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Interview of Allen Shenstone by David DeVorkin on 1979 March 20, Niels Bohr Library & Archives, American Institute of Physics, College Park, MD USA, www.aip.org/history-programs/niels-bohr-library/oral-histories/5909
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Discusses his family background and education; World War I experiences; J. J. Thomson; return to Princeton as a graduate student in physics; research at Cambridge/Rutherford; Toronto, spectroscopy, and McClennan; collaboration with Russell; team of Russell, Turner, & Shenstone; laboratory astrophysics; spectra of highly ionized elements; publications; Charlotte Moore Sitterly; World War II years in Ottawa; Manhattan Project; radar research; Radiation Laboratory at MIT; retirement from Princeton; his debt to Russell.
Could you give me a little introduction into your own life, your family, background?
Yes. That you will find, I think, partly in the write-up that I wrote for the Institute of Physics. I was educated in Toronto. My family lived there. My family was a businessman. I went to the public schools and to the Collegiate Institute, which is the Canadian name for a high school, and I took the examination there for entrance to Toronto University. There are two sets of those junior matriculation and honors matriculation.
I did the honors matriculation as well. At the time, when I was in my last year in Collegiate, I was debating where to go to college. My brothers had been to Toronto University, but my sister had attended Bryn Mawr. One brother had been to Dartmouth and what was then known as Boston Tech, MIT. And I'd a cousin who had come to Princeton in the class of 1907. He had come here because of a contact in the summer in Muskoka Lakes with Woodrow Wilson. And that was the connection with Princeton really. I also had a brother-in-law who also came to Princeton in the class of 1902.
I wrote to several colleges and finally decided to try to attend Princeton, and my family thought it was evidently best to make it as hard as possible for me, because I was put on a train in Toronto with trunks and bags. I'd never been away from home in my life before, myself, and had to change trains a couple of times to get to Princeton. I arrived here, as apparently the only Canadian undergraduate in the University.
I remember very distinctly reaching the Princeton station, which was then at the bottom of Blair Hall Steps, and walking up those steps, as a very homesick boy, then interviewing the registrar, and finding that they would admit me all right on the Canadian examinations. But they gave me two conditions. One, they didn't think I had read enough Latin, and required me to get a third group in Latin freshman year.
A third group?
Yes, well in those days in Princeton, the groups were first, second, third, fourth, fifth was failure.
So these were graded groups?
Yes, these were graded groups, and the second condition was that I take solid geometry, which I had not studied at all. I may say that in the first ter, of freshman year, I had no friends and had lots of time to study, I got five first groups. This canceled the Latin, and I worked up the other one by myself. I was good in mathematics. That's how I came to Princeton.
Who were some of your mathematics professors?
Well, at the time in Princeton, there was an honors mathematics and physics course, which you entered in junior year. In my sophomore year, however, I had Dean Fine in higher algebra, I presume it was called, I've forgotten the title now. At the end of the course, there was an examination which carried with it a scholarship for the next year, and Dean Fine gave us a very long paper to do, and sat us down in a room, and told us we could work on it as long as we liked.
There were two of us - we went on to mid-afternoon working on it. I've forgotten whether we shared that prize, or whether I got it myself. I know I at least got half of it. That was my first well known professor of mathematics. I had had, in classes in the physics department, well known physicists, E.P. Adams, and people like him. When I entered the honors mathematics and physics course, we were exposed to very top rank people. In that course I had mechanics with Veblan and electricity and magnetism using Jean's book, with E.P. Adams.
Were there any recollections of Jeans' tenure here, when he was here?
Well, I can give you some, yes, but let me finish what I was saying. I had, in the senior courses in the honors mathematics and physics, Wedderburn in mathematical analysis. He was a very famous internationally known mathematician. After I graduated, I did four and a half years as a soldier in the British Army, and when I came back, I found the examinations I had taken in that course. I had forgotten so much that I did not even understand what the questions meant, let alone be able to do them, after four and a half years.
I'd like to know what your recollections of Fine were, what kind of a person, what kind of a teacher he was, and then some stories about Jeans. I now that you didn't overlap Jeans.
No. Well, Fine — he was a very good teacher in mathematics. That was the only thing I knew about him personally. I knew his daughter very well, but that didn't mean I knew very much about him. He was, of course, a very high ranking member of the faculty. At one time, I think, he was considered a sort of dean of all the scientific parts of the faculty.
You referred to him as Dean Fine.
Well, he was Dean of the Faculty, for a time. We also had Dean McGee in the Department; he was also a Dean of Faculty for a good many years.
Was there anything in Fine's style of teaching that was noteworthy?
He was rather gruff. Yes, rather gruff. He didn't have much finesse about his teaching, but it was down to earth good teaching all right. We learned a great deal from him.
Were you more interested in mathematics after you finished his course or not?
Yes. I was always very much interested in mathematics. In fact, after the war when I was coming back to Princeton, I asked another dean whom I had known very well, not a scientist, Dean Gauss, whom I had known as a friend very well, to see if he could get me a fellowship in either mathematics or physics. He got me one in physics, and I think I can thank God for that, because I would never have been able to catch up in mathematics. I never did manage to catch up in physics really, because I'd forgotten so much, and I didn't have time to re-do it all.
Because of the four and a half years?
Yes. I caught up enough to understand what people were doing. That's about what it amounts to.
What are the stories of Jeans?
Well, the stories of Jeans are usually on the subject of how rude he was.
Oh yes. He was a very rude fellow. One of the stories is that another member of the faculty, who knew him slightly, not in physics or mathematics, called on him in his rooms one night. After a rather desultory conversation, Jeans went over to his desk and got a box of cigars and brought them back and said to the guest, "Do you smoke?" The professor said, "Yes, I'd love to smoke a cigar." And the story goes that Jeans then said to him, "Yes, take one, you can smoke it on the way home." Another one was meeting some colleagues on the campus on a beautiful day, and the other man saying to him, "It's a most beautiful day. Why don't we take a walk?" And Jeans answered, "Yes. How short can we make it?" I have one other, too, which I know is a true story because it happened at a dinner at which my wife was sitting on one side of him, and the Dean of the Graduate School's wife, Mrs. Trowbridge, sitting on the other side, and this lady, who's a very very proper sort of woman, said to him, "I've just recently read your book about the universe. I think I understood it." And Jeans turned to her and said, "Yes, a lot of people think they understood it."
This was in the 1920's or thirties?
Yes, that would have been in the late twenties or early thirties. I'm sorry, I've forgotten what the occasion was.
What about the reason for Jean's leaving? Do you know anything about how he was received at Princeton? Was he happy here?
I don't know really very much. He was never considered by the mathematicians as being really a mathematician, though that's what he had been in Cambridge. The mathematicians of Princeton have always been very [pure you know, and they didn't think that anybody who could deal with the problems of electricity, or the problem of gases, as being a mathematician. He was a physicist, but I think he was in the mathematics department. The person who came about that same time and was a real physicist was O.W. Richardson. You'll find out about him in this little book — he appears in here.
The Sixty Years of Palnger Laboratory?
You do mention in there that you talk about him.
Yes. Oh, there is mention of Rutherford here, too. Oh yes, and I quote this wonderful letter that Richardson wrote to a technician who had served 50 years in the department. It's all down there so you can get it; it really is a wonderful letter.
One of the most important questions I have, which I think has been answered just by dates, is whether Jeans and Russell had any contact? I have the impression that Jeans left as Russell came? Or were they here together?
Well, Russell was here from about 1900, wasn't he, or a little after? When did he come on the faculty? He was in Cambridge for a few years.
Several years. He was on the faculty here starting around 1905-07.
Yes. Well, he just overlapped Jeans then, I guess. I don't know Jeans's dates.
I had the impression that Jeans was here earlier.
Yes, but I think he stayed until 1909 or something like that. They probably did overlap. I have no recollection of any contact between them, no.
Did you have any contact with Russell, or did you come to know of his reputation while you were an undergraduate?
I think as an undergraduate I knew of him, but I certainly didn't know him, and I didn't take any courses in astronomy. But one person that I did know as an undergraduate, J.Q. Stewart, class of '15, was of course very intimate with him later on because he went into the astronomy department. But I think the first contact I had with him was in fact these Sunday night talks at the graduate college, when I came back from the war.
We'll get to that in a moment. Do you recall Stewart talking about Russell at all?
No, I don't, really. I have no definite recollections of it at all.
So there was just the general knowledge that he was on campus.
Oh yes. Yes. There was spread around even at that time, perhaps, the fact that his undergraduate degree had been given with a special citation. You know, it was something beyond summa cum laude, they gave him. I know, one recollection of Dean McGee's about him, Dean McGee was a teacher here when Russell was an undergraduate. He said that the first time Russell sat in one of his classes, he found that Russell knew everything that he was going to teach. So, he took him aside after the class, and told him that he would prefer it if he did not come back. Dean McGee felt that it would be upsetting to him and to the other students, because he knew too much.
This was in what, mathematics?
No, this would have been physics.
In physics. Do you have any idea what class that was?
I don't know, but it was probably in the sophomore physics course that he gave. He was still giving it when I was an undergraduate, so it was probably that. The other thing that he did teach was thermodynamics, but I don't think it would have been that. I think it would have been straight physics.
I'm interested in finding out more about Russell's teachers. Another one of his teachers was Fine.
Do you know how close he was to Fine?
I haven't the slightest idea. They probably knew each other fairly well, because they both were residents of Princeton, you see, not only faculty members. Fine was living here and Russell I guess was brought up in Princeton, and he married a Princeton girl, I think. Princeton was a small enough place at that time so that residents who had any connection with the university were apt to know each other pretty well.
Yes. I can understand that.
It was a small faculty as well.
So he was a generally known name on campus. Was there anything particularly known about him other than his undergraduate career, when you were an undergraduate?
No, I don't remember anything, no. No, I don't. It's awfully far back, you know.
Oh yes. Yes.
I haven't tried to write the part in my autobiography up to 1914 yet, so I haven't been trying to drag things out of my memory or out of any papers I have, you see.
I'll try to act as a stimulus. Well, you went into the Army for 4 1/2 years then.
I went to Cambridge in September, 1914, to be a graduate student at Cambridge.
Oh, I see. In mathematics?
No, in physics, under J. J. Thomson, and I was accepted as a graduate student. I'll tell you something that you probably are not aware of, because I've never found an American who was aware of it — that Oxford and Cambridge, before the First World War, gave no doctors' degrees on graduate work. The only degree you could get in Cambridge for graduate work was a BA. And that's what I was a candidate for. There were no graduate degrees that were given on examination or honors thesis.
I didn't realize that.
They introduced the Ph.D. at both places after the war, I suppose really to compete with the German Universities.
And of course the American Universities had taken it up some time before, too.
Yes. So I went to Cambridge as a graduate student in Emanuel College. I had to be a member of a College. And I was handed over by J.J. to C.T.R. Wilson, to find out how much I knew and try me out on come small experimental job to see it I had any talent at experimental work. But I was only there for two terms, actually not the whole of two terms, because in February, I started looking for a war job, and was commissioned in the Royal Engineers in March, 1915. I think the date was the 28th. That I can check up on. So that's all I saw of Cambridge at that time. I went back after the war. When I was a graduate student here, I went to Cambridge and did a thesis there with Rutherford. They let me continue on the BA because I'd started on it. I probably was the last person to get a BA on research from Cambridge.
That explains why you have your degree from Cambridge in 1921 and your Ph.D. from Princeton in '22.
I thought that was very interesting.
I went to Cambridge for two terms. I had to make up tow more terms. Six terms were required for the degree. But all I had to do was to do the thesis work and have it accepted by Rutherford, as a thesis, and published, and that gave me the BA degree, and of course as you probably do know, the MA at Oxford and Cambridge does not come on examination or on anything of the sort. It comes on keeping your interest in the University and the College for a certain number of years and paying your dues and applying for it and paying a fee for it.
I've heard that.
Yes. That's the was you get it. But actually, the MA at Oxford and Cambridge — I know it's true at Cambridge and I think it's true at Oxford too — has certain powers: for anything of extreme importance in the changes at the University, a meeting may be called of all MA's, to vote on it. And also at the time when I took the degree, and this is true up until after the Second World War, it gave you the right to vote for the University's member of Parliament.
I see, so you were a basic voting member of the campus and the community. That's interesting.
Yes. After the Second World War, the first Labor government did away with it. They didn't think it was democratic. It actually gave an MA of Oxford and Cambridge and two other Universities, I think three other perhaps, double voting in the U.K. You voted for two different members.
Yes, right, that's interesting.
But it was a very good system because it at least provided some educated people of high standing in the Commons.
What did you do specifically during the war? First World War?
Yes. Oh, I was an officer with a fighting division. I was a field officer in a field company of Engineers, right up in the front lines with the fighting divisions for almost the whole time. Well, from 1915 to the end of 1917, I was in that sort of job. In 1917, in 1918 rather, I was a Corps Engineer attached to an Army Corps, and was employed on all sorts of rear duties — unfortunately got mixed up in the big attack the Germans put on the 21st of March in 1918.
Did you suffer at all from that?
Well, we retreated very rapidly.
Right, but your personal well being?
No, I was never wounded in all of this, There were many cases where I could easily have been. We were in a lot of action — when I was with the 7th Division, through 1915, '16, '17, we were in nearly every major battle.
OK, we're recording. Did you have any contact with Princeton during the war, letter, or other documents?
No, not anything to speak of. I remember once going on leave to Paris for a few days and meeting a few Princeton friends there. And after the war, going to recover from the flu to a hospital on the Riviera where I ran into a classmate of mine who was an aide-de-camp to General Pershing.
What were your feelings as the war was drawing to a close? Did you want to go back to Princeton or Cambridge?
I wanted to get back to this side first, I think, because I wanted to see it I could catch up with what I'd lost. I had tried to catch up a little, because when I was with the Army of Occupation in Germany, after the Armistice, I wrote to J.J. Thomson, who was still the professor in Cambridge, and asked him to send me some books, to see if I could catch up with what was going on in physics. Actually I happen to have the letter here for another purpose and these are the books that he sent me.
Is this your handwriting?
Yes, that's my handwriting.
"Electron, Theory of Matter, Emission of " — that's by O.W. Richardson?
"The Emission of Electricity by Hot Bodies, "
By O.W. Richardson.
"Rays of Positive Electricity, " J.J. Thomson, and "The Electron" by Millikan.
Yes. Those are the four books that he sent me to try to catch up a bit.
That's marvelous. These books are between 1913 and 1918. Published.
Yes. And I have them all still.
These were Thomson's books that he sent to you?
He sent them to me, yes.
Marvelous. Did he discuss in any kind of cover letter what he hoped your future would be like?
No. He wrote me a letter and I haven't got that. At the time, I knew J.J. only slightly. I knew his son, G.P. Thomson, afterwards, very much better, of course. But I knew J.J. after the war too. When I was there in the twenties, he was the master of Trinity College, and I went to Trinity College and I think I had tea with him or something like that.
But you did decide then to come back to Princeton, and you felt that remedial work would be better done at Princeton?
Yes. I had to first find out whether I was going to be able to catch up at all, and I found that if I stuck to fairly straightforward things, I would be able to get along all right, but when it came to trying, as I did, to read Herman Weyl's "[unintelligible]" I came to the conclusion that that was not for me. (German title?)
What were your feeling when you got back to Princeton? When did you get back to Princeton?
In the fall of 1919.
OK, and you came back as a graduate student?
I came back as a graduate student and roomed in the graduate college. I had a small fellowship.
This was in physics?
In physics. My second year here, I had a Proctor Fellowship, which was a very good fellowship. I can tell you a story about that that may amuse you anyway. The Proctor Fellowship had the condition on it that you had to live and eat at the graduate college, but at this point I was planning to go back to Cambridge, for part of the year at least, and try to get finished there for a degree. I had also applied for a fellowship at Toronto University.
The fellowship at Toronto came through and so I went to Dean West, who was the builder of the graduate school, you know, and the College, and I put it up to him. Either I would take the Toronto fellowship, or I would take the Princeton one if he would allow me to use it to go to Cambridge. And, he being a practical man, said "Go to Cambridge." It was a real hold-up. So I went to Cambridge in January, 1921, and spent two terms there, coming back in September '21, to Princeton to go on with my graduate work here.
Before you'd gone back to Cambridge, had you started going to these Sunday sessions?
Oh, I didn't go to them absolutely regularly. I did go to a few of them while I was, yes, while I was still living at the graduate college.
How did you come in contact with this? Were the Sunday sessions will advertised?
Oh, this was known to everybody in the graduate college.
So what was it basically?
Well, you know, he was a very religious man.
Russell. And this was an attempt by him to bring together science and religion. It was specifically on that sort of grounds that he gave these talks.
What are your recollections of them? How did they go?
Well, they were very well done. Very well done and I learned quite a lot of science from them. To me, it wasn't ever very convincing; he was trying to justify the connection between science and religion.
What arguments did he use? Do you recall any?
Oh, I can't recall such details as that.
Did anyone take notes during these things?
Maybe. I don't know. Are there any other people in Princeton you're going to talk to, that might have known him in those days? Harry D. Smyth might have. You know, H.D. Smyth, the author of the book of atomic energy. He's still around. He's in the Class of '18, so he's four years younger than I am, but he was as a graduate student when I was, because he didn't go to war, you see. He was too late for it.
Is there anyone else?
I don't think so. I don't recollect anybody else now who was there.
Do you recall the general structure? When were they held, about what time of day?
They were held in the evening, on Sunday evenings, in one of the student rooms. I've forgotten now. It wasn't held in a large hall where a large group could be. It was a matter of maybe a dozen or so students at a time, at one of these talks.
Was this a strict lecture, or was it round table discussion?
It was a talk. It wasn't a lecture, it was a talk, followed by a round table discussion. Yes. That sort of thing.
Do you have any lasting or any general impressions of Russell from these?
Oh, one got the impression of his great sincerity, and his extraordinarily wide knowledge of everything. And you couldn't help being impressed by his character, you know, because he was an impressive individual.
But you have no specific recollections of the topics he discussed or anything like that?
No, I don't.
Well, then you went back to Cambridge. You received your BA.
What was your research then?
At that time, Rutherford was looking way ahead, and he was thinking in terms of things that had not ever been discovered. He was thinking in terms, for instance, of the neutron, and he had a student working on an experiment to try to find the neutron, unsuccessfully, as you must know, because it wasn't found until Chadwick had spotted it ten years later. He put me onto another thing which he thought ought to occur, and that was induced radioactivity. That is, bombardment of a substance by alpha rays. This was the only sort of bombardment that one considered in those days.
And afterwards, detection of any induced radioactivity in the substance you were bombarding by observing the emission of protons, that is, H particles, as he called them. Now, this meant that if such induced radioactivity really had occurred, having a lifetime of hours or days, it would have been discovered already in the experiments that had been done. The possibility was that it had a very short lifetime, a matter of fractions of a second, and it wouldn't have been discovered, because the background of the alpha ray activity would have been too great.
So he gave me this to do, with a description of how he thought I could go about it. This involved using a wheel, a metal wheel, doing about 15,000 revolutions per minute, and bombarding it in one spot with a very strong source of alpha particles, and then as close as possible to that, having scintillation screens where you could observe the scintillations caused by any emitted H particles. In this way, lifetimes as short as a thousandth of a second could be observed. And the experiment I did, used a wheel which had originally been part of a gyroscope on a monorail car — it was a brass dick about a quarter of an inch thick. After that it was used by Arthur Compton for testing to see whether high acceleration, in this case centrifugal acceleration, would have any influence on the rate of disintegration of a radioactive substance.
Both these things, of course, yielded zero results. And the radioactivity I was looking for wasn't discovered at all until about ten years later. Rutherford was that far ahead of everybody in his thinking. He had other people working on other problems that were of a very far advanced character. And when I came back to Princeton, I tried to start working on nuclear work here, but it was impossible to get a source of radioactivity. I tried, and at one time was promised a large source of radiothorium from the people who made gas mantles — you know, the old gas lights that had gas mantles on them, that had in them a lot of rare earths and that sort of thing? They were the people who used thorium and had all the chemical abilities to separate it out.
What company was this? Do you recall?
Well, it's the name of the gas mantle, and I can't remember it now.
Was it local?
It was an American firm. Yes. I had worked in Cambridge, England before I did my thesis, with an American named Schlundt. I'd done a sort of service job for Rutherford counting masses of alpha particles, and one of the sources which Schlundt and I used was radiothorium, which Schlundt had brought over with him from the United States. There's a paper of mine on the subject, if you wan to look up papers.
Yes, I'd be interested in at least putting it on the record. Is this an historical treatment?
It's a paper. It's just a paper I published.
That is your bibliography?
Well, it's partial, yes — let's see, this is a fairly complete one, up until '61. But there could be some citations beyond that. I don't think I have another copy. I can give you a reference to that paper. Yes, here it is. It's in Phil Mag 43, page 938 (1922), and the title is "An Attempt to Detect Induced Radioactivity Resulting from Alpha Ray Bombardment." The other on that I did at that same time with Schlundt — he was a chemist from some Southern University, I've forgotten which — was in Phil Mag 43, page 1038 (1922).
OK. When you got back to Princeton, then, you found that you could not continue this work?
There was no use. They finally said they had other uses for the stuff and they couldn't supply it. And you know, it would have been important if I'd been able to do it, because at that time there was a general opinion in this country that Rutherford and his boys had done or would have done nearly everything that could be done in nuclear work, and there wasn't any use going into the field.
Who had this opinion? Physicists?
Oh yes. Yes. You'll find nobody in this country working in the field. Nobody was considering working in the field.
Was part of the problem the fact that sources were not available?
Well, that may be, but I'm sure that if anybody of important had been really wanting to do nuclear work, they'd have found a source somehow, because in fact there were radium sources in the hospitals at that time.
This is a bit surprising. I guess everybody felt that Rutherford had it all tied up?
Yes, they felt that Rutherford and his boys would do it all. All that could be done.
Well, you got back to Princeton, and you were to continue research for the Ph.D. degree.
I'd like to know who your advisor was and what —
E.P. Adams. E.P. Adams and it was a research on the photoelectric effect. It was almost certainly a spurious effect, that I found. So I'm not proud of it. But at that time, you know, physics was in a state where there were innumerable experimental problems that you could work on, for which there was no theory whatsoever.
Other than the basic phenomena.
I see. What was the state of physics then? Were there a lot of interesting little problems that people didn't understand?
Yes, there were a lot of things of that sort. Of course, there was one field that was quite popular here, which had been started by Karl Compton — I guess, in part because of his training under O.W. Richardson, on what were known then as critical potentials. They were in fact experiments to try to connect electrical effects with spectroscopy. And I did some work in that field, before I went to Toronto to teach, after taking my degree here, but I only worked at it for long enough to find out that it was a silly way to do spectroscopy.
Was that your first contact with laboratory spectroscopy?
My first contact with laboratory spectroscopy was when I went to teach at Toronto. I had never in my life had a lecture on spectroscopy, except perhaps for the Bohr atom. I had never observed any spectra, and I had never developer a photographic plate, and inside of the few years I was there, I became a spectroscopist, and not a bad one at that.
How did you decide on this field?
I fell in love with it. I was working on the critical potentials with copper vapor and doing low voltage arcs in the copper vapor. I found that this was fun to do but didn't tell you much. I took a picture with a small quartz spectrograph of the copper spectrum I got from a low voltage arc, and found that it had a lot of lines in it, but that you couldn't tell what they were due to, whether they were due to the arc, or the spark, or what no. And so I had to go on to other things, to differentiate this. I may say in passing, and this is rude of me but it's true, that McClennan was the head of the department there, and he ran it as a dictator. There were two main areas, main parts of physics that were done there. One of them was cryogenics, and the other was spectroscopy.
In cryogenics, it was the first place outside of Holland where helium was liquefied. But McClennan was very jealous of anybody else doing spectrscopy, except under him. And when I wanted to do it myself, he refused to let me use the instruments. He said they were all being used by his students. So, I had to do spectroscopy on the sly, and I used to go in the evening, take what instruments I liked from upstairs, and take them down to the basement, to use them on my apparatus. Well, the second experiment I did, there was one that really sold me on spectrscopy.
It was an experiment to try to differentiate the lines from a low voltage are which were due to the lowest level, or due to some higher metastable levels, and I devised the experiment myself and carried it out and it worked like a charm. I had a quartz tube built about 10 centimeters long and one centimeter in diameter, with a molybdenum liner in it, a heating coil on the outside, and copper inside, to be vaporized. There was a grid in one end of the tube, and a filament for a low voltage are at that end.
This was all in a vacuum with a little hydrogen to prevent the vapor distilling away too fast. I borrowed two identical spectrographs and pointed them at the two ends, and there, you could see which lines were due to the lowest level and which weren't, because the ones of the lowest level were almost absent, after passing through the vapor, strong at one end and weak at the other, you see. The other lines had a natural sort of intensity at the end of the tube where the are was, and at the other end, were slightly decreased in intensity.
Your recollections of this are marvelous.
I still have those plates.
I hope you keep them. I hope that they will be preserved. What decided you upon coming back to Princeton? Why did you come back to Princeton?
I'd like to ask you now about your return to Princeton after Toronto. Why did you leave Toronto?
Well, I was offered an assistant professorship here, along with three other young men at the same time, all younger that I. It wasn't a very high salary. It was all right for those days, $3,000. But — and I could have had a promotion, I'm sure, if I'd wanted to, at Toronto — but I couldn't stand working under McClennan any more. That's basically one thing. And then, I had married an English woman.
That was 1923.
Yes. She has — We both had found Toronto at that time was a rather provincial city. It hadn't grown up yet. It is now one of the great cities on the continent. And she was a London girl, and we both thought coming back here would be the best thing.
Closer to New York?
Well, yes, and into a small town, rather than a large town, thinking it was a city.
I see. Well, then, when you cam back, you became an assistant professor?
Yes. Along with Harry Smyth and a man named Lewis Turner and a man named Charles Zahn. Zahn proved unacceptable finally and was never promoted. He was a very clear experimenter, but he just could not teach. He couldn't teach or keep any sort of order in a class. So he left, but the other three of us were kept on, and in '35, when Adams stopped being the chairman, Harry Smythe took it on, and was for 14 years the chairman of department.
And then you took over from him.
I took over from him. I was chairman for 11 years. Yes.
Well, talking then about the years past 1925, and getting back to Russell, when did you start having contact with him again, and what kind of contact?
Oh, as soon as I got back here, he and I got together, because he was very interested in all spectroscopic things. At that time spectroscopy was in its zenith, you know. It was really becoming, or was, the most important field of research. In Germany, it had moved into such a position. A lot of the scientists were going into it, the theoretical people especially were concerned about it, because it obviously was something you couldn't explain by means of any classical theory. You see, if you look at it carefully, you find that spectroscopy is the mother and father of the quantum theory.
Without it, there could be no quantum mechanics. It started with black body radiation. It went on with photoelectricity, and then it went on to line spectroscopy o the elements. And from those things, was produced the quantum mechanic by Heisenberg and by all the rest of them. And one other discovery that was necessary for the quantum mechanics was the discovery that the electron had a magnetic moment. That was done by spectroscopy.
Russell had already begun this kind of work, especially with the Russell-Saunders work.
Well, this is the most important paper of that time, you see, because it was the paper which took spectroscopy out of the field of thinking that the spectra were due to a single electron and that there were only such things as singlets, doublets and triplets, to the idea that electrons could cooperate in producing terms. Have you seen that paper?
Yes, I have.
I have a copy of it.
Now, I'd be interested to have your recollections, if you have any, on how that collaboration between Saunders and Russell developed.
You know, I don't know. It's very odd, because Saunders was at Harvard and Russell was here. Saunders was also a Toronto man, by the way.
The one recollection I have from Dr. Shenkland at Case is of a lecture that Russell gave in the early 1940's some time, for a scientific meeting here, might have been a sort of semi- popular lecture, recalling how this was done. Russell mentioned that he had taken a laboratory course over for Dugan, who was ill, and this was a laboratory course in practical astronomy. It was cloudy for days and days and days, and in frustration Russell borrowed a laboratory spectrograph from the physics department and started looking for spectra. This is the first time he'd ever looked at spectra, and he saw things he couldn't believe or understand. Does this ring a bell at all, this story?
No, it doesn't ring a bell, except that it is a possible way in which he got into practical spectroscopy, because as a straight astronomer, he would have of course had great knowledge of the sun's spectrum, and what the origin of the lines was, but he wouldn't have ever had to do anything about it, except to accept what people said. But I don't know. This is possible but I have no way of corroborating it or denying it. He doesn't say anything in the paper with Saunders at all?
No, not what I would consider to be a real indication of who contacted whom. The idea was the Saunders was on leave of absence from Boston. He was here.
Oh, he was? I'd forgotten that myself.
Well, I'm not sure whether he — that's the story.
Yes. Oh, I see, yes.
Is this true, that he was visiting here?
I don't know.
That's how they came in contact?
I don't know why he would be visiting here. There wasn't anybody in his field here.
An interesting problem right there. Well, then you came back.
There wasn't anybody until I came back here who did any spectroscopy, at all. Well, that is not quite true. There had been a professor on the faculty who died, oh, I guess during the First World War, who had collected a lot of apparatus for spectroscopy, and literature, but had never done any work with it.
Do you recall his name?
Well, I ought to, .... He built a little concave grating spectrograph.
Yes, which I recently lent to Johns Hopkins, when they had a need.
Rowland centenary, yes.
That's interesting. OK, well, I hope that we can get that name.
We have any number of gratings in the place that were collected at one time or another, including two gratings ruled by a man named Rutherford. In fact, we have three by a man named Rutherford.
Oh yes. This is Lewis Morris Rutherford.
He's certainly a very important name.
And somewhere, I don't have it now, but somewhere in this building, I found a spectrum of the sun, taken by Rutherford with his grating, that was about 15 feet long. And I gave it to the astronomy Department. They're not interested in spectra at all, and they may have destroyed it, but that's where it ought to be.
When did you give it to them?
Oh, years ago. Years ago.
It could have been one that Young had while he was here. Rutherford could have given it directly to Young.
Could be, but how was it in physics? It was in the physics building.
For a number of years, the astronomy people lost their own building or control of it. Mathematics had control, and the impression was that they had to wander around for awhile. This was after Young left, though. This was between Young's leaving and Lovest's leaving, about 1907, and 1920, when Russell made a move to consolidate astronomy again. I don't know how much they were dispersed or what happened meanwhile, but mathematics had control of the astronomy department, the observatory and the whole thing.
I see. Well, however it came about, I gave it to the astronomers.
Do you recall whom you gave it to?
Spitzer, I guess. You will be talking to him, or have you?
Oh yes. Yes.
And Schwarzschild. Schwarzschild is charming.
Oh yes. What was your first contact that you recall with Russell, after you got back, after 1925? Did he approach you for spectroscopic information?
You know, I don't know. I worked with him.
Your first paper was in 1928, with Russell? On a quick method of reducing prismatic spectra?
I guess that's right. That would be it. Yes. But you see, that implies I'd been working with him before that which is wrong. I remember this, that when I came back to Princeton, there hadn't been any good spectroscopic apparatus for me to use, and the department provided for me a large Hilger El spectrograph on wheels, a quartz one, and that's the only spectrograph I had for years. But on it I could take very good pictures in the ultraviolet. I remember taking pictures for Russell of the nickel spectrum, which he had been working on. I gave him the plate which he was going to measure himself, and then I told him the old method of calculating the wavelengths — it's very tiresome — but he realized that if, instead of using wavelengths, you used the wave numbers of the standard lines, —
— the reciprocals —
Yes, the reciprocals, you got a curve which was nearly straight. And therefore you could do what astronomers also did, always do, — a nice linear interpolation and a correction to it. The quadratic connection was very easy to do with a slide rule, and the linear thing was easy to do on a calculating machine, you know, like that one over there. That's a more modern one. And that's what led to him writing the paper, because he had to do it himself. But he was the one who proposed the idea and used it, and then we published it together. Did we or did he publish it alone?
It's with your name.
Yes, the two of us published it together, yes.
What was your input? Did you or he write the text? How did you work together?
I think I wrote it up.
Do you have any recollections of how it was to work with him?
Oh well, he was a very pleasant person to work with. He'd never trouble you, you know. He was always rather loquacious. Do you want me to tell you a story about his loquaciousness?
Oh, please tell me anything.
Well, this occurred at the British Association meeting in Toronto, and I was there.
And this was?
1924, I think. I was standing listening to a conversation in which the talkers were Raman, Professor A. Fowler from the Imperial College, one of the great spectroscopists of the day, —
Right, I'm familiar with him.
— Russell, and myself. I was listening. When they'd finished what they were talking about, Fowler said, "You know, I though Raman talked with the speed of light, but Russell talks even faster."
That's marvelous. Was that your only contact with Fowler?
Yes, at that time. Well, I'd been using his book, of course. It was the bible.
Yes, that was 1921 that book came out.
Yes, and there I was just ready to use it.
Now, is this a suitable place to stop and go and have some lunch?
Certainly. [tape turned off — and then turned back on] Ok, this is after a break for lunch. Before lunch you were discussing a meeting that you recall between Raman, Fowler and Russell at the British Association meeting, 1924.
Yes. That's right.
And you had that very interesting anecdote, that Fowler had made. Now, after this time, could we sort of progress and talk about your association with Russell Primarily? You do not recall really whether he approached you, or if it was the other way around?
Oh, I wouldn't know. We might have just got together on some occasion, social occasion or anything else, and talked about what we were doing. He might have said, "Well, how about taking some pictures for me?" or something of that sort, you know. It might have happened that way. I can't remember.
Did he come to your laboratory?
Oh, he used to come over there. Oh yes, sure. He used to come over here.
And did you see him in the observatory?
Occasionally, yes. I used to go over there occasionally. Not very often, but I did go. And after he died, I went over to go through the whole of his collection of reprints, because they didn't want them at all. They were throwing them all out. So I got a lot of reprints that I didn't have, see, not just of his papers, because he collected reprints of spectroscopic papers of all sorts. So I have a very very big collection of them.
Are any of these annotated by Russell?
Yes. Occasionally they are, yes. I think I have some annotation by Russell about the Saunders-Russell paper.
I'd be very interested to see that.
Let me see if I can't — I'm not sure that I can find things right off the bat, you know, but I might find some.
OK, we did find your file on those, but we didn't find any annotation in those papers.
No, If I run across any, I'll let you know.
That will be fine. Now, we've already discussed the paper on quick method of reducing prismatic spectra. This was sort of characteristic of Russell, to look for efficient reduction techniques.
I used it from then on, myself - never used anything else. Much the easiest way of doing it.
In your discussions with him at that time, within the next year, Russell, yourself and L.A. Turner, brought out the "Report on Notation for Atomic Spectra."
Now, I understand that this developed at a particular meeting.
Yes. I've just been writing it up, actually. Well, there's a copy of it here somewhere. It's here probably.
I have some xeroxes of that paper.
That's the paper, and I can show you some of the original letters.
Oh, that would be very valuable.
They have copies of them at the AIP.
Do you discuss how the team of these particular three people, you and Russell and Turner, were chosen to — ?
Oh, I think they chose us because there were three of us in one spot, and all three of us were interested in the subject.
And especially as Russell was here and very interested in it. He may have — I don't know who introduced the subject, but a group of people I think were called together to discuss this problem. Here are some of the letters, that's King, that's later, though, and that is Thomas S. Kuhn.
These are in the sixties.
Those are. Now we're back, this is a letter from Gibbs.
Here are all the names of all the people we communicated with.
This is May 9, 1928. And he was writing to you. Were you pretty much the person people contacted?
Yes. Yes, I was the secretary of whatever you want to call it, in the group.
That letter is just full of names. That looks like Bowen?
That's August 14, 1928.
Yes. These are all the ones. That's DeBrine.
From Allegheny Observatory.
This is Burns, Steven T. Burns. You've heard of him, I guess, haven't you?
Yes, he succeeded Schlesinger when Schlesinger went to Yale.
This is Catalan.
Catalan, yes, addressed to all three. 7th August 1928.
To the three of us, you see. At that time, I didn't know Catalan. Later on I knew him very well, but, he was a most charming person.
How did the basic notation develop? How did you get together and discuss?
Well, I think it tells in that paper fairly well. This is Karl Darrow, a typical letter from him. That's Gibbs, and that's Grotrian. This letter is in German. It's not signed, but I's pretty sure it was Hund. Then this one, this is Kiess from Meggars. This one is Paschen, here's Paschen's signature.
This is Pauli and Kronig. This is Ruark. And this is just, oh yes, —
Urey and Ruark together.
And they wrote up a position paper, "Standard Notation in Atomic Structure."
Yes. And then this one — oh, is that Sommerfeld?
Yes, Arnold Sommerfeld.
This is Tait.
John T. Tait. And here's another on from him, and this is Peerenbohm, who ran a publishing company. Well, as I say, these really ought to be in a museum, these letters. But I sent them up to the AIP for them to make copies.
They made copies of these? OK. Well, as long as I know that then I know I can find them.
Yes, you can find them up there. Pauli was mentioned there. Did you know that when the paper was published by Goudsmit and Uhlenbeck on the magnetic moment of the electron, Pauli refused to believe it, and for part of a year, went around trying to convince other people it was impossible.
I didn't realize that. Well, this was in the early twenties?
This was '25.
How did you meet with Russell and Turner? What kind of organization did you have? Did you meet at specific times for developing this?
I don't think we were ever terribly well organized. We just got together when we felt we had something to talk about. What we actually did was to go over all the old forms, you know, if you just take.......
Fowler's report on line spectra?
Yes, and here's ....
You're talking about the old spectroscopic notation?
Yes. That's .... These two books, which came out almost at the same time, there's hardly any — no, that's not the one I want, it's this one — there's hardly any agreement on notation in them.
Which two books are these now, Fowler's?
Paschen-G"tze, and Fowler's. This was the German Bible, this (Fowler) the English one.
I have Fowler's book, but I don't have the one by Paschen-G"tze.
The title is Seriengesetze Der Linenspectrum and it's in Berlin, Julius Springer, 1922.
OK. Oh yes, just a year after. Paschen-G"tze was nearer to what we recommended, but the numbering of these — these numbers here are not the proper quantum numbers. They're always in the wrong order.
You're looking at page 65 for cesium. You mean the D1, F1, D1, F2, D2, F2, D1, F1, the quantum numbers?
Yes. Let's see, here are the three of, here the two. You see, here's one of the troubles: there's nothing to indicate there what kind of a series this is, whether it's doublet or what not. Of D1 and D2, D1 should be the lower one, and it is, that's correct there, unless that term is upside down. But, you see, it's very difficult, because in none of these books did they put term tables. You have to get it from the line lists.
Here, however — see, here's calcium, and he differentiates capital letters for singlets and small letter for triplets.
This is in Fowler's book now. Page 124-125.
Yes, this is Fowler. That was more or less standard. Then there are things with primes on them.
Yes, I see them.
What those meant, I've forgotten.
Yes, double primes, and all those things that you had to decipher from reading the other parts of the book, you know. There was just — here, Greek letters.
Right, pi and delta and sigma.
Doublets were given with Greek letters.
So this was a difficult system to be able to —
— Well, there was just no uniformity at all. People had developed different systems, and non of them were capable of taking in all of the developments; as one went to higher multiplicities, for instance, you had to have some way of making it clear what multiplicity you were using. Now, the paper that we wrote was used by the vast majority of spectroscopists for a long time. It no longer is, because the developments have got to the point where it won't handle them, so we had to change notation — well, really, add to the rules that we laid down, so that you can take in all the modern stuff.
How long did it last in the form in which it was presented in 1929?
Oh, I think right through the thirties, more or less.
Certainly. But the basic structure is still used, only it's been added to.
The basic structure is all right. The way in which we said a term should be described, that is, with a capital letter for the name of the term, with a right hand superscript for the multiplicity, a subscript for the J-value, and one other thing, a little "o" above, if it was an odd term. That is, we separated the even and odd, and the odds always have a little "o" over them. That still is used pretty regularly, but some people have given it up, where it's perfectly obvious which terms are odd and which are even. But it makes life much easier if you have that to tell you. You don't have to sit down and think: Well, now, what does this stuff that comes in front of this mean? Does it mean it's an odd or an even term?
Did you correspond with Fowler also? Or you just didn't receive a reply from him?
Yes, we corresponded with him, but it's my recollection that we didn't get anything from him of from Paschen. Well, we did get from Paschen, yes. But I don't think we got anything from Fowler.
Were there feelings of being upstaged?
I don't think so. I don't think so. I never had any idea that there was.
Russell's name appears first here. Is there a reason for that in this particular?
Well, he was a little senior to all of us.
And that was it. You acted as secretary.
I would think so. Yes. Actually, it's in alphabetical order, Russell, Shenstone, Turner.
I think that may be what it was, too.
Do you recall what the different contributions of the three authors were?
Well, I think Russell and I were the main contributors. Lou Turner was not a practicing spectroscopists, but he was a very very good critic and a very intelligent person, and I think he had a good deal to do with getting things settled into proper form. He's dead now.
I know you had at least two more papers with him in the thirties, but before we get to those, could I ask you just for general recollections of your association with Russell during these years? How often did you see him? Did you socialize with him? What was it like to do that?
It's hard for me to remember when I did certain things, but I recollect on several occasions being in his house. I don't think I ever went there for a meal. I might have been there for tea or something like that at times, but I do remember that he'd been a stamp collector. I had too, and we talked about stamps some. He had a collection somewhere, which he couldn't find, and I was desperate to get hold of it. He certainly would have given it to me, but it never was found, and even after he died his wife never found it.
I've not seen it. I've been going through his things.
No. I don't know what happened to it.
What were some of his other interests? What was his house like?
It was a very old fashioned house, you know. Very old fashioned. They were both really sort of 19th century people, in a way, you know. Very — Russell was a very innocent- minded person, very innocent-minded.
Can you expand on that?
That's just the impression you got, that he had no idea of literature that was not just so. I think — you see, he — well, you've got to remember that even when I was growing up, the mention of sex was just not done. When he was growing up, it would have been even less. He never would have had any connection with it except through other boys and I doubt whether he had that. So, it was a very godly family.
A very godly family, right. You mentioned that, at lunch, Russell most probably believed in a personal God and was very sincere in these Sunday evening discussions.
Were there any of his students or colleagues who were close to him, who followed these Sunday evening things continually?
That I wouldn't know. They never had very many students, graduate students, there. We didn't have very many in physics really. In the twenties, we never had more that about perhaps five or six graduate students here at a time. There was some other thing I was trying to think of .... He was, by the was, a godfather of my son's.
How many children do you have?
And how did he come to be selected? You selected him?
Oh yes. Sure. Well, my son was very well looked after when he was christened, because his mother is in the English Church. I was a Baptist. Russell was a Presbyterian. His godmother Eleanor Colt was a Methodist. My son's godmother was a Methodist — and his nurse was a Catholic.
That's quite a combination.
Sure. I'm not sure there wasn't — oh yes, he was christened by a Congregationalist.
That's marvelous. Did you serve on any college committees with Russell?
I don't remember ever serving on a committee with him, no. No.
So you're not too aware of that aspect of Russell's work.
No. I would think perhaps he wasn't used much on committees. He may have been, but I don't know. He used to speak in faculty meetings whenever he felt like it, and he had strong notions about the faculty.
Could you recall some of them?
Well, he was convinced, and I think this has been corroborated, that while Woodrow Wilson was President of Princeton University, he had a stroke. Russell said he was sure of this because he remembered a case where at one faculty meeting the President had made a statement — at the next faculty meeting, quite an opposite statement.
I know that Russell's politics and Wilson's were very different. Do you?
Well, you've got to remember that this was true of the whole Princeton family here. It was a complete break between the followers of Wilson and the followers of Andy West, and that went on for years after both of them were out of circulation here.
Do you have any stories about Russell's direct association with either West or with Woodrow Wilson?
No. I know this feeling ran high. For instance, Dean McGee was one of the opponents of — well, he was on West's side, so therefore against the ideas that Wilson was putting out. When Wilson was in the White House, he had a dinner, to which he invited all the members of his class of 1879 except two. One of those was Dean McGee. The other was Parker Handy, both of whom were opponents of his.
A bit of a boycott.
Did you continue contact with Russell after the thirties and through World War II?
Yes. Oh sure, because after World War II, when I came back, I was again away all through that war, the first meeting we had was at the Bureau of Standards. I guess it was an informal meeting - it must have been. Condon was then head of it, and the group of us who were interested in spectroscopy, including Condon, were talking about promoting work in spectroscopy, and we decided to form a committee, which still exists, the Committee on Line Spectra of the Elements. Russell was the first chairman of that committee. I was the second.
This committee had Charlotte Moore Sitterly?
Yes. Yes, she was always influential in it.
Oh, all of them. Meggars must have been — no, he may not have been head of it at any time, but he was always very active in it. Yes.
Right. How was Russell chosen to be the first chairman?
Oh, he was always the prime mover. And he was obviously very interested in getting this sort of thing going, because he realized the necessity of having much more information from the spectroscopists for the astrophysicists.
How do you think his attitude was towards laboratory spectroscopy? I know he always supported it extremely forcefully, but did he always see it as an applied field to his own interests, or was he interested in it, in its own right?
No, I think he was interested in it for its own right. I think that becomes obvious when you look at some of the things he worked on.. Nobody at that time, at any rate, could have thoughts of gadolinium as being of any interest to any astrophysicist. But that's on of the remarkable papers he wrote, you know.
He was working on gadolinium even into the 1950's?
He published a long paper on it. First time that anybody had found such high multiplicities.
So in every aspect then he was working as a laboratory physicist or astrophysicist?
Not as a laboratory physicist, because he never took a picture. And everybody who ever knew him as an astronomer said he was a very ham-handed astronomer.
I didn't realize that. Tell me some more about it.
Well, all I — that's hearsay as far as I'm concerned. But someone in Cambridge was the first person who told me that, that when he went there, he was a very very bright fellow, but he didn't know how to handle any apparatus.
Hinks was already gone from Cambridge by the time you were there? I believe he left Cambridge.
His name's familiar, but I guess —
He was the fellow that Russell worked with initially on parallaxes.
Yes, well, that would be —
It would be interesting to know who you heard that from at Cambridge.
I don't know.
OK, well, that certainly does fit the type of work that Russell did. He always had the most appreciation for the value of observation and what was good observation.
But he never did any of it himself.
Oh no. No. He was a thinker, not on the sort of fundamental scale of Einstein, but on a pretty fundamental scale in astrophysics.
How did he get people to do things for him though? Because he needed observations. Did he come in and say, "Well, I think you should do this?" Was he authoritarian? Or did he discuss things with you?
Well, that committee —
— the postwar committee —
Yes. That used to discuss what things ought to be done. What was going to be necessary in the near future for astronomy especially, because obviously astronomy is the big user. Yes. And that's gone on and on, because as time goes on, the astronomers have wanted more and more information in the far ultraviolent, way out, and so there's been a great pressure in recent years to analyze spectra of very very high ionization. I think they've got up to something like 28 or something like that.
I remember 14, 15 times ionized iron and things like that, but —
Yes. Well, for a long time, I think the highest one was 19 times ionized copper.
Well, you know, I may be wrong about that, let's see, copper is 29, isn't it? I think you'll find that the highest ionization in copper may be the equivalent to sodium. And that's why these high ones were possible in those days. You could do an accurate enough extrapolation through the periodic system, and find out where the main doublets, you know, of a thing like copper 19 would be, and look in that region, and pick out what you think. But there've been a lot of things picked out wrong.
Yes. Well, when Russell began working, I know that he had a lot to do with the early identification of multiplet structure.
I guess multiplets defined as Catalan did, in the early twenties.
He needed an awful lot of data.
— I was just wondering if he ever tried to pressure you into doing more work or ?
No. No, he didn't. He was very — he never asked me to do any specific work for him. No. I think he was happy enough to have got things going with that committee, and a forum where few people could press for work in particular lines.
Well, going back into the thirties, the two papers you had, in 1932, with Russell, was "Perturbed Series in Line Spectra." That was in the Physical Review, 1932.
And then in '34 with Boyce and Russell, on "Rydberg Interpolation Table." That was published by the department of astronomy and physics here at Princeton.
Yes. I'd forgotten that one. But there's one other with Russell, just Russell and myself.
The 1929 paper? Russell, Shenstone, and Turner.
From Russell's bibliography I found these four publications that you had in conjunction with him. How did you do the "Perturbed Series" paper?
Well, you see, this came about because he had found in doing calcium and some other spectra, that there were series which were obliviously series, but which you couldn't put down a formula for.. And then, having that, we began looking in this book of Fowler's...
In Fowler's book, there is a whole chapter on abnormal series, with no explanation of how to deal with them, and some most extraordinary formulae proposed for dealing with them. I mean, these are some of the formulae he proposed to deal with them.
Wow. They're quite complicated.
Yes. And amongst the ones that are listed here, calcium is one of them, you see.
This is something that had been bothering Russell?
Had been bothering a lot of people. Yes. But the reason we did the paper was that, I think both Russell, Fowler, and myself had been worrying about it and wondering how we could deal with it. This is the paper, here, yes. This is the "Perturbed Series" paper. It's given here at the bottom.
Oh yes, the reference is here.
A deduction from quantum mechanics, that there should be an interaction between a series and other levels of the same character, and Russell gave a rough idea of the form that would have, and we reduced it to the form we used, this form here.
That's in the middle of the page. That's the Ritz formula.
Sorry, that's the Ritz. No, this is the formula we did. And this is the form which comes from interaction.
How was that generated? Did Russell sit down and work with you on that?
You mean that form?
Well, you see, if comes pretty straight from this Langer thing, and inverse variation with the difference between two levels.
What I'm trying to get at here is how you collaborated with Russell. Did you do part of the work and he do a part?
Well, he — I did most of the writing, I know. But we collaborated on the calculations, I'm sure, of the various series. He proposed a good many of them and I proposed some.
Who found the Langer paper? Did you find the Langer paper?
Well, I think somebody, a theorist, it might have been E.U. Condon, who noted it and suggested it to us. And then it became obvious that this was the way to do it, and it became obvious that — this is the sort of curve that you'd find in that book, where they didn't do it this way. But that, that is the way a series looks, if you put into it an extra term.
A vertical dash line.
Yes. That's the term, the level which is doing the perturbing. Now, if you take that out, everything here moves up a whole unit, becomes this. So you've got a resonance.
Yes. This is on page 14, Figure 2. That's quite interesting. Who developed that and was the resonance? Both of you did?
We both realized that's what had to be removed, in order to get the thing right.
There are term diagrams?
Yes. Not only the series went wrong that way, but the separations within these terms, that is the separations between levels within the terms, were perturbed too. And that's explained here on this page, how that came about.
On the following page.
Yes. And then there are tables of the calculation, and that's the whole table of how that calcium one was calculated. This is — that's barium. That's one that Russel certainly was involved in bringing to our united attention. That's mercury, and that one I was the person who brought that up, and that's aluminum. I think I was the one who brought that up too, and this is copper. Copper was so complicated we couldn't really do a calculation, because the two components of this doublet P series are perturbed in different places, by a very wide doublet P here, which, the two components of which fall, they bracket one of the terms of the ordinary P series, and therefore throw them in opposite directions. But that's the — there are many many more than those, of course. These were just the most obvious ones we could find.
That was an exploratory paper really.
In a way, yes. But it showed how one had to deal with them.
During all this time Charlotte Moore, later Charlotte Moore Sitterly, of course, was working with Russell. Did you have direst contact with her on the various projects too?
Oh yes. Oh yes, sure. I talked to her various times. Certainly.
How did they work together? I've interviewed Mrs. Sitterly, but I would like to have your impressions of how she worked for him and what the relationship was.
She was devoted to him, you know. Like most connections of that sort, she probably was in love with him. I don't know. But she certainly was devoted to him, thoroughly devoted to him.
And how did he treat her?
Oh, very well indeed, I think, very much — sure.
She was also very close to his family, so I guess the contact was very —
— yes. Yes, it was. Yes. Well, it had to be, if you were close to him and working with him. Because he and his family were a very, very tight group.
You did say that you'd go over there. He had a study. Did you ever work with him in his study?
No, I never worked with him there. We always worked over here in his office.
There were a number of other people too who were around. Did you have contact with the other astronomers, Dugan, and did you continue with Stewart?
I knew Dugan, but only very slightly. Stewart, I knew quite well, and I had correspondence with him not very long before he died. This is outside spectroscopy, but he did a thesis with O.W. Richardson, on an effect which is always called the Einstein-de Haas effect. It really should be called the Stewart-Richardson effect ot the Richardson-Stewart effect, because they did the experiment long before the Einstein-de Haas effect was ever experimented on.
Then why weren't they given the credit?
I don't know. I never have understood. They not only did a much better experiment, but they surprisingly got for the electron the factor 2 that we know is right, twice as much as it ought to be.
Well, Stewart seems to be a very interesting —
— a little crazy afterwards, you know. He went off into what he called "social physics."
He did that in the thirties?
Well, when did he start at it? I don't know.
I thought it was just pre-war but I'm not sure. He did not get along that well with Russell. I was wondering if you had any comments on that.
I don't know. No. It was a very odd thing that he went over into that department. I never understood that. Because he was a good physicist.
Oh, I see. Is it possible Russell asked him?
Maybe. He must have. He must have been asked. He probably wanted somebody who knew classical astronomy to teach.
But who also knew physics.
Right. I know that Stewart wrote many of the sections on physics for the Russell, Dugan and Stewart volume.
At least he was the one who wrote the original drafts, I believe.
We;;, we've covered a lot of general ground and some of the specific papers, of course. It would be interesting to recall if you know of his attitudes toward the involvement of the United States in World War II. And the war in Europe. He was very pro-World War I, very, very much against Wilson's non- interventionist policies.
Yes. I don't remember about World War II.
Did you leave Princeton during those years?
Oh yes, I was away from Princeton from 1940 to '45.
Where were you?
In Ottawa - attached to the National Research Council of Canada. They sent me to England for most of that time. I was in London for a great part of World War II, as the representative of the Canadian Research Council.
So this was an administrative post that you held, primarily?
Yes. I had an office there. I had to make sure that every new thing that was going on having to do with the was got reported to the Research Council in Canada, that sort of thing. I had meetings all the time. That's how I knew such people as A.V. Hill, who was very largely responsible for getting the British scientists into a position of some authority in the government.
Especially during the war.
Yes. He was a Nobel Prize man in physiology.
I'm not familiar with him.
A very great man. Very great man. Oh, I, my war work, one thing I never touched during the Second World War was spectra - this was a part of physics that nobody wanted anything to do with then, because it wasn't any use.
Charlotte Moore mentioned that she did continue on spectra throughout the war because there may have been some need especially by the Naval Research Lab or others who were looking at spectra under extreme conditions.
And that conceivable could have something to do with examining, let's say, the spectrum of the bomb.
Well, under the Manhattan District, there was work on the spectrum on uranium, right in this building.
Yes, on my big 21 foot grating spectrograph. That was done by Julian Mack. He spent the war years here doing that.
To your knowledge did Russell do any work of this sort?
I haven't the foggiest idea. I was completely out of contact with Princeton, except on a very few occasions when I managed to stop off here for a day or so. I happened to walk into a colleague's house, H.P. Robertson's house, one afternoon, and they were terribly excited. They'd just had word that the Japs had attacked Pearl Harbor.
This was Robertson and who else?
I can well imagine. Well, that was still quite early. You were stationed in Ottawa at that time before you went to England?
Yes. I was doing liaison first, between Ottawa and the United States. And that was quite a job. It involved some difficulties. You perhaps don't know this, but before the war, the government of the United States passed a neutrality act, which said that no war materials may be exported from the United States. Well, now, war comes along, England wants to get aircraft — you can't but them here and fly them out. You have to buy them, and push them across the Canadian border, and then fly them out. That's what had to be done.
Were you involved in that?
No, but I was involved in a thing called the Tizard Mission. Did you ever hear of it?
I'm not sure I know what that is.
Well, Tizard was a physicist, a well known one. In the summer of 1940, he brought over from England, a group of people, with all the new things that had been invented or proposed, for defense purpose in England, and Churchill had asked him to bring this mission over and trade things, quid pro quo. And Tizard said he wouldn't think of bringing it over unless he could just lay everything on the table and say, "Look, here's what we have to give. We Would like things back but that's up to you." What we brought in that mission was of extreme importance - two things for instance, had not been developed at all in this country. One was 10 centimeter radio waves. I saw the first tube handed over.
You know, nobody in this country had ever seen 10 centimeter waves of more than a few milliwatts, and here were tubes that would put out pulses of 20 kilowatts, just suddenly, like that. The other development was this — the chief thing that a bomber had to have in the Second World War was power controlled turrets, so that the machine gunner could switch around from one place to another just like lightening. Well, you know, they rather pooh-poohed this in the American Air Force, but the first time they sent a lot of bombers over Germany without such things in them, it was a disaster. They never tried it again.
These are the sorts of things that Tizard brought over.
This sort of thing. But the 10 centimeter magnetron was probably the most important. But he brought over other work that was being done, and a proposal which had not been thought of over here at all, for proximity fuses for anti-aircraft guns. And, they brought over the preliminary work for the atomic bomb. They brought over details of radar of all sorts. It was called RDF in those days. And they brought with them experts. I remember a Colonel Wallace who had been the expert who had taken RDF control of anti-aircraft guns to France, and had to dump them, at the evacuation. And they brought over a young man named Bowen who was from TRE, that was the Air Force Telecommunications Research Laboratory, who, I was told afterwards by the people that worked at the Radiation Laboratory, had all of the ideas that they used and developed, in his head.
Oh, there were a lot of other minor things that turned out to have some importance, you know. They brought over, for example, all of the plans for a battleship weighing two tons.
The plans themselves weighed two tons?
Two tons worth of paper?
Well, this was certainly a very important mission, trying to bring these —
It was a mission that was hardly understood in this country at all. It was of extreme importance, and it was extremely generous.
How did the United States respond?
Very well indeed. Oh, they fell all over themselves to give us anything that they had that would help.. Oh yes. And the Bell Labs immediately produced and worked on these magnetrons.
You said that the Naval Research Lab at MIT was built —
— not the Naval. It was called —
The Radiation Lab?
The Radiation Lab at MIT was founded in the summer of '40 specifically to develop the use of the 10 centimeter magnetron, and before it finished it was employing thousands of people. Two of the chief parts of it were controlled by people on the faculty here. One of them was Lew Turner. The other was Milt (Milton) White. Milt White had charge of all of the airborne developments, and Turner had all the ground developments, like anti-aircraft control and that sort of thing.
I've talked to a number of astronomers who, during the war, worked at the Radiation Lab.
Yes. They got very good staff.
Yes. I was quite interested to see just how versatile the astronomers were at adapting to work in electronics.
And things like that. Did you ever have any contact with astronomers in Britain or elsewhere who were working in the war effort?
A little, yes. I don't know specifically of any particular ones. I did have something to do with the Canadian who was the astronomer at Oxford.
Plaskett? H.H. Plaskett?
Plaskett, yes. I'd know his father and his uncle. His father was an astronomer, but his uncle was the head of the shop at the physics lab in Toronto.
I think I recall that. That's how H.H. Plaskett originally got interested, was in his father's shop, I think. I did have a chance to talk with him at Oxford, for a very short length of time about a year ago. And did not find out anything about his wartime activities. You don't —?
No, I don't remember. I remember after the war talking to him, or after the war was finished, or maybe just late in the war, about some spectroscopic problems.
He was a solar spectroscopist.
Yes, I know.
Let's return to Princeton, after the war, I know that during the war Russell had some form of breakdown. He had had a stroke or something.
Yes, perhaps so. He didn't seem to have been affected much by it when I knew him after the was.
Oh, he was the same?
Oh yes. I didn't notice any difference.
But it was very close to retirement for him. I guess he retired in the late forties, 1947, 1950's.
I could think so, yes. Let's see, what class was he in? Class of '97 or something like that?
Yes, that's right.
'97. If he was 70 that would make him —
He was born in 1877. So that would have made hi 73 in 1950.
Was there compulsory retirement?
Yes, there was compulsory retirement at 68. Yes, so he probably retired at 68.
Do you recall any ceremonies or anything acknowledging his retirement?
I don't. No. Let's see, if he retired at 68, when would that be? 77 plus 68 —
Well, '60 would be 1937, and 8 would be, '45.
Well, I wasn't here.
That's right. I'm not quite sure when he retired. I thought it was just possibly a few years after that.
I think you'll find that he probably retired at 68.
That was a very hard and fast rule?
It was a very hard and fast rule. The only way it could be broken at Princeton was that a man could be kept on one year at a time, for some very special reason. I know for instance Dean McGee was kept on to act as Dean of the Graduate School because the man who was the dean had had a stroke. And they had to have somebody in a hurry to look after it.
What are your recollection of Russell through the 1950's up until his death in '57? Did you maintain contact with him?
I did, in a way, because of that committee, you see, and whenever we got together we'd discuss what the state of affairs was. But I don't remember anything specific. It was probably during that period when I sat in his office in his house and we talked about his stamp collection. It probably was at that period, yes. Tape #3, side 6
If you were to sum up your general recollections of Russell and his association with you and with Princeton, how would you form you thoughts?
Well, I would say that it was a very fortunate thing for me that he was here because he was by far the most interested in what I was doing.
Yes. There was some considerable interest in the faculty here, but there wasn't anybody here who was working in it except myself.
Do you think that you would not have gotten the original Hilger spectrograph if it wasn't for Russell's interest?
Oh no, no. No, that was promised me by the department. But that reminds me, under this box is a measuring micrometer which really belongs half to astronomy.
Could this be one that Russell had used himself?
Oh yes. It was bought when Russell arranged to have the astronomy department pay for half of it.
I'd like to be able to get a picture of that sometime.
Oh, you can.
You mentioned that he didn't do observation, but he certainly did do measuring?
Oh, he could do measuring, yes. He did measuring himself. I was too busy measuring my own things. I didn't mind taking pictures. I've taken pictures for so many people, I can hardly count them.
While Russell was measuring, he was over in astronomy when he did that, you didn't have contact with him?
No, at that time the only instrument for measuring a plate was over here.
So were you with him when he measured?
Not always. No. I was probably in my office over here.
To your knowledge, could he measure for very long periods of time without a bread? Was he intense about ir or did he take a lot of breaks?
I don't know. I would think not though because it's pretty trying work.
You think that he didn't go for long periods of time.
I've measured star positions and spectra myself, but not over long periods of time. I'm just wondering abut how he reacted to repetitive physical work like that.
I would think that he didn't do it for any great length of time. I don't know. I wouldn't be able to tell. It was through Russell that I got to know Catalan well. I didn't know Catalan till after the Second World War, and then I knew him very well. He used to come to work with me here.
Yes. Well, you'd had contact with him ever since that paper on notation he'd written.
Oh well, yes, but you know, a very desultory correspondence. But it was after the war that Russell had formed a close contact with him over the iron spectrum. Catalan had need working at it for a long time too, throughout the war, you know.
Yes, that's right. Well, I was asking you about general impressions of Russell. Have you pretty much —?
I think I've given you all the general impressions I have. I was just wondering whether I have — what I have here in the way of — that's a manuscript of my war years, but I don't think you can read it.
This is World War I. Are you discussion with a publisher the publication of these?
No. I started out to do it for my family, and I'm not sure it's suitable for publication.
Would you consider depositing it at the American Institute of Physics?
Well, if I ever get to the point of having it duplicated in any way, yes.
Even the rough copy. Even the rough draft copy?
Well, if I can trust you, here's the typed copy of that period. I think it's not absolutely complete, but it may be nearly so.
But that's the only copy there is?
Yes, that one over there. Oh yes, this is the only copy there is. And it's very badly typed. All sorts of mistakes made in it.
About the only thing I would be able to do is xerox it somewhere.
You wouldn't want to do that?
Not yet, no. No, I don't want it xeroxed yet. Until I get further on with the whole thing.
Well, it's a very difficult task, writing an autobiography. I can appreciate it.
Oh, it's a horrible job. But fortunately for me, for that part of my life, the years of the war, I have a book — it's the history of the division I served with — which tells me where I was at different times.
The 7th Division, 1914-18, by Atkinson, C.T. Atkinson, London, John Murray, 1927: that's a valuable book to have.
Yes, it is.
The statement in this book that is really astounding to me, even having been with the division for all that long time — yes, I'm looking for the statement about the total casualties the division had — it fought from the fall of 1914 to the end of the was, and during that period, it had 85,000 casualties — a division, you know, is about 20,000 men.
85,000 casualties out of 20,000 —?
Well, 20,000 yes, but of course they were renewed, after every battle. I mean, after the Battle of the Somme, they probably lost, I don't know, they probably lost 5, 6, 7 thousand men. They would all be renewed.
This figure would include all casualties — they might be small casualties or not. More wounded than died, of course.
Yes. Dr. Atkinson was in World War I also?
He'd had quite an experience, as I recall. In fact, he came down with a rather serious illness, I don't exactly remember what it was — but I'm sure he pulled through all right.
Yes. Well, I was fortunate in being in the Royal Engineers, because we didn't have the casualties that the infantry did.
Right. But you were right there....
Oh yes, I was right there.
Well, I don't want to take any more of your time this afternoon. It would be nice if you —
Well, if I run on any writing of Russell's, I'll let you know.
Thank you very much.
Before you go, write your name and where you are and your telephone number and everything on a piece of paper for me. My memory is terrible.
Sure, absolutely. ...Did you have contact with Babcock?
No. I don't know. I've met Chandrasekhar but that's all I can say. Fowler, I think, was a graduate student here. I'm not sure. Friedman —
Yes, I wonder where he is?
He's in Washington, D.C.
Yes. I think he was at one of the Naval Laboratories or something like that.
I believe so. Yes.
Gingrich, where is he?
Yes, Leo Goldberg, yes....no those are the only ones I know.