some financial problem. I know my sister went to Pomona College, and she got financial help from one of our rich uncles. So we were—again Iím being fairly honest—we were sort of the poor members of the family. My motherís three brothers, one of them, Fitch Mattison, was very wealthy. He was a highly successful surgeon in Pasadena and had a big estate, was very well off. Sam, also a surgeon, was next, Gene next, I guess, and we were at the bottom financially of these four. My father and his brother-in-law Gene Mattison shared an office. So we always had the tradition of living somewhat frugally, never spending money that we didnít have to, but there was never a feeling of poverty. You were just careful, thatís all, you did what you had to do.
Weiner:And it didnít interfere with your education in any way?
McMillan:None whatsoever, no. I canít claim I worked my way through, you know. I canít be in that honorable brotherhood of those who did because I didnít.
Weiner:You devoted fulltime to your studying.
Weiner:And from what I understand, after the freshman year at Cal Tech in those days, students were selected out into an A section and a B section, with the A being superior.
McMillan:Well, actually there was an honor section from the very beginning—depending on, as I remember, depending on how you did on the entrance exams. There was something called the honor section which I was in as a freshman.
Weiner:Now, when did you make your choice of field to major in?
McMillan:I think that was very early. I think I knew from the beginning that it had to be physics. That was the closest to the things that I had been interested in. Though it turned out that I did do a lot of chemistry, more than most physicists. And some of the greatest personal contacts were in chemistry. There was Pauling, Hendricks, who were chemists. Then I had Ike Bowen in physics, and another strong personal contact in physics in Jesse DuMond. Have you interviewed him?
Weiner:Heís written his full autobiography.
McMillan:I know, heís told me about it.
Weiner:He just sent another installment of it recently.
McMillan:How is it?
McMillan:As an undergraduate the people I remember best are Pauling, Hendricks, Bowen, Jesse DuMond, and of course there are plenty of others that I knew—Iím trying to think really hard to see if I left somebody out. I donít think so. Pauling was the most stimulating intellectually. Heís a very stimulating person. I suppose I might have turned into a chemist but I never did. I stuck with physics, although I liked chemistry very much. I took courses I didnít have to. I took a course in analytical chemistry and a course in organic chemistry that I didnít have to. Everybody has to take freshman chemistry.
Weiner:I had the impression that your initial choice was chemistry.
McMillan:No, thatís not right. People say that. In fact, the fact that I won the Nobel Prize in chemistry—people say, ďOh, you really are a chemist, you started in chemistry.Ē No. There was never a change. You donít have to make a choice in your first year. You donít have to make a choice I guess practically until your third year. But I knew I was going to be a physicist, try to be a physicist, but I did take a lot of chemistry because I liked it and I also wanted to know it. Iím glad I did.
Weiner:Did you take any specific courses with Pauling?
McMillan:He was the instructor in the honor section in chemistry. He was a teaching fellow, a National Research Fellow teaching, but of course to me he was a professor. I knew he was a graduate student, but he didnít look like or talk like a graduate student He was already very mature in his science. Pauling is one of those people who developed very young, had an absolutely mature attitude towards science, and he was a great teacher.
Weiner:The other people on the physics faculty at the time were Bateman, Epstein—
McMillan:Bateman and Epstein were somewhat shadowy figures to me. They were teaching graduate courses. I knew all these people, but I never had a course from Bateman, Epstein, Zwicky, Millikan.
Weiner:How about Tolman?
McMillan:Tolman, I never had a course from him
Weiner:You had most contact with the people at the research associate level, these people we just mentioned or fellows.
Weiner:How about Charlie Lauritsen?
McMillan:Lauritsen came toward the end of my career. I got to know Charlie much better afterwards, not while I was an undergraduate. I knew him but not well. But he wasnít a great present figure to me as an undergraduate. I took some courses—I did take Smythe, not H P. Smyth, but William Smythe, yes. He told me once, many many years later after heíd retired and I was visiting Cal Tech, ďI never thought you were going to amount to much because you didnít do very well in my course.Ē He gave all these tough problems, and you had to do all these problems in electricity and magnetism. Clyde Wolfe was in mathematics. Not a distinguished man but a good teacher. He taught me probability theory.
Weiner:Carl Anderson was...
McMillan:Carl Anderson was one year ahead of me. I knew Carl, but not terribly well. Iíll tell you, I did get to know Carl, though, the last year, the masterís year I took when I developed this radioactive measurement technique. For some reason or other, I got to know Carl Anderson during that last year, and it turns out that heís an auto race fan, and they had auto races at a track in Los Angeles, these midget races, and we used to go to those things. He was a real fan. He knew all the racers and their records and so on. I do remember, that was great fun.
Weiner:He would have been, I guess, finishing up his Ph.D. then.
McMillan:Yes, he was a graduate student then, Ph.D.—I was a masterís student. Next time we come back I can get a lot more information on these things, because I think all I need is to get a name or something and I can fill in.
Weiner:I have a list of people who were there but I think weíve covered most of them. What about Oppenheimer, when did he come down? Did you have any contact with him?
McMillan:Oh, I had met him, thatís all. I think I met him as an undergraduate but I didnít have any contact with him. Mother person I met while I was an undergraduate was Lee Du Bridge. He was on a fellowship there at that time. Alexander Goetz-he died last year—was a strange character.
Weiner:I have a list of people from the years 1929-30ÖAnd at the lower level of instructors, letís say, there was Birchby in math and...
McMillan:I took a course from Birchby. I donít remember too much about it.
Weiner:He stayed there only for...
McMillan:Eric T. Bell, of course, I never took anything from him. Millikan, Sorensen, I knew, I never took any engineering courses. Tolman I knew, Van Buskirk—he was the registrar really. Bowen I told you about. I had close contact with him. Houston—I knew him.
Weiner:Did you take anything from him?
McMillan:I donít think so. I donít remember for sure. Michal, no. Watson, I certainly took courses, he taught freshman physics. Luther Wear, mathematics, I took a course from him. Fritz Zwicky, I already mentioned, who is still going strong, by the way. Heís a remarkable person. MacKeown I took no course. Oppenheimer, I already mentioned. W. R. Smythe, I took his course. Morgan Ward, I never took a course from. Clyde Wolfe, I did. Birchby, I did. Maxstadt, no. But thatís not a total list there. What year is this? Ď29, Ď30? You need an earlier one.
Weiner:Yes, I donít have that earlier one.
McMillan:Who else do I know there? Francis Bitter, Constant, I knew. There were some few I barely remember. Vollrath was working on frictional electricity. Now, Jesse DuMond Iíve mentioned, who has been a close associate of mine. I got to know his family. Lauritsen. And Carl Anderson was there, Iíve mentioned him. Benedict Cassen, a strange guy. I knew him. Cassen died recently. He was close to a young genius. He was from New York—you could ask Rabi. Have you interviewed Rabi?
Weiner:No, Iíve chatted with him but havenít really done it.
McMillan:Ask him about Benedict Cassen. Rabi thought he was a great genius. He was at Cal Tech then. He went into biophysics and became an expert on radiation effects on biological materials, and became a professor at UCLA. I saw a notice of his death about a year ago. He was a strange person. Robley Evans you know about. Archer Hoyt, physicist, got his degree and got a job in—oh, he got a job with some company. He worked in developing a gravity meter, for prospecting you know, to measure the strength of gravity, so as to know something about the density of the rocks underneath.
Weiner:The Western Precipitation Company, the Cottrell Company?
McMillan:No, it wasnít, it was an Eastern company. I knew him quite well. When I was a graduate student at Princeton I went to see him once. But he died very soon. But he did develop this instrument, and if you talk with people who are in geophysical prospecting, they say, ďOh yes, the Hoyt Gavimeter.Ē Itís well known. Charles Lash was one of the people who went on the Travel Prize with me. And heís an engineer. Heís one of the Travel Prize boys. Walter Michels, another character. This is interesting. You really want to know this stuff?
Weiner:Yes, sure, the whole cast of characters comes alive.
McMillan:Walter Michels got his degree In physics and became a teacher. Heís a well known teacher, wins prizes for his teaching.
Weiner:Went to Bryn Mawr.
McMillan:He went to Bryn Mawr, but he was at Princeton for a while. I knew him also there. Walter Michels was a real character. He loved to tell stories. One of the stories I remember him telling at Princeton was how he broke a tooth eating soup. He swore he did. Heíd been outdoors and the air was very cold and his teeth got cooled off, and he took a spoonful of hot soup and cracked it thermally. Mouzon I barely remember. Henry V. Neher, Victor he was called, Victor Neher is still at Cal Tech.
Weiner:Worked with Millikan, right.
McMillan:I didnít know his name was Henry. Heís Victor. Pearson, no. Pugh, barely remember him. Stephen O. Rice—no, I donít know him. Lynn Rumbaugh, physicist, great big guy, big powerful guy who went to some place in Texas. I donít know any more about him. Thorndike was a physicist, I did know him. Johannes A. Van den Akker, he was one of the sort of genius type kids. I have no idea what ever happened to him. Thereís another Wolfe. Thereís three Wolfes here, all spelled the same way—Clyde, Hugh and Karl. Thatís fascinating. Fascinating. We should get these for earlier years [Bulletin of CIT]—I think I still have these somewhere. Who did I know? Bates, I knew. J. E. Bell, I knew. Noyes, Arthur A. Noyes was an influence on me.
Weiner:In what way?
He took a great interest in students. He took an interest in the Travel Prize people and had us all down to his house. He owned a house out on the point at Corona del Mar down near Balboa, big house on the hill, and heíd invite us all down some times. The influence on me, the direct influence, was about what to do for graduate study, and he thought that every student must go to some place other than his undergraduate school. Of course, now thatís common. We encourage that here. We donít forbid somebody to stay on, but we encourage them to—but I donít think that idea had particularly occurred to me till Noyes said that I should go, must go some place else, and he recommended Princeton because Karl Compton was a great friend of his and was such a wonderful man. Thatís why I went to Princeton. I applied to several places.
I know I was accepted at Harvard, Princeton and maybe one other, but I went to Princeton finally. Roscoe Dickinson, I remember—Lacey, chemical engineering, was a sort of character type person, rather sharp. He was a chemical engineer. Sharp words you know and very good. I donít think I took a course with him, I know I didnít, but I knew him. Howard J. Lucas, organic chemistry. I took a course in organic chemistry with him. That was my only course in organic chemistry. I got to know Lucas very well. We became very good friends. I was interested in this subject. Lucas claimed that he could identify almost any organic compound by its smell. Heíd just open the bottle, take a little sniff, tell you what it is. He was not one of the great chemists. You donít find his name in the histories. But he was a good teacher. He knew a lot. Pauling we talked about. Badger I remember.
Arnold Beckman I knew, now head of Beckman Instruments. That was an interesting association there. Linus Pauling and Arnold Beckman, whom I both knew at the same time, were sort of parallel. I guess maybe Pauling was a year ahead of him, I see here. I didnít realize it at the time, but they diverged politically. Pauling became a radical, you know, and Beckman became a great conservative industrialist. Ernest Swift, he was a professor of analytical chemistry. I took his course. Very straight forward sort of guy, not a character. Don Yost, I knew pretty well. He was one of these loner types that was always doing odd kinds of chemistry. He was a very interesting guy and he was always working on something that was very poisonous or very explosive or something, you knowó-he was fascinating.
Weiner:You had such close ties with the chemists. I know it was because of your own...
McMillan:I knew more chemists than I did physicists.
Weiner:What about the other people who were in physics.
McMillan:Letís finish this list while weíre at it.
Weiner:We wanted to get back to that because itís of interest. Unfortunately itís only half the list, I didnít bring the rest of it.
McMillan:Yes, I donít recognize anybody here.
Weiner:Yes, then it goes on to something else. I didnít have the full book. It was from the catalog. I guess itís called the Bulletin of Cal Tech.
McMillan:We can get the yearbook of my year. I have that.
Weiner:That would show the other students and...
McMillan:Yes. It has a short history of the Institute, written by me with a byline, which I guess is my first published—no, itís not my first because my paper with Pauling was earlier. I wrote this history and they put my name in. I donít think I expected them to do that.
Weiner:Were you on the staff of the yearbook?
McMillan:Yes, I was on the staff of the yearbook. I was also on the staff of the Cal Tech paper, what do they call it, THE BIG T. I was a reporter. That always helps me when I meet the press, you know. I say, ďWell, I was a reporter myself once.Ē For several years I was on the paper there. Wrote stories, went around, I even interviewed people.
Weiner:Staff people or visiting lecturers?
McMillan:Visiting people. Not staff, not local people.
Weiner:In effect you were interviewing people when you were in high school, when you went over to Cal Tech.
McMillan:Right, yes. So I had a little journalistic experience on a very small scale.
Weiner:What other extracurricular activities were you involved in besides these publications? Were there any clubs?
McMillan:There were clubs, yes. There was certainly a chemistry club I was in, and—what do we have here? Iíd have to look at the yearbook. I donít remember these as being terribly important to me. These clubs didnít do very much as far as I can remember. They had meetings.
Weiner:Seems to me that students would have a pretty full load anyway, without having a lot of extra time for extracurricular work.
Weiner:What about colloquia that were presented by guests or staff? Were you invited? Did you go?
McMillan:Colloquiums are open, you know. Sure, I went to many of them. I heard some very very distinguished people. They had a lot of distinguished people. Paul Ehrenfest lectured at Tech and I heard him. Manne Siegbahn I remember. Sommerfeld.
Weiner:Yes, Millikan really brought them in.
McMillan:He brought these guys in.
Weiner:I have a list, by the way, of all these foreign lecturers.
McMillan:I believe Schrodinger lectured once. Iíve heard many more—letís see what I can remember. Oh, Raman, I heard him.
Weiner:In these lectures did you get a feeling for a different kind of physics than youíd been exposed to?
McMillan:Oh, very much so, yes. Quantum mechanics was just starting. It first came out around Ď26 and Ď27 while I was an undergraduate, and there were a few people around the Institute who were following this. I must admit, I did not. I probably could have if Iíd had somebody to lead me into it, to get me started earlier. As it was, the first course in quantum mechanics I had was at Princeton. But Pauling was interested in it. Oppenheimer certainly was. But I didnít have that much contact with Oppenheimer. Most of the old line professors there, people that the undergraduates saw, didnít really think much of it, or they treated it as some new strange theory that may or may not be right, but they couldnít understand it and it was certainly not taught. It was not treated as an important thing from the undergraduate point of view, which is too bad. It would have been nice to have gotten into it a little more at the very beginning.
Weiner:Was there any formal course offered in it, that you know of, of any kind?
McMillan:I donít think so. Certainly not for undergraduates. Since Oppenheimer was there I suppose Oppenheimer must have been giving courses in it for graduate students, but I didnít have contact with that. I wasnít at that level, and my one graduate year there was really not very high level either. I canít even remember what courses I took that year.
Weiner:What did you have to do to qualify for a masterís?
McMillan:Pass certain courses, I guess, and present a thesis. I presented this thesis. This was a method—it was written up as a thesis but never published. It wasnít a secret. It just wasnít published. It wasnít as if this were a highly proprietary thing. It was certainly available to anyone who wanted to look at it. The thesis was deposited in the library and anybody could look at it.
Weiner:Getting back a minute to the courses, I see that Epstein was teaching at least in the year Ď29-Ď30.
McMillan:I never had a course from him.
Weiner:Will, I wonder if you would have gotten some quantum theory because he was teaching heat radiation and quantum theory.
McMillan:I had quantum theory, but the old quantum theory, sure. Now, we have a start on this matter of what courses I took. My task is going to be to get what I have together. I have most of these catalogs. I saved them. And perhaps if I dig hard enough, I can find my records, which I told you my mother kept, you know. They were in boxes. And find out what courses I really did take. I feel this lack of specific memory. So many of my friends can say what year, what course they took and what grade they got, every year by year. Iíve never been able to do that.
Weiner:I think itís remarkable if anyone can do it after so many years. I find that the exception.
McMillan:There are a lot of people I know who remember that way. They can remember what salary they got year by year, you know. I canít remember that. I canít even remember my starting salary as Instructor at Berkeley. [It was $1800 per year.]
Weiner:You got involved in the radioactivity research. Had you had any courses specifically in that area?
McMillan:Oh yes. Radioactivity was covered in a course which I think was called modern physics, something like that.
Weiner:Can you remember who handled that? Thatís something that would be good, to find out what textbook they used.
McMillan:I do not. I do not remember that. I knew about radioactivity, but this specific problem of measuring the rocks was something that—there was a method that had been used in the laboratory. My task was to develop it so that it could be used in the field, so it would be portable. The method is, you dissolve the rock. You grind it up, and then you use some flux, and what flux you use is sodium carbonate, and you put this in a closed crucible and heat it to a bright red heat, and then your carbonate reacts with the silica and the whole thing liquefies, and the radon gas comes out. Carbon dioxide gas is emitted and carries out the radon, and then you bubble this through a tube full of something to absorb the carbon dioxide, then you pass this radon—air containing radon—into an ionization chamber, with an electroscope, and you measure the rate of discharge. That tells you how much radon came out of that rock. Then from that you calculate how much uranium was in the rock. That was the method, really pretty simple.
Weiner:A good deal of chemistry in that, as much of radioactivity was chemistry.
Weiner:What kind of detection instruments did you have?
McMillan:A gold leaf electroscope. I looked up a place that sold gold leaf in town and bought some gold leaf. I actually saw this fellow beating gold, which is quite a process, the old style gold beater. I suppose they still do it the same way. I went to his shop and he showed me how they make it, and I got a little piece of it and made my own electroscope.
Weiner:For example, was that paid for by the fellowship?
McMillan:The gold leaf? I donít think so. The apparatus of course normally is supplied by the Institute. I didnít pay for that. I canít remember whether I paid for that piece of gold leaf myself or not. It doesnít cost much, you know. You only need a little bit of it to make an electroscope.
Weiner:So it wasnít a question of pulling one off the shelf.
McMillan:No, no. Oh, no. No, the equipment was made in the shops there like all research equipment. The electroscope—not the gold leaf—you do that yourself. You canít buy those things.
Weiner:Let me jump back to earlier research involvement which resulted in the paper with Pauling, where youíre the first author, if that means anything, unless it was just alphabetical order. The title was ďThe X-ray Study of Alloys of Lead and Thallium.Ē
Weiner:It was published in a chemical journal.
McMillan:Right, the journal of the American Chemical Society.
Weiner:Whatís the origin of that research? First of all, you were an undergraduate.
McMillan:Pauling had the idea that undergraduates could just as well start research, as undergraduates, and in this section which he taught there were several research projects that he suggested. He gave a list of possible things that people might like to work on. And this one appealed to me. He suggested it. I believe mine was the only one that finally got done and published. I canít remember what the others were. Some other undergraduates started on various little researches of that kind, but as far as I know never got finished. I started it then. Then I worked on it—it was published in Ď27, though it was started perhaps in the sophomore class. That makes the timing about right. The reason my name is first is because I did all the work, you see. He suggested it and he counseled me but the actual manipulations were done completely by me. I made all the samples, put them in the tubes, took the Xóray pictures, measured the pictures and I wrote the paper. The words are my own. So I think it was proper that my name should be first. I canít recall there was any dispute over that.
Weiner:No, but you were an undergraduate publishing with a...
McMillan:Well, I suppose he could have said, ďI thought of the problem, I want my name first,Ē but he never did that.
Weiner:Thatís what I wanted to know. Did it fit into some large research project of his own at the time?
Weiner:It was just something that he thought would be good for undergraduates.
McMillan:His general interest then was crystal structure. X-ray analysis of crystal structure, and he was into that in a big way at that time. He already had quite a lot of crystal structure studies going on already, and this was a little anomaly which appeared in the published literature on what we call a constitution diagram of this system of lead and thallium, that had a shape that was unusual and unexpected and unexplained, and Pauling thought it would be worthwhile looking at the crystal structures for these various alloys of different compositions. You know, you make up different proportions of lead and thallium, in a series, and Iíll show you—you want to see that?
Weiner:Yes. You have a reprint of the paper?
Weiner:Maybe we shouldnít interrupt this.
McMillan:I have reprints of everything I ever published.
Weiner:Thatís something I want to talk to you about. Anyway, that was a paper published in 1927. Were there any other research projects as an undergraduate? On your own?
McMillan:There was another thing I did in physics, which was in a little different category, in that it was not possible to lead to a publication, but experimentally it was very interesting. In this course in physics which—damn it all, I canít remember who the teacher was. It may have been E. C. Watson. I have an awful memory for that. This was in the top section of physics—he set students to experimental tasks, which were essentially to repeat known experiments. That was done by teams. He set us up in little teams, and somebody did the Millikan oil drop experiment...
Weiner:Bowenís class did that, I know he told me. There were three terms and twoÖ
McMillan:Well, then it was BowenÖ
Weiner:Öthe third term would be the experimental one, and he mentions specifically such things as... McMillan...then it was Bowen, all right, then it was Bowen. The one I did was again X-rays. That seems to have been a consistent interest of mine, to get the X-ray spectrum of something, by using the rotating crystal method. You have an X-ray tube and then you have a slit, youíve got a beam of X-rays, and you have a crystal that rotates back and forth, and then a photographic film. As the crystal rotates through the proper angle, then the crystal reflects and you get a line on the film. Every line of the film gives you the wavelength of some particular X-ray emitted by the tube. So this is a fairly elaborate experiment to set up, and we werenít given any equipment except what we could sort of scrounge. We could go into the old stockroom and scrounge stuff. We werenít allowed to order things out of the shop. We had to do it all ourselves. And we set this up. We built a lead box to do this in because you donít want the X-rays escaping into the room, you know. So we built a lead box, and we built the rotating thing. I canít remember which part I built. I think maybe built the lead box. Anyhow, you have to have a motor that runs a cam that wiggles the thing back and forth, and then for the X-ray tube we had an old tube that we found, one of these old, what they call gas-filled tubes, you know, with a cold cathode.
Weiner:I know those old things.
Yes. You get your electrons, get your discharge from residual gas in a tube. It has no filament. And an old induction coil—one of these things thatís in a box so big, built like a piano, beautifully polished wood box, two big insulators coming up. We ran wire from this thing, this tube which was in the lead box, and we had an electrolytic interrupter, which was a glass jar with some lead plates in it, lead and aluminum plates. It made a hideous racket when it was running, and the—we got this whole thing going, and we had lots of problems with it. One time the hydrogen and oxygen produced in the interrupter got ignited and blew the lid off it across the room.
I remember that. Finally the X-ray tube got overheated, and the anode melted and dripped through the glass tube, ruined the tube, but by that time we had enough exposures, so we got our pictures. So that was our experiment. You canít publish that. That was certainly with Bowen. And who was with me? It was, I think, Russell Raitt who was with me on that and one other guy. [Raitt is now Professor of Geophysics at the Scripps Institute of Oceanography.] I think there were three or four of us in on that team. That as I say was not publishable because its just a repeating of some classical experiment. But it was a good experience. We learned a lot, about how to make do with cobbled up equipment, because everything we had was scrounged or built. Nothing was new or nothing built in the shops for us. They had the great idea then that all students must learn how to make equipment. We all took shop practice. We all took—we took a certain amount of machine shop practice. So we did our own machining.
Weiner:Yes, I was curious about that.
McMillan:We also did glass blowing. We learned glass blowing.
Weiner:So there was no tradition of a system where, if you wanted some thing, you had to wait and try to get it from some glass blower. You did your own.
McMillan:Thatís right. It was much more that way then.
Weiner:This was the research then, the paper with Pauling and this other X-ray experiment that was more of an educational one. Let me ask on another line about the Travel Fellowship, before I forget—you got that in your junior year?
Weiner:And did you take it then?
Weiner:So letís go on that story. As I understand it, it allows you to go off for a long period of time, and youíre supposed to work very hard learning on your own?
McMillan:We left in...
McMillan:There were eight of us. Usually they gave two, but that year they gave eight Travel Prizes. They said there were so many people about equal that they couldnít leave anybody out. I think there were three of them who were a little bit ahead of the rest and got more money than the rest of us. Evans and, I think, George Harness; and I were at the top, and we got $900. I do remember that.
Weiner:For six months?
McMillan:As a matter of fact, I kept a record of that. I spent $1375. Itís interesting, amusing for me now, looking at the record I kept, how meticulous I was to record everything, which I certainly donít do now. Iíve really degenerated. I recorded everything I spent, you know, and kept these accounts, so I wouldnít run out of money, and itís all down. I have the record here.
Weiner:Did you go off together as a group? Evans went the following year.
McMillan:Evans went the following year. [Interval] The group was still eight people, however, because Firth Pierce joined it, traveling on his own funds. He was a very ingenious guy. He was finally—he was with the government, and the kind of thing he did was design extremely elaborate mechanical devices, like bomb sights and stuff like that. Much later when I was at San Diego during the war working in under water sound, I saw a fair amount of Pierce because he was doing some work for us, whoever he was with, and I saw some things he did—the kind of Rube Goldberg stuff, you know. Heís now retired.
Weiner:Let me put something on that I didnít put on the tape before while you were writing it...
McMillan:Of all those people, the only one I still have some contact with is Firth. I still at least send him Christmas cards. We communicate about once a year. But Firth was a great associate of mine in a lot of the exploring type things we did. We did a lot of car-camping in the desert and so on.
Weiner:Let me run through the list now: yourself, Charles Lash, George Harness, Albert Lombard, Joseph Schweinfest, Kenneth Solomon, and weíve been talking about Pierce.
McMillan:And Robert Coulter.
Weiner:Now, I think it makes an interesting story to know about the young men, going off, so Iíd like you to tell it from the beginning.
McMillan:Well, Iíll tell you, my diary, which my wife has—my wife got the idea of writing a biography of me, and sheís started now, and you will be competing. Sheís only gotten a little bit done so far, and she wanted this diary. I can get this, Iíll get a transcript of it. In fact, something Iíve been sort of wanting to do for a long time is to collect together stuff Iíve got. Iíve kept a few diaries of trips Iíve made. You can have them then. What I want to do is get them typed up. Theyíre just in manuscript and theyíre not even all in one place. Iíll have to do a little searching to find them.
Weiner:Well, If youíll do it—the point is, if the bulk of your papers...
McMillan:The bulk of this is not great, this kind of stuff. All the papers, you take the official papers, the bulk is colossal and uninteresting, except perhaps to historians.
Weiner:But the sort of project you were talking about before, those papers should be preserved here. Thereíll be portions of things that Iíd like very much to have, just as youíve mentioned now, which would be excellent as a supplement to what weíre doing. Letís...
McMillan:We went to Europe. We all started off in the spring.
Weiner:This would be Ď27.
McMillan:Ď27. We started off in the spring, before the end of the term actually. We got one quarter off. Actually the year is divided into four equal parts, three of which are your three terms, and the summer. They didnít give summer courses then but it amounted to a quarter system with first, second and third terms. They let us off the third term. We took off in something like April and we came back in September. As I say, we—at least I—spent on the order of a thousand dollars. Life was cheaper then. But we also traveled in very economical ways, you know. We all went third class or fourth class on the railroads, saw a lot of life that way—you really did. Riding fourth class on a Spanish train was always—with little kids getting sick all over the place—really something.
Weiner:Was it a prescribed itinerary?
McMillan:There was a sort of itinerary that had been planned, but it wasnít very firm, and we never stayed together very long. We all went over together of course, we went over on a boat—we went over on the Carmania. And we had a rough passage. We had a big storm on the Atlantic that year, and actually one of the big spars came down and broke a hatch cover, and there was water running around inside the ship. I had always sworn that I would never be seasick. I said, ďSeasickness, itís all in your mind, you know.Ē But this made a liar of me. Itís a contagious disease, I discovered. You go down the passageway and a lot of people have been sick before you and you smell that plus the paint smell of the ship—it gets you. We didnít stay together—Iíll get you a copy of that diary. We were together only a few days and then we scattered all over the place. For instance, Firth Pierce and I went off through Spain. None of the others went to Spain. We wanted to go there, so we went from north to south in Spain and across to Tangier, so Iíve been in Africa—itís not much of Africa but itís part of it—then met a Japanese boat, the Haku san Maru, which goes around the world. We picked it up at Gibraltar and landed at Genoa. And we rejoined some fraction of the party in Italy. Then in one part of the trip I went off all by myself. I went down to Vienna and Budapest alone. I knew some people there. So, there was really no fixed itinerary.
Weiner:As I understand this, the aim of it was a broadening cultural experience.
Weiner:It wasnít a scientific tour.
McMillan:No. There was some sort of gesture that maybe we would stop at Munich and take in some lectures at the university. I actually did take in one lecture at the University of Munich. My German wasnít good enough to really absorb it, but I did go. I heard a lecture by Willie Wien. Then, letís see, I guess most of us came back together. I think some of them had deviated and came back other ways, but at least most us—youíll see in my diary—we came back on the Transylvania. Countries I went to—well, England, France, see if I can get this, I wonít try to get the order—England, France, Holland, Belgium, Germany, Italy, Spain, Tangier in Africa for one day, Austria, Hungary, Switzerland. [Also Wales and Scotland]
Weiner:Not much you left out.
McMillan:I donít know, we were real tourists. We moved fast, and we were young and strong. I wouldnít want to do it that way now. Carried our own bags. See, we were very careful of money. We carried our own bags. When a bunch of tourists would arrive, weíd be the ragtag guys carrying our own stuff and fighting off the porters. Theyíd swarm around you. They donít so much now, but in those days, in a place like Spain or Italy as soon as you come in youíre surrounded—little kids begging and wanting to carry our bags. Weíd fight Ďem off and carry our own.
Weiner:In Milan the railroad station still is like that.
McMillan:It still is, I see. Most of Europe though has sort of gotten away from that.
Weiner:Did you have to report, write a report when you came back, were you responsible for...?
McMillan:We never did. Oh, we were supposed to give a talk. Everybody gave a little talk, sort of a public speech in Culbertson Hall, that just got torn down. We all gave a little short account of some highlight. I forget what my highlight was. I did some mountain climbing there, I climbed the Matterhorn and the Zugspitze, the highest in Germany, the Jungfrau, Scafell Pike—the highest mountain in England—I tried to find the high points. I had planned to go up Mont Blanc but did not succeed because the weather was bad. It was not the right weather and we couldnít wait. I had planned to climb that. I planned the Matterhorn, and we just barely made it there. The weather got bad the next day.
Weiner:A busy five months.
McMillan:We did a lot of walking. Firth Pierce and I particularly—we did a lot of walking. Some parts of the trip, weíd somehow send our bags around and then walked. I walked from Switzerland down into France for instance, over—the pass we walked over was a two day trip from—Iím trying to think of the names of places now. We went down to Chamonix, we took a long walk through the Alps down into the Rhone Valley, and we took a long walk through the Lake District of England, sending the stuff around by train, then walking through and picking it up at the other end. It seems to me when I look back, I donít quite see how I did all of that, but it was fun at the time.
Weiner:The only responsibility during that time was to be a tourist, essentially to learn.
Weiner:Itís an unusual kind of arrangement.
McMillan:Yes, it is.
Weiner:I assume they felt it would have some effect on broadening you and on maturing you. A difficult question to ask is, did it? I assume that the experiences were...
McMillan:Well, I think it did. Yes, I certainly do. Yes.
Weiner:Making decisions on your own.
McMillan:I think for one thing it gives you a little confidence. Once youíve fought your way through some of these little places, like the little places in Spain where we went, in very primitive circumstances—the class of accommodations we were staying in and the class of transportation—and figuring your way through all the national boundaries and customs and so on, and taking off alone as I did on one part of the trip. I had the feeling after that that I could go anywhere I wanted. I think it does give you a lot of confidence. Any hang-ups of traveling I get into now, I can always say, ďWell, Iíve seen worse.Ē But when I did get back to Europe again, which was much later, it seemed familiar to me. Iím used to being in a place where I donít understand anything. In Hungary of course the language isnít even Indo-European, so the words donít even look like, our words. And this doesnít bother me.
Weiner:When you returned it was your senior year, and I think weíve covered the courses, the research involved, and I think the next subject is the Princeton story, unless you have another suggestion. [Interval] Let me start up this machine again. Weíve just taken a lunch break. Before that we said weíd talk about Princeton. You mentioned that it was on the recommendation of Noyes at Cal Tech that it would be good for you, or anyone for that matter, to take an advanced degree at a different institution than the one for the bachelorís degree. In this case different from bachelorís and masterís. And he specifically, in this instance, recommended Princeton because of his ties with Compton.
Weiner:But it seems to me there are other questions there. Wouldnít the reputation of the institution, the type of research problems being pursued play any role in determining your decision?
McMillan:Yes, by all means. The personal factor is only one. There were at that time several departments of physics that had a high reputation. Princeton was one, Harvard was one, and there were others, all having good reputations. Iím sure that Noyes was aware of these factors too, but he particularly spoke of Karl Compton as being such a wonderful man. I did apply to Harvard and Princeton, I think also one or two other places, and was accepted at both Harvard and Princeton but decided to go to Princeton.
Weiner:Was there any fellowship involved?
McMillan:I donít remember for sure. Iíll look that up. [I had the James W. Queen Graduate Scholarship, at a stipend of $500 for the academic year 1929-30.] Another person at Cal Tech I knew, Bob White, and I drove across the country on this occasion. This was the first time I drove across the country. We had an old Essex, a miserable type of motor vehicle which belonged to Firth Pierce, and we had many adventures on this trip. I may some time come to that, but itís not really part of the story. The adventures mainly being getting stuck, flat tires, failed generators and similar things. When we got there, we said our tires had patches on the patches, which was true.
Weiner:This was summer?
McMillan:This was in the fall. We arranged to get there in time to register. White was going to Yale and I was going to Princeton, and we ended up at New Haven and he left me there, and I went on down to Princeton. Firth Pierce was in Europe, another trip to Europe, and was going to pick up his car when he came back and drive it across the continent. Complicated. There were always complicated logistics involved in things like that. It was a great experience to drive across the country in the time when there were relatively few paved roads except in cities. One had to fight gravel roads, all kinds of things.
Weiner:How long did it take?
McMillan:There my memory is not that good. It was something like two weeks.
Weiner:Still that must have been pushing it.
McMillan:We were pushing it more or less, oh yes. It may have been three, between two and three weeks. [It was September 8-25.]
Weiner:When you arrived in Princeton, had you given thought lb what you might be doing there, the particular line of research, special interest?
McMillan:No, I had not. It was to be physics, of course, and with—what I did was to go around to various people in the department who had researches and were looking for graduate students, to choose a problem for my thesis. I got started with this fairly early in the game. I also registered for courses and all that, and Iím not going to try to remember what courses I took each year. It was just sort of the usual thing graduate students do, making up for the deficiencies in their undergraduate training. Quantum mechanics, for example.
Weiner:I would like to know who taught that.
McMillan:I had two courses, I had it from Condon and I had it from Wigner. I remember I took that two times. Theyíre both great teachers. The kind of work that Karl Compton was doing was then called electrical discharge through gases, would now be called plasma physics, is very fashionable now, and was fashionable then. Itís a field that has gone on for a long time. But I didnít see any particular problem that I wanted to work on in that field. There was also some optical spectroscopy which I didnít want to do. What I ended up doing was a molecular beam problem. I think the simplicity of the molecular beam method appealed to me. The person I started to work with is a man who is no longer at Princeton, Charles Thomas Zahn. He left and is I think now at the Bureau of Standards. I started my thesis work with Zahn. His own work was in the measurement of the electric moments of molecules by an electrical method, by measuring essentially the dielectric constant as a function of frequency, frequency or temperature, something like that, temperature I guess. But this was closely enough related to what I wanted to do, which was a molecular beam experiment to measure the electric moment of molecules directly by deflection in an electric field, so I signed up with Zahn as my thesis supervisor.
Weiner:What gave you a feeling of interest in this problem? You expressed the simplicity of working with a molecular beam.
McMillan:Yes, I think the simplicity of working with a molecular beam probably appealed to me. Plasma physics is—was complicated then, it still is and always will be. When you have ionized gas youíve got all kinds of things happening all at the same time, and itís a complicated system. This has never appealed to me. I like those kinds of science and those parts of science in which one can get a fairly simple system which you can understand. I think thatís probably—I canít really say exactly everything I thought at that time. That was way back.
Weiner:How did you identify a problem? I understand the class of problem and the technique, but was it something from the literature that made you realize that this was of interest?
McMillan:I think itís probable that Zahn had this idea himself. Itís probable that when I talked with him he said, ďIt would be interesting to measure these things directly.Ē He was measuring them by the dielectric constant method, which is indirect and involves the fitting of a certain formula to a certain set of measurements. It probably came to him. I think it will be impossible to find out now. I canít guarantee whether I thought of it or he did. It doesnít matter.
Weiner:Once you got started on a problem, did you have to get special dispensation to get equipment, instruments, access to things you needed?
McMillan:No. I presume your supervisor probably arranges this. I had no problem. I dealt directly with the shops and the glassblowers for building equipment and getting things ordered that I needed. I suppose there probably were some official signatures behind the scenes, but I was never aware of any problem. Of course, the scale of apparatus then was nothing like it is now, and the whole cost of this, which I wonít try to estimate, would be a small fraction of a typical experiment today. But still and all, for a thesis problem it was a fairly elaborate problem. I had a pretty complicated piece of equipment, parts of which I made myself, but the complicated parts were made in the shop or by the glass blower. You have to have a vacuum system. You have to have a source of high voltage for the deflecting electrodes, and I invented a special shape of electrical field, generated a field between two electrodes, and you make those in a particular shape so as to get a certain shape of field which had the property of giving a uniform deflecting force on a molecule with an electric moment. I invented that. That was my invention and I wrote a paper about it which I published.
Weiner:Is that the one in 1931?
McMillan:Thatís about right.
Weiner:Thatís ďAn Electric Field Giving Uniform Deflecting Force on a Molecular Beam.Ē A letter.
McMillan:Thatís it. That was my own invention. So we had those plates made, and we had to have a source of voltage which was a Thordarson transformer. We had some Leyden jars for condensers. A lot of the equipment of course came out of the stockroom there. The elaborate part of the apparatus was the velocity selector. If you do a molecular beam experiment, the molecules come out of a little slit and proceed into a vacuum and travel in a straight line, and the experiment is to deflect those and then measure the amount of deflection by some kind of force. And of course the amount depends on the speed—the faster they go, the less theyíre bent. If you take the molecules as they come, they have the Maxwellian distribution of velocity. So I wanted to make a velocity selector which would pick out of this mixture of velocities this one particular band, so I could get a sharper deflection. So I had this rather elaborate velocity selector built. Itís a rotating cylinder with slots in it, and I wonít describe it in detail...
Weiner:This is in the paper?
McMillan:Itís in the paper, yes, the principle being that a molecule of a certain velocity will pass into the slot at one point, and then will carry down the line; the next slot will be in place for it to go through that one. If itís going too fast or too slow, it wonít get through, so it picks out one velocity. That was the elaborate part. For that, the wheel and the bearings were made in the shop. The little motor that ran it in vacuum I made myself. Itís the only time I ever wound the armature for an induction motor. The experiment did work. I did get results. However, not with the velocity selector. That part I never was able to make work, but it wasnít necessary for the thesis. I wasnít able to resolve the individual quantum states. The problem was that the lubricant in the bearings gave off vapors which fogged up the detecting surface. I was detecting these molecules by freezing them out with a liquid air-cooled surface, and the vapors from the lubricant simply fogged that surface, and I was able to detect the central image of the undeflected beam coming through, at the same time that the wheel was turning, but not good enough to do the experiment, to see the deflected states. It was a successful experiment. It was my thesis.
Weiner:Did you have a theoretical interpretation of it which you put in?
Well, theory predicts a certain value. It was not what I callóitís not an experiment that would lead to a new discovery. It was more in the nature of verification of well known theory. It would have been nice if Iíd been able to resolve these quantum states. I got the gross deflection, with the Maxwellian distribution, which you then fit to a theoretical curve, and the fit was good, and I got a value for the electric moment out of it. But it wasnít a great contribution. In order to try to finish the last part of this, namely the velocity selector part, stayed through my last summer in 1932. Instead of getting the degree in the spring as one would normally, I stayed on through the summer, worked the whole summer trying to get this velocity selector to work, with the results Iím telling you about. It was an interesting summer. Princeton is or was then at least a town that more or less closes down in the summer.
The university at least, I pretty much had the place to myself, which was not bad. An interesting phenomenon, if one wants to know about interesting phenomena—Japanese beetles came. You know, we donít have Japanese beetles in California, so Iíd heard about these things but Iíd never seen them before. They came in swarms and they settled in the ivy outside of Palmer Lab where I was working, at my little basement window. I would sit there and listen to the beetles eating the ivy off the walls. You get a large number of them and they make a very audible crunch, crunch, crunch, and they laid bare all the ivy on the wall. That was an interesting phenomenon.
Thunderstorms were another. Itís a great place for summer thunderstorms, and I think possibly some of the best thunderstorms I have seen were during that summer at Princeton. I recall very vividly, an occasion on which—whatís the guyís name—Iíve got a block on the guyís name—not Shenstone—the great astronomer Henry Norris Russell, right. Henry Norris Russell was standing under the arch in front of Palmer Lab. I was there with one or two other people watching a magnificent thunderstorm, really a beautiful storm, crashing and banging and illuminating the sky. And Henry Norris Russell said, ďIf a thunderstorm were as rare as a total eclipse of the sun, people would travel halfway round the world to see one,Ē which I thought was a very good statement. One of the grandest spectacles of nature. Itís so common, people think nothing about it, but to a Californian, where thunderstorms are fairly feeble things, it was a great experience.
Weiner:You know, on that campus in 1842, Joseph Henry was measuring the electrical discharge during a thunderstorm and detecting radiation over distances of 20 miles, which was the predecessor of Hertzís work, actually. And it was because there were so many thunderstorms there.
McMillan:One of these storms ignited a barn out in the countryside, and I went out and watched this fire, a great barn fire. Another thing, in the naturalistic type of observation— the cicada—the 17óyear locust. They were out, making their addition to the noise level. It was a very noisy summer. I caught this cicada and dissected him, and observed the rather marvelous complicated sound-producing mechanism which those things have. Iíd never heard before how they go about it, and I was very impressed with the machinery that animal has. But to get back to the main story, the thesis was finally written up and accepted.
Weiner:Did you have a change of advisor on it along the way?
McMillan:That is right. Sorry, I forgot that. Zahn left and Condon came in and I asked Condon to be my supervisor, thesis supervisor or advisor, whatever you want to call it, which he consented to do.
Weiner:He must have been involved in his own problems. What kind of commitment does that mean?
McMillan:Oh, signing the thesis. He of course is a theorist. I think I was the only experimental student he ever had. He took this position I think with the condition that I wouldnít ask him for advice on how to do the experiment. I promised him I wouldnít, and he came down and looked at this and said, ďTo think that I have a student with a piece of apparatus like that.Ē Typical Condonish kind of thing.
Weiner:I think his recollection of this was the same but with another emphasis, and that is that you put the condition on him that he not interfere.
McMillan:That may be. That may be.
Weiner:That youíd like him as your thesis advisor as long as he left you alone.
McMillan:It may have been that way. I know we had this agreement, however it was stated.
Weiner:Thatís very interesting. The fact is that you continued pretty much independently then?
Weiner:How about Zahn? Was he involved on a day-to-day basis?
McMillan:Not really, no. It was very much individual.
Weiner:want to ask a number of questions about the general atmosphere of Princeton, as compared to what you had in your experience at Cal Tech, in the scientific life, the knowledge, awareness of what was going on around you.
McMillan:Well, it was very different, of course. For one thing, was living at the Graduate College, where the majority of graduate students are non-scientists. The Graduate College accommodates all graduate students. That is, all who live there. Itís a living hall, itís not a college in the ordinary sense, a living hall. So I had much more contact with people in the humanities than I had at Cal Tech. I had some very good friends among people in other fields, suppose one could say it was more of a gentlemanís atmosphere than Cal Tech. Cal Tech was a technicianís atmosphere. Science was all, dress very sloppy, very informal—but Princeton people dressed better. They were more careful of their speech and so on. It was more of a gentlemanly atmosphere, which I suppose one learns something from. At the Graduate College they had the custom of wearing academic gowns to dinner, which they still do as far as I know. That was sort of interesting to me.
Weiner:Dining clubs or what?
Well, the Graduate College is its own dining club. That is, itís patterned after a monastery. Thereís a refectory. You all eat at the refectory at long tables, and everybody has academic gowns on. The academic gowns descended from one person to another. When anybody left they handed them on to some guy coming in. So they were pretty tattered and torn. They werenít very beautiful, but they were clearly academic gowns. There was always grace said, and the meals were rather formal. The only sort of boisterous conduct was cookie rolling. Sometimes they would make the mistake of serving round cookies, and then there would be cookie rolling—down the long tables—attempts to see how far you could make a cookie go before it runs off the edge.
Usually they were careful to serve square cookies, but if they ever made that mistake, there would be that. There was a little bit of high spirits there, but it was a fairly sober, serious group of people. One element then which we donít have now was the speakeasy. Of course that was during Prohibition, and there was a rather well known speakeasy close to the Graduate College. If you know this place, the Graduate College is on the edge of a golf course. You walk across the golf course. Then you come to a street, whose name I canít think of now, [Alexander Street] that runs sort of down into the sticks, and down that street is an old farm house with a windmill in front, and boarded up windows and a door in the rear, which was Andyís. That was a place that some of us used to go to. It was pretty sober too. People were well behaved. I never saw anything like window smashing or any kind of rioting.
We did go down to Andyís and there was a group of graduate students in physics, of whom I was one, that used to go down in the evenings and drink beer. Andy was a nice fellow. We played bridge there. We used to have bridge games, strangely enough. One other thing I might add is that there was very little mingling between the graduate students and the undergraduates. Undergraduates were there, and I got to know a few, like maybe two or three, but there was no real mixing between graduates and undergraduates. I think the undergraduates felt themselves to be a superior class. They were the true Princetonians, and the graduate students were just people who came there to do some dull kind of work. And I imagine there was a more lively spirit there among the undergraduates, but I was not part of it.
Weiner:They had societies and clubs.
McMillan:They do have eating clubs. They have a lot of things like that.
Weiner:How about things that involved the faculty, either intellectual or social? For example, was there any regular colloquium or journal club meeting in which you were involved?
McMillan:There was a journal club, which I used to go to. Actually the first time I presented a paper in public was before this. But it was run by the chemistry department. I guess I still had my attachment to chemistry, because I knew quite a few chemists, and it was a chemistry journal club. There wasnít a real physics journal club, as I remember it. There were seminars. But this was an informal group that met in a very small room, and normally would pick some recent paper out of a journal and present it. That was where I got my baptism in presenting a scientific paper before an audience, which I was—I was fairly bothered by stage fright in the beginning. But you learn how.
Weiner:What was the subject?
McMillan:I canít remember.
Weiner:But it was something out of the chemistry journals?
McMillan:It was a scientific subject. I think it was even on physics. You know, they werenít proud. Theyíd listen to physics. It was something about physics but darned if I remember what it was.
Weiner:Do you recall that year—we talk about the famous year 1932—you were in Princeton most of that year.
Weiner:Deuterium work was announced. The neutron was announced, the Cockcroft-Walton work gave results. Do you recall any of that?
McMillan:Well, I certainly heard about it. It certainly came to us. I donít recall any great excitement about it at Princeton. The main fields of Princeton were not in nuclear physics. I imagine at Berkeley there probably was enormous reaction. But I didnít get to Berkeley until the end of the year, December 2, Ď32, I got there. Those things had all been done. I donít remember anybody jumping up and down about this at Princeton.
Weiner:I just wondered if Joe Boyce was there.
McMillan:Joe Boyce was there. I knew him. Iíll try to remember people.
Weiner:Walker Bleakney was there.
McMillan:Yes, Bleakney was there.
McMillan:Yes, Shenstone was there, Shenstone, Smyth, Adams.
Weiner:Walter Plimpton Adams?
McMillan:Walter Plimpton Adams was there, Einar Hille in mathematics—whom I saw at the last meeting of the Academy. I saw Einar Hille, I spoke to him. He didnít remember me. Name some more.
Weiner:Was Robertson there?
McMillan:Well, of course, Zahn, Robertson—I saw a lot of Robertson. Iíd known him from Cal Tech.
Weiner:Thatís one we didnít mention from Cal Tech.
McMillan:Thatís right. But Iíd known him. I saw a lot of Robertson. Condon, Wigner, von Neumann, Lou Turner, old C.P. and H.D. Smyth, one chemist, one physicist. I donít think thatís complete. Among the other graduate students, Longacre. Anyhow, Longacre was one of our little gang. And a guy named Don Reed who, I understand, just dropped out of sight. I was asking someone about him a while back and he apparently just dropped physics and, I donít mean heís dead but he just dropped the field for some reason. Don Reed was a good guy, though. Eugene Pike—a strange character, Eugene H. Pike. Well, thatís not a complete list. There was James Brown, Horner Kuper, and many others.
Weiner:Was Van de Graaff there then?
McMillan:Van de Graaff was there. I saw a lot of Van de Graaff.
Weiner:Letís talk about him. Did you know about the work he was doing on the generator?
McMillan:Yes. I was there, I knew a lot about what he was doing. I presume that if he had been a faculty member looking for a graduate student to work with him, I would have been with Van de Graaff, but it wasnít that way. I think I spent as much time with Van de Graaff almost as in my own work. Not as much, no, I did do this job all by myself. But I spent a lot of time with Van de Graaff and followed very closely what he was doing. I was fascinated by it.
Weiner:Did you help him at all?
McMillan:No, not physically. I didnít do any actual assistance, but I certainly discussed everything with him.
Weiner:I know very little about how his work really developed there. Did he have anyone helping him at all or was he working alone?
McMillan:He was working pretty much alone. Then the American Institute of Physics had Barton—Henry Barton had this bright guy named Mueller who came up to Princeton, I think a protťgť of Bartonís, and he was supposed to...
McMillan:From Cornell, yes, right.
Weiner:Thatís where Barton came from when he took the AIP job.
I remember Mueller came to Princeton from Cornell, thatís right, and worked with Van de Graaff and did what I considered a very poor job. I think they set back the development of the Van de Graaff machine several years, between them. Van de Graaff and Mueller both were trying to do things that were good things to do, namely to operate the machine with the belt in vacuum or under pressure. They tried both. But by not succeeding in doing it either way, I suppose they delayed that development by some number of years. It finally had to take Ray Herb to go through this whole cycle all over again, try it in vacuum, then in pressure, to finally get the pressurized machine, which is what everything is nowadays. But Van de Graaff had a machine running in vacuum.
The belt was made out of alternate glass and metal sections, the metal sections being the current carriers, and that belt ran over a pair of sprocket wheels and it was always breaking, piling up in the bottom of the tank. And every time the charging electrode touched one of these objects, it would make a microscopic spark which would break down the whole volume, so it would never succeed for various reasons. Mueller built the pressurized machine with the pressure tank, and that never worked either, I think primarily because they were making the—the vacuum tube was a plastic tube, you know, made of some bakelite impregnated paper material that could never really hold voltage in the presence of vacuum because of the organic matter. For one reason or another, these didnít succeed, but the idea of a belt machine succeeded enormously. Van de Graaff—when Compton went, I meant to say earlier and I guess I forgot, that Compton left shortly after Iíd arrived. Like less than a year after Iíd gotten there, Compton left, so it didnít matter whether I had started with him or not, I guess. I was not destined to work with him. Van de Graaff left, followed him up, some time later. Then they built this huge machine at Round Hill, and I went up there to visit him. Iíve seen that machine with its two big spheres and two big insulating supports.
Weiner:Do you recall the model that Van de Graaff built which was demonstrated at the AIP inaugural dinner in New York in 1931?
McMillan:I donít know. Describe it.
Weiner:Well, Itís about, a little more than manósized...
McMillan:O.K., Iíve seen it, yes. Thatís right, that was built there. That was built at Princeton. I was there when that was built, as a matter of fact. I thought you might mean that one.
Weiner:Do you know anything about that newspaper story of the dinner which showed them with this model? It was a way of dramatizing the Physics Society coming into this federation, and apparently he was successful and it was very dramatic. But you probably wouldnít have known much about it at the time.
McMillan:Well, I didnít know anything about that display, but the model I certainly remember very well. Professor Joe Morris was a great supporter of Van de Graaff. He was at Princeton at the time. I think I give Morris a fair amount of credit for persuading Van de Graaff to go ahead with this development, because Van de Graaff got a little discouraged at times. And I think it was Morris who actually got the parts for this, got him to build it for demonstration. He went down to Trenton and got a flagpole ball for the conductor on top and so on.
Weiner:Tuve was interested in it too.
McMillan:That was a little later.
Weiner:Van de Graaff came back from Europe about 1929, he stopped at Tuveís lab.
McMillan:Isnít that early?
Weiner:Oh, he didnít build it then. No, Tuve waited until Van de Graaff had done his prototypes, and only then started building his. He was interested in it. He was excited about the idea.
McMillan:Well, of course Tuve also started out with Tesla coils.
Weiner:Well, thatís what he was doing at the time Van de Graaff came up with this idea, and then he decided he would like to do that but he would wait for Van de Graaff to do it first.
McMillan:Well, Van de Graaff told me the story of how be became interested in high voltage.
Weiner:Iíd like to hear that—canít get it any other way.
McMillan:I might say that Van de Graaff was one of natureís real gentlemen. He was one of the nicest people I have ever known, to talk to, to be associated with—one of these rare natural gentlemen, was always kind to everybody as far as I know. I donít know if you met him?
McMillan:Of course you will not, now. He would tell these long stories about how these things had started. He liked to talk. When he was a boy in Alabama, he worked one summer for a power company, and he said that this power plant, I think a hydroplant, was located at a place which had the name of Bugtussle. He said that the citizens of Bugtussle later decided that that was not a very dignified sounding name and changed it to Warrior, so itís now called Warrior on the maps.
McMillan:Bug—as in a fight between two bugs, you know. Well, this summer working at this power company fascinated him with the idea of power. He just got completely fascinated with electrical power. And when at some later stage he got interested in electrostatics, he came back to his love for power and tried to devise an electrostatic power system. And he had this fairly completely designed—in conceptual designs, and he had many sketches of electrostatic generators, motors and transmission lines. The transmission line was to be evacuated, so that heíd use the vacuum as insulator to run a million volts DC with a coaxial type conductor, transmitter of power. Heíd worked out the efficiencies of these things. And that was how he got started. Then later he had a fellowship in England while he was working on some problem—I did know but Iíve now forgotten—and put aside these ideas of power development. He came back to the United States and started thinking about it again, and someone, I think probably Joe Morris, got him oriented towards applying this to physics.
Weiner:What part of physics?
McMillan:Well, nuclear physics, for atom smashing, to use the colloquial term. Everybody was working towards high voltage at that time. But for Van de Graaff the roots go back to this summer as a kid working in a power station. He became fascinated with power, trying to devise a complete system, with DC, with electrostatic generators and electrostatic motors, and he showed me his calculations. Of course nothing came of that, but the belt type static machine really revolutionized nuclear physics.
Weiner:When you knew of the work he was doing, were you getting interested and excited about the potential of nuclear physics or was it just another field?
McMillan:I was getting interested in that, yes. When toward the end of my time at Princeton, I applied for this National Research Council fellowship, I intended to come to Berkeley. I intended to work with Professor Lawrence. I gave his name as the person I wanted to be my supervisor, but what I planned to do was a molecular beam experiment, so I was still a little bit tied to the molecular beam field. But the purpose of that experiment was to measure a quantity of nuclear physics, namely, the magnetic moment of the proton. And I actually started and worked for around a year on this, and the result was obtained by someone else. It was published. I got scooped, as they say now. Stern and Estermann. At this point, I dropped that and went into the Radiation Laboratory. Ernest had actually been trying for some time to persuade me to come and work with him on the cyclotron, and I said: ďI started this molecular beam experiment, I want to finish. I want to get this result.Ē And when Stern and Estermann came out with the publication, I had no further reason to continue. I dropped it and went into the laboratory. That would be some time in the spring of Ď34.
Weiner:That was the end of your tenure anyway.
McMillan:My tenure ended December 1, Ď34. It was two years. I arrived December 2, Ď32. The fellowship was supposed to start December 1 and I got it renewed for another year, and so for part of the tenure of that fellowship I was in the laboratory working with the cyclotron.
Weiner:Who did you work with when you first came to Berkeley? It wasnít Lawrence.
McMillan:Well, he was my supervisor.
Weiner:From the start?
McMillan:Oh, sure. As I said, when you apply for this fellowship, you say who youíre going to work with, and thatís what I put down. But the fact was, I was continuing my old habit of working alone and I had no associate. I was working completely alone.
Weiner:Did you preserve among your papers your copy of the application?
McMillan:I doubt it. I wouldnít know where to look. I donít think so.
Weiner:That would be a good thing to find.
McMillan:A lot of things would be good things to find. I sometimes kick myself for being a little bit careless with historically interesting matters. I think I usually had the attitude that when somethingís done, itís done, and I go on to the next thing. I havenít been very good at preserving stuff.
Weiner:You probably have more than you realize, I hope.
McMillan:It may be. Of course, I suppose these foundations have files.
Weiner:Oh yes. As a matter of fact, I talked with the people at NRC about this possibility and theyíre very open to it, as long as Iím preserving anonymity of referees. The actual subject of the proposed research is described in a published thing, but I donít think the application—I know it in Paulingís case, because he preserved his, and theyíve interviewed him, they discuss it in the interviews. He was going to map out the whole field of mathematical chemistry.
McMillan:It sounds like him. And he did.
Weiner:He quoted the introduction to Sommerfeldís book about the need for this and that kind of thing. What I was looking for here, this is from Birgeís history, and well, I canít find it exactly, but I thought you were coming to work with someone else, and youíre saying that you came to work from the start with Lawrence.
McMillan:Thatís right. Heís the only person I put down. Of course I conferred with him. He wasnít actually supervising me. I was always my own supervisor.
Weiner:Before we jump into that, I want to go back to Princeton. A couple of questions come up. We were talking about Van de Graaff and about your own work. What about the work of Condon then, which was theoretical. Thereís a man whose work touched on a lot of things, including nuclear physics. Did you have any real contact with him, attend any lectures?
McMillan:Well, I took a course from him and knew him personally very well. We must have discussed physics, but he was a theorist and I was an experimentalist, and I tried to understand theory but I never had any pretensions of doing it. You know, I never had any pretensions of contributing original work in theoretical physics.
Weiner:What about other people, students? Werenít Bardeen and Seitz and Conyers Herring there at the same time?
McMillan:Seitz was there. I donít remember Bardeen at all. Seitz was a graduate student. He was I think something like two years behind me. I did know him. I also knew George Shortley, who wrote a book with Condon. I knew George Kistiakowsky in chemistry. I knew him pretty well.
Weiner:In addition to what you said about Comptonís research interests, would this pretty much characterize the kinds of physics research interests going on during your period there?
McMillan:Well, the single biggest field was the discharge through gases, what we now call plasma physics.
Weiner:So Van de Graaff was...
McMillan:Van de Graaff was working more or less, Iíd say probably entirely by himself, except when this young guy Mueller came down. Mueller is at Los Alamos and I saw him recently.
Weiner:Then some time during your last semester or year there, you prepared your dissertation. You must have had your orals about that time too.
McMillan:Yes. They were considerably earlier. Donít ask me the timing on those things.
Weiner:Itís not important, I was just curious who was on the committee, if you remember.
McMillan:The only one I remember being on was Robertson, H. P. Robertson. I remember him making some sardonic remark. He liked to scare students. But I canít remember...
Weiner:Iím just trying to characterize, these steps you go through.
McMillan:But I took a course on relativity. I remember the quantum mechanics pretty well, especially Wignerís, where I learned a lot. There was a course in general relativity that H. P. Robertson gave, which I barely understood at all. I think large parts of it not at all, which is probably why he made these sardonic remarks. I think he knew I wasnít understanding it. Iím not a real mathematician. I like mathematics, but Iím not a real mathematician. I donít have the facility to handle mathematics the way you really need to, have to, to do those things.
Weiner:I think, characterizing the period, it seems to me, and itís just an impression, that your main focus was on the specific research problem.
Weiner:And that it wasnít a relatively big educational experience otherwise; the other things just fitted in as part of the background.
McMillan:Thatís right. Thatís fair.
Weiner:What were your expectations? Here you are obviously going to get a Ph.D. What did you think youíd be doing with it?
McMillan:I can honestly say that I wasnít worrying about that. Somehow I suppose I had some sort of built in optimism, or maybe itís just unconsciousness, but I donít recall worrying about it. I knew there was a depression on, and when my fellowship finished, which was December 1, Ď34, they gave me a research associateship in the department without pay. Then in Ď35, July 1, was appointed instructor. For seven months I was research associate without pay. During that time I had a good offer to go to Princeton. I think I had more than that, but I remember specifically Princeton.
Weiner:There was one for Michigan too, wasnít there?
McMillan:There may be.
Weiner:According to Birgeís letter.
McMillan:There may be, Birge would have that down better than I do. I had decided I wanted to stay here, and I think Birge had made some indications that he was trying to get me on the faculty. Anyway, I didnít go, and I donít remember worrying about it. Iíd saved a little money from the fellowship. Life was cheap then. I borrowed some from my father, as I remember, a few hundred bucks, and carried through.
Weiner:Talking about money, at Princeton...
McMillan:It seems very different now, now that Ph.D. making has become an industry and physics has become an industry, the new Ph.D.ís seem to be scared stiff about getting a job. Thereís a lot of agony over it. The times were worse then than they are now—I donít remember that much agony about it. As I say, maybe I was unconscious. I was not married. I was living at the Faculty Club. The rent was very low. I remember something like $20 a month or maybe it was even less. I think it was $20 a month I was paying for a room, eating there which was not expensive. I didnít have many needs. I didnít own a car then. Later after I got a job, I bought a car. But I seemed to get along all right. Do what I had to do. Living in the Faculty Club, which was just practically across the street from the laboratory, you know, just about a block away.
Weiner:Let me go back to Princeton a minute. You mentioned you had some fellowships at Princeton.
McMillan:Yes, I did.
Weiner:What were they? Were they competitive?
McMillan:Well, there were not specific competitions. They were based on something or other, like some group of faculty deciding on the basis of performance. They werenít competitive scholarships in the sense that they didnít have a competition where you do a specific thing, I think they were given largely on the basis of your grades and the judgment of your professors. I know my last year I had the—there was what was considered one of the best ones which was I think called the Jacobus Fellowship, does that sound right?
Weiner:That sounds familiar. Iím not sure. I know thereís a Coffin scholarship too.
McMillan:No, Jacobus, I think. This one I had the last year, and thereís a particular room in the Graduate College that goes with that. This room belongs to the Jacobus Fellow, and I lived in that room—right over the arch. If you go in the Graduate College, thereís a big entrance archway and thereís a room right over that, you see those windows—I lived in that room. It was very nice. You could look out both sides, see the outside world, or you could look into the quadrangle and see what was going on.
Weiner:These helped to pay your expenses basically.
Weiner:It didnít involve any responsibility in any way?
Weiner:For this entire period at Princeton you had no responsibility except doing your dissertation?
McMillan:Thatís right. I never got into teaching, anything like that.
Weiner:Toward the end you took the decision to apply for a National Research Fellowship.
Weiner:Why did you make that decision?
McMillan:Why did I do that? Because everybody did that. Thatís what you were supposed to do in those days.
Weiner:You mean, after the Ph.D.?
McMillan:Sure. Thatís what you do. You try for a National Research Fellowship. That was the big thing then. It was very important, I think, in the development of American science, these fellowships. Any number of people—like Pauling was a National Research Fellow when I first knew him. You go down the list of people of that generation, youíll find a large proportion of us were on that Fellowship. Itís what you do. Youíd have had to ask ďwhy didnít I?Ē if I hadnít applied. The only reason I could think up for not applying is if you got an immediate job, you know, if you got your Ph.D. and somebody came and made you a big offer for a job and you took it, but otherwise, this was the natural thing to do.
Weiner:Unless you didnít have expectations of getting it.
McMillan:I mean, anybody who thought he was any good thought I was some good.
Weiner:You indicated that you specified you wanted to work with Lawrence.
Weiner:How had you become aware of Lawrenceís work?
McMillan:That I donít remember. He had visited Princeton. I had met him, and as you mentioned earlier the nuclear field was coming on strong then, and I was very aware of that and I wanted to get into it. And my idea of getting into the nuclear field was to first do this magnetic moment, an important nuclear parameter, and then build on from there, and Lawrence was the man I wanted to work with. He was already a very well known man.
Weiner:You could do that magnetic moment work just about anywhere though, right?
McMillan:Sure, Right. I did it in the basement of LeConte.
Weiner:So it wasnít because working for him provided any special facilities.
McMillan:No. It was because of the person, because of the man.
Weiner:Did anyone have any say on your application? Did you send it in directly? Did you go through some intermediary?
McMillan:I donít remember that. I simply donít remember that. I am sure that my supervisor had something to do at least with countersigning it or writing recommendations or something, but the mechanics I donít remember at all.
Weiner:Had you written to Lawrence beforehand to find out if youíd be welcome?
McMillan:Yes. Either written or spoken to him, I canít remember which.
Weiner:Was this a surface thing or was there any real involved discussion?
McMillan:No. As far as I remember, I just said, ďIím going to apply for a National Research Fellowship and Iíd like to work with you, is that OK?Ē and he said, ďFine.Ē Thatís about how deep it was.
Weiner:You had word that you received it before you concluded your Ph.D. You must have gotten word in the spring of Ď32?
McMillan:I believe so, yes. I donít remember that. Certainly before I finished my thesis work, got the thesis signed, fulfilled all the requirements, and left Princeton, arrived in Berkeley, the end of 1932. But if you look in the records of Princeton University, youíll find that the final acceptance of my thesis was on January 12, 1933. And if you look in the Princeton records, they always put me down as Ph.D., Ď33. I thought once Iíd try to get them to change that but I decided it wasnít worth the bother. I donít think they will. Officially it was awarded in the beginning of Ď33 but I will continue to put down Ď32, because otherwise it botches up everything else. If I say I started work in Berkeley in 1932 and got my Ph.D. in 1933 that doesnít make sense. So youíll find in all biographical material quotes of Ď32, but if you go to Princeton they will tell you I am wrong. As far as Iím concerned itís Ď32. I left there. I never went back. And then, I never published the thesis, which annoyed Princeton quite a lot.
Weiner:Why didnít you?
McMillan:Well, because again some characters did the same thing and published it before I could have gotten mine out, so...
Weiner:Who in this case?
Oh, same characters, I think, Stern and Estermann, yes. They were always a step ahead of me. They had done this with the nonhomogeneous electric field, the analog of the Stern-Gerlach experiment. So my thesis is published as an abstract. I gave it at a meeting of the Physical Society in the spring. It was an abstract, but the thesis as such is not published. Princeton used to go after me. Theyíd say, ďYou have not fulfilled the requirements, youíre supposed to publish your thesis,Ē and I would write back saying, ďItís much too long to publish. It would be more labor to cut it down to publishable form than I think itís worth as a contribution, and to hell with it.Ē I didnít say it quite that way.
But Condon still charged me occasionally, said, ďYouíre the man who never published your thesis.Ē [looking at copy of thesis] I guess itís not in here, the final date of Ď33, itís in some other paper Iíve got—here it is. You see, I canít publish that. Itís too long. Iíd have to rewrite it. Thatís the beam spread out by the electric field in this direction, on this sensitive surface. It was a polished nickel surface with a layer of ammonia on it, cooled at liquid air temperature. These are just intensity marks. The whole thing rotates, and you get one, two, three, four, with different lengths of exposure, and then you set it on here and make a long run with the field on, and then you measure the brightness—make traces with the microdensitometer across here—those are the intensity marks, and since these were known exposures, you know how much, how many molecules had to hit to make that, that, that and that. That calibrates the scale. Then you take the deflected trace, which is that one, measure it, and use the calibration to find the actual intensity in the deflected trace. Here it is without the field on. Hereís with the field on. You see how it spreads out. Itís a little broader with the field on. Thatís the only difference you get.
McMillan:I canít remember—oh yes. He did suggest—OK, so he suggested it.
Weiner:Zahn suggested it, yes.
McMillan:Oh yes, and Ladenburg came in while I was there. He was department chairman.
Weiner:Here is a reference to an abstract by Robertson and McMillan.
McMillan:Well, Iíd forgotten it. Computations done by Robertson. I donít remember having any part in it.
Weiner:It would be good to look it up and see. It is you, Iím sure.
McMillan:Maybe Robertson wrote it and put my name on it.
Weiner:Can you remember what meeting it was for as an abstract?
McMillan:No, I donít, letís look it up. I donít think the library here goes back that far. Would you...?
Weiner:...on microfilm, when I get back to New York...
McMillan:When you get back, tell me what it is. Iíve forgotten.
Weiner:Iíll also look it up in the APS bulletin.
McMillan:Iíd forgotten all about that. Some of this stuff I remember. Havenít looked at this for years. Anyhow the source of the beam is there, and it travels through this slit here, thereís the deflecting field, thereís the collector plate—the velocity lector sits in that space-there it is. I did a lot of this glass tubing work myself. Thereís the deflecting plate, fancy curve. You see the results. Interpretation here. Oh, the velocity selector comes in a separate part, because it didnít get used in the experiment. Where is it, itís gotta be there. There it is, thereís the thing with these slots. See, this wheel spinning, like that, and the molecules traveling like that, and if itís going the right speed—this thing is always getting out of the way as it moves along, if itís going too fast or too slow it hits fore or aft. Thereís that motor armature that I wound.
Weiner:What happened to that?
McMillan:I actually gave the rotor and the deflecting plates to Rabi. Rabi admired it so much I gave him that. I think he still has it. But everything else was cannibalized. People werenít very good at keeping old apparatus. Thatís the theory of this fancy field I was telling you about.
Weiner:This would have been a good job to reduce for publishing.
McMillan:It makes no sense, because thereís nothing, thereís no information in there that one couldnít have gotten elsewhere. No new result came from this. It was sort of confirmation of theory, and with these other guys publishing a similar result, I donít think with quite as fancy equipment as mine but a similar thing, I saw no point. But they still kept going after me, and I expect there are still people at Princeton who feel I really let them down, the only graduate student that never published his thesis. But I think thatís part of what I said to you earlier, that usually my attitude is, whatís finished is finished and go on to the next thing. Iíve never had a tremendous interest in digging up the past or doing unnecessary things that arenít forwardólooking.
Weiner:Well, letís talk about the past again. It seems to me that had a tight schedule. You submitted the thesis and it was accepted November 26.
Weiner:You were arriving in Berkeley December 2?
McMillan:Sure. Iíd finished all the other requirements earlier. Iím sure the fellowship was all through and was simply contingent on finishing the thesis. Thatís often done.
Weiner:Did you go home for a while between institutions?
I arrived in Pasadena November 28, in the Grand Canyon Limited.
My father, Edwin Harbaugh McMillan, was born in Accident, Maryland, on June 17, 1871. His father spelled the name, ďMcMillen,Ē but my father and his paternal twin, William Thomas McMillan, changed the spelling to the present one, on the ground that this was the correct one. After some years spent as a schoolteacher in Hagen (now Lulu), Florida, and later as a pharmacist in McCook, Nebraska, my father took the degree of M.D. at Northwestern University Medical School in Chicago on June 16, 1904, and registered for practice in California on January 16, 1905. He was married in Pasadena on December 25, 1906, to a sister of a classmate at Northwestern, Sam Mattison. He died in Pasadena on September 10, 1962. His brother Will practiced medicine in Los Angeles. My father had one other brother and four sisters, one of whom married Dr. Edwin Harbaugh Glotfelty (after whom my father was named) who practiced medicine in Accident, and one of whom married Dr. Asa Fry Speicher, who practiced in Los Angeles. A son of Dr. Speicher, Ernest Speicher of Los Angeles, and a son of Dr. Glotfelty, Webster Glotfelty of Pittsburgh, PA, were dentists. Also a daughter of Dr. Glotfelty, Helen, married Arthur Rinard, a dentist in Pittsburgh. My mother, Marie Mattison McMillan, was born in Buffalo, New York (Anna Marie Mattison) on October 24, 1869, was raised in Baltimore, Maryland, and came to Pasadena around 1905, where she married my father in 1906. She died in Pasadena on May 17, 1960. She had two sisters and eight brothers. Three of the brothers, Fitch Champlain Edmunds Mattison, Samuel Jones Mattison, and Eugene Graham Mattison, practiced medicine in Pasadena.
Coulter became a patent lawyer, and is now retired. Harness is now (CIT Alumni Directory 1972) Dean of the School of Engineering, San Fernando Valley State College, California. Lash was a Research Associate at the Pan American Petroleum Corp. at Tulsa, Oklahoma; Lombard was Director of Research at the McDonnell Douglas Corp. at St. Louis, Missouri; Pierce worked for several industries as well as the Government; these men are all retired. Schweinfest and Solomon died young, Schweinfest of leukemia and Solomon in the crash of a small plane, while he was teaching his younger brother to fly.