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Interview of Edwin Kemble by Thomas S. Kuhn on 1962 May 11,Niels Bohr Library & Archives, American Institute of Physics,College Park, MD USA,www.aip.org/history-programs/niels-bohr-library/oral-histories/4702-1
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Transfers from Ohio Wesleyan to Case. Works for Chase Machine Company. Enters physics. Research with Professor Miller, instruments used, experiments performed. Describes his coursework, graduate thesis, and mathematics at Case. Mentions Miller's research. What was known and discussed about the quantum and Millikan's unitary theory of light at this time. At Carnegie Tech. meets Knox and Hauer and runs the freshman laboratory. Describes the atmosphere at Carnegie. Begins a fellowship at Harvard in the fall of 1913. Studies under Wallace Sabine, Osgood, Maxime Bêcher, and B.O. Peirce, Bridgman, and Harvey Davis. Mentions Duane. Discusses the physics and mathematics departments at Harvard. Bridgman's potential theory course discussed. Describes unsettling problems in physics during this period. Harvard's weekly colloquium. Thesis and collaboration with Jim Brinsmaid. Ideas he had about future research topics. Classical emissions. Bohr atom as appreciated at Harvard and the reception of quantum theory following the War. Complications in physics at the time of the interview. Instructs at Harvard after the War. Researches helium spectrum, band spectra, integral pdq equaling nh. Visits Germany in 1927, his readings in German physics. Mentions his Ph.D. student, Van Vleck. Hamilton-Jacobi techniques. Discusses theoretical physics before quantum theory. Describes Duane, his research, Duane grating theory. De Broglie's paper on the wave properties of the electron. How the discovery of the Compton effect was perceived at Harvard. Webster, Webster's career following quantum theory described. Mentions the backwardness of theoretical physics and mathematics in the United States. Writing his book, his work on general education explored. Mentions his bibliography. Included is a letter from Kemble detailing his first references to Bohr.
Could we start with college and university education in physics.Which I guess really for you would mean Case, rather than the year at Ohio.
Yes, Ohio Wesleyan didn't count toward this.
Who was at Case when you started?
Well, Dave Miller. But I didn't go there with the expectation of studying physics. I was a minister's son. I went to a denominational college first. My older brother was an engineer just starting some work on steam-turbine tests. He was a practical-minded person and suggested that if I would leave Ohio Wesleyan and go to Case, if I graduated that I would have a profession and be able to earn a living. Whereas that was quite problematrical if I went to Ohio Wesleyan. So I went up to Case as a sophomore and registered as a mechanical engineer,which happened to be my brother's field, and it seemed reasonable. After my sophomore year funds gave out, and I had to take a year out of college. And during that year I worked, actually under my brother, as an employee of the Chase Machine Company, doing the computing that was necessary to analyze the results of stemturbine nozzel tests that he was making at the mechanical laboratory at Case. This wasn't a very commercial enterprise really. It grew out of an invention of my father's. And my older brother Tom was putting some real engineering into the minister's invention. But there was just enough of something that was engineering and not real science involved so that I came away from that year with my mind definitely made up I would not be an engineer. If Cleveland had had a school where there was a good course in biology, I would have gone to that at that stage of the game. But I figured that if I went into biology — I had a childhood interest in entymology— that I'd have to go out to Chicago, and this was too far; I couldn't afford it. They had a good scientist on the Case faculty teaching physics, and I had done very well in my sophomore physics. So I did go into physics, and I had things so to speak all to myself. At that time Professor Miller had built up an excellent collection of classical physical instruments, standard instruments, standard electrical instruments. We had one of these (Rieffler) clocks in the basement. It was a showpiece. Put one kilogram on top of another if you could do it, and it was sensitive enough to show change in weight by change in distance from the center of the earth. It was a beautiful, new laboratory. He had one student in each class for a number of years, including the years I was there. When I entered physics as a junior there was a senior, and when I became a senior there was a junior. The two students in the department of physics had the run of the building, their classes were held in professor Miller's office, and we read books like Wood's optics together and talked about them. This was the course. Every afternoon I was loose in the laboratory with a key to everything. And I picked one experiment after another; Gray's absolute measurments in electricity and magnetism, (Tippler's) shadow photographs of sound waves, (pre-Foley) days, I set these things up, in some cases collaborating with the other student, in some cases by myself. I did the experiments, made records of it. And went back to the shelves and talked to professor Miller about what would be another good experiment to do. And so, with the slightest superintendence, I just tried out the instruments, and got along very nicely in this.
Do you remember what other books you looked at?
Oh, not very definitely at this time. Of course Miller was very much interested in sound. Barton's textbook on sound was one that we used. I had a lot of engineering courses in parallel. There was a course in mechanics and materials and hydraulics and a course in electrical engineering theory. There was a course in probability — least squares, I think it was called — not probability. This was a useful adjunct. Then for my thesis I got interested in — well, in the math department, in Fourier series and spherical harmonics and in Miller's (phonodeik), which he was just developing. This was a mechanical scheme for picking up sound waves and converting the wave form into an oscillatory motion of a beam of light and, with a film moving by at a uniform rate, getting the shape of the sound wave. There were problems. He wanted to avoid resonance and get a true picture. And he used rubber bands to apply tension to a string that was in the picture. This pretty much killed out the resonance effects, which was good. But just exactly what was it doing? I tried inventing a crude theory of how viscosity might work. I didn't study very much of what anybody knew about this kind of rubber viscosity but just guessed at something and then put the Fourier analysis to it. And that became my thesis. I have one recollection here that is very vividly in my mind. Namely, that there was a period of about a week in which I had a burst of ideas about the design of this machine and how it might be operating. And every morning for that week I went into Miller's office with a new idea. an idea which meant enough to him so that he was really interested, and the one thing was following up another. It left me with a vivid sense of the way in which mental activity propogates itself. When you get into this state of intense alertness, with these ideas plowing around in your head, you become at least five times as bright as you normally are. And that probably is an understatement. I had such periods occasionally, later on, but I think it's important for scientific people to realize how much it means to a graduate student to be assigned a topic that he can get excited about and to have a break somewhere in the picture. Wheeler Loomis, who was to become an outstanding figure in physics in this country and Chairman of the present physical society, had the misfortune to get a doctors' thesis here at Harvard on the specific heat of mercury vapor. He didn't like the subject. He couldn't get himself interested, and so his thesis was a labor, a choir to be got through with. He never did get going for years afterwards with the mind that he had. I just thought he got a raw deal from the nature of the many persons — —
How far did math go along with this?
Well, I had an elementary course in differential equations, ordinary differential equations. And then I had this work in partial differential equations. And I can't remember now — I rather think that (Ted Focke), who was chairman of the math department — I probably took this Fourier series work with him. But again it probably was more or less individual because we had no math concentrators. It was an engineering school, and everyone except the two physics students was enrolled in one of the normal branches of engineering.And they didn't go very far with mathematics. The professor of eletrical engineering, under whom I studied in my junior year, was very slow at mathematics. And I sat in the back of the room, and while he was taking fifteen minutes to go through some piece of analysis I'd work it in five minutes with my mathematics. And I didn't take any notes. There wasn't anything to be done, it was so elementary.... It wasn't prevalent in the school. It was still in the days when engineering was primarily cut and dry. There's been a big change in my lifetime. Well, Miller was a member of the National Academy and a very highly respected person— properly respected — but a pure experimentalist. I got a great deal out of this. I graduated in 1911 and went to Carnegie Tech as assistant instructor in physics.... Miller was not working with the Michelson-Morley experiment at that time. He had worked at it, we heard about it, and I think he went back to it later on. And I had, later, quite a good many talks with him about this. I remember he got out a long review in Reviews of Modern Physics at a later time. And he found this residual effect that seemed to defect a particular direction of motion of the earth realtive to the aether, and it was one that made sense in terms of the position of the sun in the gallaxy, just scaled down.
When you were there at Case as an undergraduate, did the problems of modern physics come to your attention at all? Were you aware of the quantum even, do you think by 1911?
No I wasn't particualrly aware. I'm trying to think. I remember a paperby Millikan on what he called the unitary theory of light. (I've always puzzled since.) He meant the photon theory, but he called it unitary. And I have a feeling that there may have been a meeting of the physical society at Case, and that he gave that paper there, and that I heard it. But, I'm not sure whether that's so or not. I know that I wasn't thinking in these terms while I was at Carnegie Tech, which was two years. I went there, I think in the same year that Clinton Davisson did. But I was trying to get fully under my belt a good understanding of classical physics. When I graduated I took an examination for the Bureau of Standards and was offered a job.... But it looked like the opportunity at Carnegie Tech was a little bit more interesting. I took it, and I had a great deal of responsibility thrown on my shoulders immediately as it turned out. The head of the department was an Englishman. Seems to me his name was Knox, though I can't remember for sure. He was ill so that I saw almost nothing of him during the year. Next in command was (Hauer), Happy Hauer he was called. I reported to him. But they had a big freshman laboratory,and they put me in charge of it. And I just worked out my own salvation. I didn't develop new experiments, but for the experiments for which they had the apparatus I wrote directions, type-wrote the directions and put them on a cardboard and shellacked it, and left these shellacked directions around.
How many other people were there teaching in the department at Carnegie Tech? This was the physics department?
This was the physics department. Carnegie Tech was just getting going. It had been in existence three or four years, I would say. I'm not exactly sure, but the paint was still fresh, and the policies were not yet well defined, and there was this excitement — freedom — where they had new buildings and enough money and were trying to work out their salvation.... There was Knox and Hauer and (Grondall) and Davisson and myself. And that's about all I'm aware of in the department. We had a German mechanic to do things with the apparatus for us. But as I remember, the first year I was totally occupied with this laboratory. And totally free to do what I pleased, and I enjoyed myself. The next year they gave me a class in physics to teach in night school. And I had a good deal of pleasure in that. Then after two years Miller wangled a fellowship at Harvard for me, and I came here.
Had you had much time while at Carnegie to go on with more advanced physics?
Not very much, no. I had done some work with the Army engineers in the Cleveland harbor when I was an undergraduate. And I think it was the summer after my second year that I worked on the dam in the Ohio River down below Pittsburgh as an inspector, and this wasn't too arduous. I bought a copy of Jeans' Theoretical Mechanics and spent all the time I could get during the summer working problems in that. These problems in mechanics turned out to be analytic geometry in disguise. But this was the thing that was fresh on my mind when I came to Harvard in the fall of '13. Wallace Sabine was the friend through whom the fellowship came, and I discovered afterwards that he had paid for my fellowship out of his private pocket. I took optics with him, mechanics with Osgood, a full year of classical mechanics, and also a full year, the first year, of theory of functions of a complex variable-half of it with Maxime Bocher and half with Osgood, and that was a very big mind-strecher for me. Then I began a course in potential theory, both gravitational and electrical, under B. O. Peirce, who died in December. The rest of the first half-year was completed by Osgood, I think. From then on I began working with Bridgman in electrical theory. The big thing the first year gave me was contact with people, especially Osgoodand pierce and Bridgman, who are thorough-going in their rigor of thought. And I got the idea in my head that if you really understand a subject, it meant that there were no if's, and's, but's or guesses involved, and that any subject that was properly straightened out could be understood by anybody, if he had enough time.
Did Osgood teach mechanics in the physics department or in the math department?
The math department.
And the potential theory course; was that also in the math department?
No, well, it was taught here in Jefferson laboratory. It first straddled the two departments. He built up the electrical laboratory, which would be now a junior electrical laboratory. Those were the days when each experiment was built up, and then a box was built around it, and it was covered and locked, until you needed it the next time.
Was there also mechanics given over here, or was the analytical mechanics pretty definitely a subject for math?
It was certainly given in mathematics, it was an undergraduate course, Math 4, and this graduate course, Mathematics 8. It was I who began first, I think, to teach mathematics in the department of physics, quite a little bit later. I guess the main reason for transferring the teaching of mechanics to physics was that as the quantum theory developed, there was need to get good training in the higher principles of classical mechanics. Also, at the same time we felt the increasing pressure of more things to be learned. We just couldn't see anybody taking as much time with the very elementary parts of mechanics as had been the custom in the math department. One needed to have it taught by somebody who knew what it was going to be used for later on. So it got shifted across.
When Bridgman took up the potential theory course, did you get Maxwell's equations at this point?
Well, I'm a little confused. I ought to get out my old notes, which I still have. One of the things that I bean to do when I came here, was to write a textbook for every course that I took. So when it came to teaching graduate courses, which I did as soon as I got my first appointment here, the first thing I got was the textbook that I had written on the basis of Osgood's lectures or B. O. Peirce's lectures or Bridgman's, as the case may be.... I still go back occasionally to my notes on the mechanics course, which were kept in a very compact style; they had to be. But we had two courses, Physics 9 and Physics 10, as I remember it, and for some reason or another, Physics 10 began as potential theory, and went on to electrostatics, and Physics 9 was the course in which current electricity and electromagnetic field in general were taught. And these were successive years. All of the more advanced parts of electricity and magnetism I got from Bridgman. It was his first time around, and it was wonderful, the way he did it. I got an immense sense of security about all this material. I never understand how people can have, now, the same kind of sense of security, that haven't struggled with displacement currents and the Thomson effect and the Peltier effect and all these things that are a part of the complete picture. I don't know exactly how far that first course went. It may be that Physics 10 was a half course only, that I took in the fall semester. Perhaps I took something else in the spring. And then what I call 9, which is really the more advanced of the two, was a full course, a year later; something to refresh my mind about.
Was Duane here then?
I don't believe he was. It seems to me that he didn't show up here until after the war. The other person that I recollect best is Harvey Davis. I saw a good deal of him. He was a contemporary of Bridgam's. I studied thermodynamics and especially Gibb's work on chemical thermodynamics with him.. I don't remember doing this paper on — wait till I find the place... This is Gibbs'collective papers and — "An Essay on the equilibrium of heterogeneous substances." That was a tough one, which I worried through under Harvey Davis' tutelage. Again I don't remember all about it. But I've got a lot of respect for the amount of mathematics that can be put in a book without writing down any equations! That's Gibbs. You had to get out your paper and pencil and sweat to see what the sentences meant.
Well, Ted, let me ask the same question now that I've asked before with respect to Harvard. Did you now begin to get a sense of the existence of really unsettled and unsettling problems?
I think as a graduate student I didn't have a sense of responsibility about these things — to say to myself, "Physics is in trouble." But although everyone in the physics department was doing research, they were engaged in kinds of work that didn't involve this sense of being in trouble. Except of course there was spectroscopy. Lyman was engaged in his ultraviolet spectroscopy, and there wasn't any understanding of what all this meant. This everyone was aware of. Bridgman was starting his high pressure work, and of course this is a kind of purely empirical material. His analytical mind was engaged in clarification processes on older theories. But the ideas that were revolutionary were coming from Europe of course. We had a weekly colloquim that everybody went to; I never missed a session to my knowledge. I'm sure there was a full presentation of these various things as they were coming along, and yet I can't tell you what proportion of the talks that were given on things like the Bohr theory of the hydrogen atom. We certainly were aware of it. My Thesis grew out of ideas that came, I suppose, originally from such a colloquim. I got interested in my third year here as a graduate student in the Bohr theory, and tried making connections with other parts of physics. In particular, I knew there band spectra and infra-red. The first idea was that if the Bohr theory was right, then molecular vibrations must have a minimum amplitude which is pretty large. If there is then absorbstion of these vibrational motions, we must have the situation in which the amplitude is big enough to strain the simple harmonic motion picture. There ought to be some harmonics appearing. So that's the thing that I got started at.... what happened was that I tried to work out, given the size of the quantum of vibrational energy and the size of the molecular frequency of vibration, what proportion of the total inter-molecular distance represented the amplitude? And so I discovered that there was good reason to suspect that the linear restoring force couldn't last that long. I don't know how far I carried these things, but I wrote what is essentially the guts of a theoretical thesis. Then I realized that jim (Brinsmaid) who had undertaken to develop the infra-red spectrometer for a thesis,working with Wallace Sabine, really had a tool ready on which I could go partners with him into the laboratory and see if these extra bands, which it seemed to me ought to be there, really were there. We hunted and found them. The real theory was quite appreciably different from the picture that I was working with, for I was still imagining large-scale vibrations emitting classical electromagnetic waves. I hadn't got any photons in mind at this time. But at any rate, I did work along with (Brinsmaid). We had a very happy collaboration, and that was that. My mind was buzzing with various other things that seemed to come out of this, the problem of rotational distortion, a band as the frequency rotation got larger stretched, and what would this do to the band, and so forth. These things were buzzing in my mind. I got my degree and the war was already on. I had to leave Harvard, actually to go to Buffalo, where I was with Curties Motor Corporation for the rest of the war.
When you say you didn't have photons in mind, and that you were thinking of classical emissions, this means that you were thinking of the fequency being determined by the mechanical frequency of the rotations?
...I know that I was in a very hybrid state of mind. I didn't have all the background about the photo-electric effect and the things that Einstein had been thinking about. I realized that there were energy levels and something about how they were spaced and how this was tied up with the frequency. But I was still thinking of the frequencies as being determined by the frequencies in stationary states, rather than by the energy differences....I'm very puzzled about this now. Of course, whatever I did was, let's say, done in relative isolation. I can't remember having had a chance to talk about these things very much with anybody else who was making quantum theory for himself. And I always had a tendency if I saw something that I could do myself, to drop all reading and go ahead and try to do it for myself, rather than to be sure that I had the full background and knew what everybody else was thinking to work from. And this in a way is a lot of fun — to work that way — but it means that you often do things that are behind the times.
But you think there was probably nobody else here who was really trying to work from the Bohr approach?
No, I don't think so. It was long after this that G.W. Pierce was struggling with the effort to make a classical atom that would do the things that were needed. He was our leader in electronics. We didn't call it electronics then, but high frequency radio oscillations. A very ingenious man indeed. But long after it was time to do such things, he made this excursion out of his area because he was irritated by these strange, paradoxical assumptions that other people were making But with no conception of the number of points at which the new theory fitted into quite different sets of facts, he would pick out one little place which would explain the hydrogen atom alone, ant that wasn't the problem anymore.
I get some impression from what you say, that as of 1915, '16, '17 at Harvard, there were not very many people, perhaps none, who were really more than pretty vaguely aware of the extent of the European background for the Bohr atom.
I think you're right.... I began to be interested in something we called quantum theory and h at that point — that is about 1915. When the war was over and I came back here in 1920, it then immediately developed upon me to give the instruction in quantum theory that was given. Theoretical work in this area was simply not available anywhere at that time. Of course everybody had dropped their scientific work for a couple of years there — as they did later during the second world war.
It was pretty clear by 1920 though that the field was on the map here, I take it.
Oh, yes. It would be interesting to get somebody to chase the records down and find out in what year the first course labelled quantum theory was given, at Chicago at Princeton, at Yale... There must be a record of colloquia subjects in the University Gazette.... Well, I could learn a great deal of the history of physics by reading the Gazette.... It's very difficult for me to disentangle in my mind sessions of colloquia when I was still a student from sessions of colloquia when I became an instructor. I have very definite pictures of some of these colloquia, but they could easily have been in the instructorial days. Everything was so uncomplicated in those days. It was simple, there was such a small number of graduate students and a small staff. We didn't hold our colloquia in the big lecture room at that time. And one understood all the papers, or at least one understood them unless the fellow who gave the paper didn't do a very good job. And I have a feeling that as time has gone on and as physics has gotten more specialized, that the control of any one person over understanding what goes on, even in his own colloquim, has tended to decline, and that there is an unfortunate tendency even among experts to say nothing lest you reveal your ignorance. I was out at Ann Arbor, I think it was the summer of 1928. Kramers was there. I remember there that Kramers did what A.G. Webster did at meetings of the American Physical Society. He insisted on understanding everything that went on, and when the speaker said something and Kramers couldn't immediately understand, he held him up, until it was straight. And this was very good training for everybody in sight. In the same way at our colloquim, W.S. Franklin used to come and insist on understanding all the things that were really beyond him.Certainly the sense of bewiderment that is common nowadays was not so common then.
Shortly after you got back from Buffalo, you got involved with the helium problem?
Yes.... I guess only one paper. And that paper in a way was totally silly. It led to a model which in the way of the Bohr theory gave an answer that wasn't too far out of line and looked plausible and all that. But I was young and had this tendency to take the bit in my teeth. I never talked to Saunders, who had come into the department at the end of the war, about the spectrum of helium. And I changed the accepted interpretation of the normal state. I said, this must be — well, I don't know whether it was ls or something else. If I had talked to Saunders, he would have showed me that my spectroscopic identification was something absolutely not to be tolerated. He told me about it afterwards much to my chagrin, but it didn't upset the world of physics very much. I did this same thing, in my rawness, in connection with the band spectra. Coblentz down at the Bureau of Standards, also a Case man, had studied infra-red spectra, and made charts about a number of the absorbtion spectra in infra-red. These things fitted with my ideas to a certain extent, but then there were quite a number of things there that I couldn't take care of, that didn't fit in. I suggested that there were some impurities present. Oh, I got a very hot reply on allowing that kind of a suggestion to appear in a paper, live and learn.
Did you have any sense that the helium problem is really bothering people? When you went at that, when you attacked this one, did you have any sense of its being a key problem?
No. I was hunting around for places in which the kind of ideas I had would work. Of course anything that went beyond hydrogen and could get anywhere was obviously a very important step forward. And I'm sure I didn't underestimate the importance of the problem. But I had no notion of how we were going to get away from the classical mechanics being the mechanics of the particles in the stationary states.... The integral pdq equals nh was the kind of thing I was working at. Actually I spent much too much time trying to refine the application of these ideas to molecules. And when the new quantum mechanics was coming along — actually I was in Germany in 1927 — the matrix theory was already on the boards,and schoedinger's theory was on the boards, and I was still working with a problem on rotational distortion. It wasn't coming out right, and yet there were enough parameters in the theory so that I could not but believe that it was a failure on my part to get the correct combination of parameters. I wasted a lot of time when I should have been studying wae mechanics in fixing out a paper on what now appears to be triviality.
How was your German in this period? Or did you keep up with the German literature?
Well, to a degree.
And how about the role of Atombau by Sommerfeld?
Well, as soon as it was out I was using it, and I used the 1st edition, and the 2nd, and the 3rd, and the 4th editions in turn. I got used to scientific German as a graduate student. Osgood's Lehrbuch der Funktionen Theorie was the place in which I studied complex variables way back in 1913. I never had but one college course in German and one year of high school German, but I expected to read it, and I don't think the language barrier was very serious.
Were there other people here after the war with whom you talked quantum mechanics?
Well, I began to have students immediately. Of course Van Vleck appeared and was my first Ph.D. In those years — this is before the new quantum mechanics came out — I was talking with him, and as I started immediately to teach a course, there was constant conversation between me and the class about these things. When Sommerfeld's phase integrals appeared on the scene, I remember I gave a colloquim talk on the subject and was afterwards told by a colleague that I didn't succeed in getting it across.... That would be after the war, but early after the war.
Was there anybody here who knew about the Hamilton-Jacobi techniques? I remember there's just a little bit of it in Osgood's Analytic Mechanics.
Yes, well we had the basis for this sort of thing — the Hamilton principle and so on. All this was tied into calculus of variations. I got a thorough grounding in calculus of variations under Osgood, way back there at the beginning. But angle and action variables, no. I never heard of those until — well, I suppose this came mostly from Kramers' exposition... I have his book here somewhere.... Let's see. 1919.
That's immediately after the war, I'd forgotten. That was the place to learn action and angle variables.
That's where I learned them, at any rate.... The work that I did with the committee on Molecular Spectra of the National Research Council was the center of my thought for a couple of years. And that had these angle, action variable ideas in it. And it meant a great deal to me to get appointed as chairman of that committee, and I was really only a youngster. But it was the old story. Lee Page was the theoretical physicist at Yale,and he was a purely classical person. And you could go the rounds. Theoretical physics was just trying to get its foot in the door. The foot really came in the door properly with quantum theory. Otherwise, there had to be somebody to teach the advanced courses in kinetic theory and gases and so forth. Usually the experimental people weren't quite up to these more advanced classical textbooks, so somebody would teach courses like that.... Somebody in the physics department would simply undertake to work that out. And this was the nearest thing to a theoretical physicist. That person might not have had much time for exoerimental work. The way I picture the thing, and I may not do justice to what was going on in the other places, was simply that every place there was somebody who knew mathematical physics,we'll say,but was not doing anything striking in the way of creative work in it....
I'm curious, Ted, about the Duane grating theory. I'm not sure whether he was here when he did that. I wonder whether it got talked about here, even.
Yes, I think this probably was done when he was here. I have a full record in my mind. Duane was an important and highly modern influence in the department from the time when he came here, which I suppose was at the end of the war. And these experiments ha did with Hunt on the limit of the X-ray spectra look to me still like terrifically important experiments. And then this theory of momentum, I don't even remember (that it's the grating theory that you were talking about).... There was a good deal of interest. I myself was among the— had an instinct of incredulity about the work and probably never was as excited about it as I should have been. I didn't think that was the way.
Was Duane mostly an experimentalist really? With an ingenious mind for this sort of thing?
Yes, that's right. That's right. He had a battery that he'd built up in the top floor of Jefferson, where the present undergraduate library is. It was a 100,000 or 200,000 volt battery made of test tubes. He built it himself to get a steady source of high potential for his X-ray work. Then later he moved into this building. Down in the basement there he had some rectifier schemer, I think, for taking out the ripples in rectified current to get the potentials. But that battery remained the source of anxiety to everyone around, because it was so dangerous. They had incipient fires once or twice.
Was it your feeling that the Duane grating theory was really an attempt to stay away from photons? It was an ingenious piece of conservatism.
No, I don't think that I thought of it as a piece of conservatism.... At this moment I've gotten kind of unclear in my mind as to how it went. But it just seemed to me that it's the kind of theory that's meeting a special situation in a particular spot. It didn't make sense that it could be generalized to make a whole new theory. When you come to things like the matrix mechanics and the wave mechanics, here was really a new, generalized language, and I didn't have that suspicious feeling toward that. No, I remember that I was quite unbelieving the first time I saw De Broglie's paper on the wave properties of the electron.
Do you have any notion when you saw that?
I don't even know what the interval of time was between De Broglie and Schroedinger.... I probably didn't hear about it until after the thesis was out.But I have no very clear recollection except that I'm quite clear that I was too conservative to see the possibilities in that first work of De Broglie's.
Do you, Ted, have any recollections of the reception here, or Duane's reception in particular, of the Compton effect?
No. I suppose that this is the kind of thing that one would recieve with excitement and "if it's true" question in the back of their head. It certainly was a jolt that here was a case where the frequency was changed in transit.
Duane denied it. There was a considerable battle for a bit.
Well, this is quite plausible to me, but I don't remember having so to speak gotten personally involved in the business. It didn't take me very long to get adjusted to it.
Could you describe the situation with Webster. That is, this whole question of what happens to a profession, when the field changes under it.
Well, what happened in Webster's case I think is exaggerated, so to speak,by his special position. He wasn't just an ordinary physicist, but he was the head of the works of the department of physics at Clark university. His books on mechanics and so on were the last work in American scholarship in this direction. And among all the people in American Physics, there was nobody whose judgment about what's possible and what isn't possible would stand higher than he is. As I remarked before we had our recorder started, he used to dominate the meetings of the Physical Society, considering himself to be competent to be the critic of anything that came along. He had a great big booming voice which added to the impressive effects of remarks that were offered. Devastating — and nobody to stand up against him.
Was it entirely his personality that nobody could stand up against him, or was a good deal of it his own learning?
I think his learning. He had the learning. He had a good mind, and he had a way of expressing himself that just carried things before him in meetings of the Physical Society. I don't know how many meetings I actually attended, but I have been present to see this thing. I was present one time when Arthur Compton tried to sneak in a paper at a meeting of the Physical Society as "Comment" on somebody else's paper because he wanted to get out of town, and he tried to put his paper in at an earlier point of the program. It was relevant and he began to comment, and slides were produced. And Webster stepped on him. It was a very hard step, and Compton retired in red confusion. But this was a kind of thing that nobody else would have undertaken to do, but Webster did. I went to see Webster at Clark when I first came to Harvard because this Fourier series work that I'd been doing with Miller. I wanted some kind of advice about how to proceed. But he just couldn't keep up with what was going on when the quantum theory began. I always understood that the reason that he killed himself was simply because he discovered that suddenly physics had gone off in a new direction and he was unable to follow, and he couldn't bear to take a seat in the back row and be silent. I know plenty of other people who know more about that than I do.... We had his funeral in Appleton Chapel in those days. I think it was mainly Harvard graduates, but I remember the funeral.
I get from what you tell me a general sense of great experimantal ingenuity — this is now to sort of classify and try to characterize the American scene — of areas in which really first-class individual experimantation was going on. But very real backwardness in theoretical terms.
Yes, oh yes. Most certainly.... I think the amount of mathematical training expected of students was very much less than came to be later on. I remember one time being present at a doctor's examination at the University of Chicago. I had a summer — I'm not quite sure of the summer, it was adjacent to the summer I was out and heard Kramers at Michigan — I was out at Chicago teaching in the summer school. And they invited me to be present at a doctor's examination. This was a general examination covering everything in sight including mathematics. And they asked me if I wanted to ask any questions, and I wanted to ask the candidate about differentiating the definite integrals with respect to the limits of integration. And he was in hot water. The procedure there at that time was that when a student began to do graduate work, they began immediately with the thesis. So they started experimental work right away. Here we were more conservative, and nobody began his thesis work until he'd been here at least a year, more likely two years. I think that there was a good deal more mathematics available at a higher standard of mathematical understanding. But I can remember being questioned about Hamilton principle in my doctor's exmination in physics.
And that would have been a general exam?
I think we didn't divide the subject of physics up into as many little compartments for prelimenary examination at the time that I was being examined as later.It seems to me that the whole department was present in that. And then as the department grew and the specialization increased, why we specialized in those examinations.
It seems you yourself had had a relatively large amount of mathematics.
Yes. This I had because I already had a mathematical interest from back in Case days. My whole desire was to go into theoretica physics. I didn't have any thought of doing experimental physics. And again, as I remember it, the department agreed that I might be allowed to do theoretical physics for my thesis. But when the time came, there was a change to collaborate with (Brinsmaid). This looked like the thing to do. Van, in the end, became the first person to do a purely theoretical physics. Mine became, in the end,a mixed thesis....With regard to my doing a purely theoretical thesis, if there was resistance, I didn't hear about it because I was a student. And I think Bridgman was carrying the ball for me. It had been a definite rule. I remember Lyman saying over and over and over again, "Physics is an experimantal subject." He regarded theoretical physics as an appendage to experimental physics, really, but he wasn't narrow- minded about it. What I do know, what I'm pretty sure of — That's thebes way to put it — is that when I showed up here in the fall of 1913 as a beginning graduate student, Lyman was then the chairman of the department. And he was in the middle of ultra-violet researches. I suppose his main interest was in pushing the limits of what you could reach. There was the Schumann region; the Lyman region was beyond the Schumann region. You should see, at leastglance over, Lyman's book on the spectroscopy of the extreme ultra-violet.... Saunders washere as a spectroscopist also, working in the visible and near ultra-violet. I would have supposed that studying hydrogen in the far ultra-violet; would have been the first thing one would have done. [ After Bohr] when one had the tools. Whether this is actually what hanppened or not, I don't know. Maybe he studied zinc instead....
You just go on the way you were, and I will try to fill in the pieces.
I will mention that this reviews a lot of physics articles which I wrote It gave me my first start in trying to say something in a more general way and to try to organize facts and so on.somewhere along that time, when Ehrenfest was on a visit here, he made the remark to me that the greatest physics is the most general physics. If you wanted to really accomplish something, you did it on the general plane. And I then, after writing this, had the ambition to do something that was more thorough and complete. I wasn't satisfied, I wasn't happy, and I had to get this desire to do a real job with it out of my system. Well it took me about seven years to do this. Partly because I was slow. And there were many problems which I had to think through on the way. It was a very short time after this book was published that the war came on, and I then became chairman of a wartime educational institution, with no time for science. I did do some work on propeller research. By the way, I don't think any of my reports on propeller research ever got into the bibliography. They were published outside, secret archives. And when the war was over, I was 56 years old and had been away from the current of events, partly by my absorbtion in writing that book. Also administrative work had made a big gap. And physics was moving very fast. I saw myself spending the rest of my life panting to try to keep within hailing distance of what was going on.
I have a second part of my personality which is interested in education and people and comes out in my ministrial father. So the general education business that came along gave me a chance to turn into a new direction and to do something which I thought probably nobody else would be able to do because nobody else was interested and far enough along in his academic career so he didn't need to think of the effects of general education activity on his career. And I deliberately quit being a scientist at that point although I continue to teach.
About the same point that I quit being a scientist.
The little bibliography — the parts that go beyond this indicate at any rate the directions of my thoughts, which were not 100 per cent on general education. I did get involved in writing that critical report on the teaching of electricity and magnetism which you probably have seen. And this cost me many, many hours and weeks, months of time, because we worked on this in summer for several different years. And my whole summer would be taken up. Dave Webster came to see me up in Vermont while we worked on this thing. But there were differences of opinion and points of view within the committee, and in the end the work was done by brown and Webster and myself. This was a costly thing, as far as my career is concerned.
*The following is extracted from a letter from Kemble to T.S. Kuhn of 14 May 1962.*
"I have just looked up my first papers on the infra-red bands and am relieved to discover the reason for the apparent confusion of thought about molecular frequencies in stationary states and radiation frequencies. There is no reference to Bohr in the three papers published before I went to Buffalo and it is quite clear that I was unfamiliar with his work. Presumably I must have heard of the photon hypothesis and found myself unready to accept it. At any rate the references are to Niels Bjerrum, to the first form of Planck's theory, to Eva v. Bahr, and W. Burmeister. Because I was dealing with the vibration-rotational motion of diatomic molecules the identification of molecular and wave freauencies which I made was not so obviously impossible as if I had been working on the hydrogen spectrum. It did get me into trouble, however, and I had to correct the trouble in my first post-war paper, published in February, 1920, The Bohr Theory and the Approximate Harmonics, etc. It would be interesting to look up the date at which Bohr's first paper was first reviewed at the Harvard physics colloquium and by whom."