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Oral History Transcript — Dr. James Arnold

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Interview with Dr. James Arnold
By Spencer Weart
In La Jolla, California, University of California, San Diego
June 23, 1996

 
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James Arnold; June 23, 1996

ABSTRACT: Beginning work on carbon-14 dating with Willard Libby at the University of Chicago (1946, 1948-1950); work with Hans Suess; Willard Libby's background; work at Princeton University (1955-1958); research on Beryllium isotopes; work with Ernest Anderson on carbon-14 and discussion of the chronology and events that surrounded the publication of his paper: Arnold, James R. and Ernest C. Anderson (1957); "The Distribution of Carbon-14 in Nature." Tessus 9: 28-32; meeting Roger Revelle, 1956; funding sources for his work; response to his papers within the scientific community; differences between science today and the 1950s.

Transcript

Weart:

This is Spencer Weart. Itís June 23. Weíre in La Jolla, California, and would you say your name please?

Arnold:

This is Dr. James Arnold, at the University of California, San Diego.

Weart:

Well, my main concern is really the one paper that you did with Anderson. Iím working on a history of global warming, and in particularly the big change that took place in the late 1950s when people began to realize that the oceans wouldnít take it all up, and all that whole range of things. But as background to that, I want to say something that youíve probably said in this other oral history that youíve been working on, but Iíd like you to go back and say how you got — just give me a little of the background of how you got involved with radiocarbon and Libbyís group in the first place.

Arnold:

Yes, I had come to Chicago in early 1946 with a new Ph.D. in secret research.

Weart:

The Manhattan Project?

Arnold:

The Manhattan Project. And Libby had recruited me immediately. I was one of the first post-docs to arrive, and I was willingly recruited, because I wanted to learn about radioactivity. My part in the Manhattan Project had not dealt with that, and he initiated me into a number of things. Then I went to Harvard for a year, and, at the end of that time Libby had funding for carbon dating, and he called me up and offered me the job. I think one of the reasons for that was that my father was a very serious amateur in Egyptian archeology. He was American Secretary of the Exploration Society of London, which meant basically he was a fund-raiser for them, but I grew up with a library full of books on the subject and all that. And so I spoke the language, and I could appreciate immediately what an exciting project this was.

Weart:

Libby was already interested in the Egyptian mummies and so forth.

Arnold:

Yes. Well, particularly as a calibration. Right.

Weart:

Which it was obvious that was how far back you could go.

Arnold:

That was to demonstrate, yes.

Weart:

I see. So, about the group there, did you interact also with Libby? Iím sorry, with Urey?

Arnold:

Oh, yes. The Institute for Nuclear Studies, the Fermi Institute now, was an extraordinarily lively place. It was one of three institutes. Fermi was the famous leader, but, so they say, exaggerate slightly, Nobel laureates or future Nobel laureates were kind of a dime a dozen around that place. And Leo Szilard, who we were talking of, was in another institute devoted to biology. So there were stellar people around, and people communicated with each other. There was a lot going on, and it was exciting, and people talkedÖ

Weart:

You were there as a student and apprentice, but did you have anything to do with funding, with where the money came from?

Arnold:

No. The funding had been provided by what was called the Viking Fund, now the Wenner Gren Foundation, before I arrived. It was what enabled him to bring me there.

Weart:

Right, because of the interest in archeology primarily?

Arnold:

Wenner Gren Foundation is devoted to archeology as far as I know. It was certainly then, and they had apparently the notion of using physical methods in archeology.

Weart:

I was just wondering, you had an interest in Egyptian archeology. Your father had an interest inÖdid you have interactions with funding people?

Arnold:

No.

Weart:

Is that so? Thatís interesting, so itís just all [???]

Arnold:

Iíd met Paul Fejos I think, once. We gave a little, what shall I say, eveningís discussion once at their headquarters in New York. I changed the slides while Libby talked.

Weart:

Was there any thought as to what else this would be useful for? Ultimately, of course, it became useful for things like geophysics. Was there any idea of that at the time?

Arnold:

My sense of the — well, at least in the following narrow sense, I think, very limited. In the following narrow sense, there was, that we all agreed that if Carbon-14 dating failed, if the assumptions were wrong, we would be learning something about the world. Or if it worked we would be learning something about the world. As it happened, it was somewhere in between, as we look at it back today. The assumptions did not work perfectly, and that was what made Carbon-14 geophysics. But I think the development of that side of it owes at least as much to Han Suess as it does to Bill Libby or any of the others.

Weart:

Did you have relationships with Suess, is one of the things I was going to ask you about, at Chicago? Did you know him?

Arnold:

Yes, yes. He worked in the next lab from me. Harrison Brown brought him over, and we got to know each other.

Weart:

Oh, I didnít realize that.

Arnold:

Oh, yes. Harrison Brown was the one who brought him to the United States.

Weart:

Oh, I didnít know that.

Arnold:

Harrison isÖhe had some of the most underrated people. It was interesting how he had rather prominent public career, but Iím not the only person who thinks heís been amazingly forgotten since he died.

Weart:

Well, Iím aware of the book that he was doing about that time about the future, and I also know, of course, that he hired Keeling who got involved in Carbon-14 work, so he must have had broad interests in those [???].

Arnold:

Yes, Keeling was his student.

Weart:

And, letís see, Craig, no Craig didnít work with them. That was Keeling. You know Harmon Craig, also, I suppose.

Arnold:

Yes, of course, he was a student of Ureyís.

Weart:

So, then you were involved largely in the instrumentation side?

Arnold:

Yes, I was in the instrumentation side, the chemical preparation. Ernie and I were the people who did the day-to-day work in the lab, and, of course, we talked about these things, and talked about them with Libby. But I find myself perhaps over-emphasizing, but itís hard to over-emphasize, how much this was Libbyís project, and how little we contributed besides useful pairs of hands and conversation. We were apprentices. He was the master.

Weart:

I have another question about instrumentation thatís been in the back of my mind. There were other people at the time who were very much concerned with detecting very small amounts of radioactive materials, and those were the people who were trying to figure out how to detect Russian bomb tests and so forth.

Arnold:

Yes.

Weart:

Did you have interaction with those people?

Arnold:

Tony Turkevich, who was also a professor there, and a personal friend, was engaged in that activity. And, in fact, he and I shared an apartment at the top of the Libby house if it sounds like a small family. And Iím perfectly certain that he must have used some of the notions that he picked up on our side besides being an absolutely first-class scientist himself, and plenty good enough to think of his own methods. So in that sense, yes, but I was not cleared...

Weart:

What about going the other way? Do you think that you learned stuff from them that was helpful in any way?

Arnold:

Not very much. I wasnít cleared. Libby may have, but the fact is imperceptible to me. The major inventions, the Screen-wall Counter he invented before World War II, the Anti-Coincidence thing was in the air and known, and I donít remember any, you know, sort of amazing innovations that popped up suddenly without explanation. For one thing, those people had a lot more money to spend than we did, and that may have limited the transfer in the other direction. But itís certainly possible there wasnít that much at that time.

Weart:

You mean [???] [???]. Didnít the Air Force give some support to your group also?

Arnold:

To my group? Much later.

Weart:

It was later.

Arnold:

I had an Air Force grant, but that was in the perfectly normal course, you know. One applied, one wrote a proposal. And what their motives were — Libby, too. Libby, too, for me. In the early, say, 1954, when the tritium work was done. That was supported by the Air Force. So yeah.

Weart:

Iím sort of curious as to how it came about that Libby became such a big man with the AEC and so on.

Arnold:

Well, that goes, of course, back to his war time years.

Weart:

I see, and just sort of continued.

Arnold:

He had been veryÖIíve commented on it many timesÖhe was an assistant professor before the war. When he went to Chicago he was one of the galaxy of stars, and he was treated as such. The difference was the Manhattan Project and his work under Harold Urey at Columbia.

Weart:

So now you leave Chicago about the same time Craig and Suess, Iím not sure, but they went to Scripps. Were you ever considering going to Scripps also, at the same time?

Arnold:

I donít know how much time to spend on this story.

Weart:

Well, tell me the story. Actually, Iíve seen a few letters, so I know itís not a totally new question.

Arnold:

OK. OK. I was looking for a job. Suess, Craig, Wasserberg, who am I leaving — oh, James [???], were also looking for jobs at the same time. And I had the notion that it might be possible to go as a collective rather than as individuals here, and was peddling that notion as best I could, and all these people...

Weart:

I didnít know it was your notion. I just knew that there were notions in the air.

Arnold:

Well, thatís correct. I came closest to selling it in Pittsburgh to the Melon Interests as the source. There was also some slight interest at Stanford, though that didnít ever really blossom. And when this broke up, and the impetus was that, again, Harrison Brown at Caltech decided he wanted Jerry Wasserberg, which was a pretty cool move, and that was obviously too good an offer to possibly refuse. And Roger Revelle heard about this, and said he had money for two people, and he decided on Craig and Suess, and I went to ChicagoÖto Princeton, and Chazeray [?], to the puzzlement of all of us, went to the University of Miami.

Weart:

And everybody did very well.

Arnold:

And everybody did very well.

Weart:

I see. I see. OK. Now, skipping over some of the stuff you did to get on to the Carbon-14 in the ocean story, or, to me, itís the Carbon-14 in the atmosphere story. To begin with, did you have any interest in the oceans at all before this, or in the atmosphere before this, or what were sort of the antecedents?

Arnold:

Well, thatís a little hard to say. I had an interest in the world.

Weart:

Right. But specifically?

Arnold:

I think my consciousness of the earth as a system, of the Earthís surface, ocean, atmosphere, land, as a system, was developing in this period. I was already very much interested, as I started my own research, in discovering some of the isotopes that Libby had left for the rest of the world, and particularly the Beryllium isotopes, Beryllium-7, and Beryllium-10. And Beryllium-7, 53-day half-life atmospheric tracer, and so I began to think about that. And I think it was in that way, though certainly it must also have been true that the first glimmerings of deviations which Han Suess again, and Devries [?] in Holland, developed from the assumptions whetted my interest in the use of this as a tracer for those phenomena. I think thatís probably the sequence, although Iíve always kind of prided myself in being broad rather than narrow, so I, you know — this was something to look at and look at.

Weart:

Do you remember at all when you first heard about the possibility of global warming, Calendar and all that?

Arnold:

No, I canít. I saw recently a quote from Svante Arrhenius, who seems to have come on the notion of global warming about eighty years before it was on the air.

Weart:

Oh, yeah, it was on the air for a long time. Most people donít seem to remember when they first heard about it. They seem to have sort of absorbed it.

Arnold:

I think I can be added to your list. Itís interesting — Weíre coming, I suppose to the Tellus Papers [?], and [???] and Anderson as well as Revelle and Suess. And Hans, as he liked to point out, had talked about this sort of thing in a couple of earlier papers. But when Anderson and I probably were driven as much as anything else by the interest in understanding the deviations of Carbon-14 from the ideal curve, and, if one did understand that, then one could improve Carbon dating. That was certainly, I wouldnít say by any means the exclusive motive, but I think certainly speaking for myself, it was one of the motives.

Weart:

It is much like what you said earlier: that it works both ways. You understand the Carbon in order to understand the world, and vice versa.

Arnold:

Well, we had long later experienced when we were doing our work on the Carbon-14, all the radio-isotopes, and extraterrestrial materials, the notion of the screw making a half turn on the screw. You learn more about the history of the target. You learn more about the history of the cosmic rays. Then, when you knew more about the history of the cosmic rays, you went back to the history of the target with approved tools. And this was, I would say, this one didnít have perhaps only one or two turns, but it was a prototype for that.

Weart:

Right. And then, Suessí results were very preliminary and they were rather puzzling to people. It didnít fit together too well. That wasnít because of Carbon-14 from bomb tests, was it? It was just because they didnít very techniques yet?

Arnold:

Well, actually, certainly the techniques were improving, and Suess was one of the people improving —

Weart:

Weíre talking about his papers, you know, like 1955 —

Arnold:

Yes, yes, I understand.

Weart:

Which later turned out not to be fairly far off the mark. And why was that?

Arnold:

Hans was always famous for getting the right answer from very limited data, and he showed it at that time, and he showed it many other times. But yes. I think that there were limitations. I thought many times, and said many times, that it was an advantage to us when we were developing, to Libby, when the work was originally done, that the errors were large. Because the errors were large, the first publication said ďitís following the exponential.Ē And the archeological people, with some exceptions, just jumped at it, and believed it. And then by the time that these other things began to force themselves on peopleís attention, it was already established, and so they could be treated as deviations, and used, and dealt with. Whereas, if we had had the, say, when Suess eventually published this curve with all the Suess wiggles in it, if that had been the first thing, I think there would have been great confusion and skepticism and arguments.

Weart:

That was much later, of course.

Arnold:

That was much later. Oh yes.

Weart:

What do you think were the main impediments in the mid-50ís to getting good figures? Was it the world, was it the changes in the sun, or was it just bad instrumentation? Was is bad signal preparation?

Arnold:

Well, the bomb things didnít help, but actually samples — you can make measurements, as Suess did, of sea water. You can make measurements of older terrestrial samples, which didnít show bomb effects. Curiously, the Suess effect, the combustion of dead Carbon, was a very powerful tool itself, as the bombs were, to unravel the [???]. So both these difficulties turned themselves to a count [?]. And when people began to think about it seriously, those facts came — I mean it took no great insight to see that.

Weart:

OK. Getting back now to the Tellus Papers. Iím not sure where to begin. Letís begin with Anderson; where does he come in? He was in Chicago also?

Arnold:

He was in Chicago. He had gone — he had his name on all those papers and he was a critical person there. He went to Los Alamos and remained there.

Weart:

What was he doing at Los Alamos?

Arnold:

He was in the Health Division. He was helping them with his sensitive counting techniques to do all sorts of things, and his other laboratory skills. Heís an absolutely first rate laboratory scientist. And he and I remained close. We became very good friends on the project, and are to this day. And I guess Iím not distorting the record when I say that I kind of made it my business to seek out collaboration with him, because our talents seemed to complement each other very nicely, and we were good friends, and enjoyed each otherís company. So I believe, as far as I remember that paper, that it was originated by a discussion somehow, on the phone, or letters, which led me to say, ďhey, Ernie, why donít we do a paper together on this.Ē

Weart:

Long distance was rather rare, especially at the time.

Arnold:

Yes, it was rather rare at the time.

Weart:

You didnít get together?

Arnold:

We did. The exact history of it, I donít know that well. Iíd have to go back to the lab notebooks and so on. But maybe somethingís in my papers. I doubt it. And Iím vague, but what I do remember was working hard on it. I spent the summer of 1955 at the University of Mexico in Mexico City, the National University of Mexico.

Weart:

Oh, I didnít know that at all.

Arnold:

And it was a great time, because I couldnít do any laboratory work. I was moving. That was the summer between the last at Chicago the first of Princeton, and not much distraction except the exciting city. And so I did a lot of work, and I probably was corresponding with Ernie at that time. The manuscript, first, you know, reasonably full manuscript, if memory serves, was completed by the winter of Ď56-í57. I came out here. My first visit to La Jolla was somewhat after that, shortly after that, perhaps the spring of Ď57. Donít trust my chronology.

Weart:

It was spring of Ď56. So you came and visited here.

Arnold:

And then I came and visited here, and by that time the notion of my coming here was already a little in the air, and Revelle and Suess and I exchanged manuscripts.

Weart:

Now you must have known before that that they were working on something similar, and [???] [???] [???].

Arnold:

Yes, I did. Hans, again, was a good friend. I didnít know Roger. I met him on that — no, Iím not sure.

Weart:

So the idea for this paper with Anderson must have sort of been in the air.

Arnold:

Yes, because the deviations were beginning to call for explanation, and also Roger, I would guess, must have picked up on the possibilities which Hans, of course, already had in mind, but Roger always had a little more energy and focus, and so they were doing that. And I had probably corresponded with Hans about some of the questions that were raised, and he told me they were working on something similar, so we had already agreed to exchange manuscripts. Iíll tell one story if we have time for it. Roger came late to my seminar. I was giving a seminar on Beryllium-7 in the atmosphere.

Weart:

Here, at Scripps.

Arnold:

At my meeting with Roger, and I was talking away, and Hunt — he sat down in the front row. Herman Craig next to him handed him a copy of my manuscript. At the end of the seminar, he asked, as I recall, the best questions that anybody asked about what my seminar, and then, of course, I came down. We were introduced. On the way out he said to me, ďThere are two serious mistakes in your manuscript.Ē I said, ďHuh?!Ē He had misinterpreted one of them, but the other was a real mistake. I said to myself, this guy is the equivalent of the president of the university? This is a fast gun, you know. So we started off on a very, very good note.

Weart:

OK, so then you exchanged the manuscripts, and then, at some point you agreed that you would publish simultaneously.

Arnold:

Yes, I think this had been agreed before. Iím not sure of the chronology, but it was a fairly obvious thing. There was lots of overlap between the papers. It was obvious at the same time — we had been working independently — the sensible thing to do was to do that.

Weart:

Now, Iím curious about the chronology here, and I donít know whether you can help me or not. This exchange and so forth, and your paper seems to have been ready about in the spring. And then, as near as I can tell, Revelle didnít do anything and sat on it. I had a feeling that this was the period when he was coming up with whatís now known as the Revelle Effect or whatever, and just sat on it. And then there was a letter from you sort of in August or July or whatever, saying whatís happening. And then very shortly after that, the letters got rushed into publication, sort of patched in the Revelle Effect in his papers. Do you remember anything about all that?

Arnold:

Not very much. What I do remember, of course this is the third paper by Craig.

Weart:

Yes, that was part of the whole thing.

Arnold:

And one of the curiosities to me when I arrived at Scripps was to discover that before a paper went out of the Scripps Institution of Oceanography it was internally reviewed. OK. And Roger had decided that Harmon must be the appropriate reviewer for their paper, and so, inevitably, he reviewed our paper as well. And he then wrote a paper of his own. And so that was the delay that I was most aware of, but if there was some lack of push at this end — you know, I was still on the academic treadmill very much, and I was anxious to get publications out.

Weart:

And Craig, too, no doubt.

Arnold:

Yes, and Craig too, no doubt.

Weart:

OK. Then, getting back again to the question of support for this. You were, what? You were probably on ONR contract at the time?

Arnold:

No, I was not on ONR contract. The first grant I ever had was from something called the Office of Ordnance Research, which is a very small Army outfit.

Weart:

Thatís Army. Where did they come in?

Arnold:

They supported me, my first efforts in Chicago, which ended up in the development of the liquid simulation counter.

Weart:

And why did the Office of Ordnance Research take an interest in this?

Arnold:

Youíd have to ask them.

Weart:

Libby got it for you. You didnít go to them. Libby got it for you.

Arnold:

No, no, I went to them. I wrote a proposal. They were a government source of funds like ONR, NSF, AEC, any of these other groups. They were small. They were starting up. It was easier for an assistant professor to break in. Somebody advised me that that was a good thing to do, and I went and did it.

Weart:

I think they supported Von Nymen [?], didnít they? I canít recall.

Arnold:

They might have. But they were a very small outfit. They were a pleasure to deal with. There was a man named Sherwood Givens [?]. I would call him up and get an immediately reply. They were on something like a three or four million dollar budget. They were just, to me, they were very, very good. Then the Air Force — I canít produce the chronology of grants. I got an NSF at some point, and, you know, as things built up, and when space started, that was a whole different world. But back then it was a matter of — you know, the numbers are much smaller. If you had a twenty-five thousand dollar grant for a year, you could support a technician, a post-doc, da da da da.

Weart:

Right, right, right.

Arnold:

So these things went pretty far. I remember the first one. The second or third Iím not so clear about.

Weart:

Do you have any idea what the Army, or, as it might be, the Air Force would ever expect to get out of it?

Arnold:

Well, I thought up that the Air Force might indeed have some reason to be interested in an atmospheric tracer, in the circulation of the atmosphere. Obviously, thatís their medium. As for the others, those were the days when it was really considered a great thing to push science in the United States. We were going to become, and we did become, the leading world power in science, and that was a broad objective of the government. What the specific things were, I doubt I cared much at the time. I mean, I had some, shall we say, ethical concerns about doing certain things and not doing other things, but if I wrote an open proposal, and the Department of Defense chose to support it, and didnít make me get a Q clearance and work with them and whatever, that was fine with me.

Weart:

So this was in fact, I guess, your main source of support then were these military agencies which donít really exist now in that sense.

Arnold:

Yes, thatís correct. Thatís correct. The NSF was starting up in the same period. They could command the top echelons, and it took me a while I think to get enough reputation to — and then awhile for the budget to grow. A combination of those things meant that NSF grants probably only came along in the later part of the Ď50s.

Weart:

Now, getting back to the Tellus Papers, do you remember anything about the response to those? Did you get any feed-back that you can remember? You must have gone around giving talks on it, and so on?

Arnold:

I gave a few talks. I smile, and let me — I hope the record will show the smile. What was the curiosity was that almost nobody paid any attention to our paper. Craig got all the attention. Revelle and Suess less so. The only person —

Weart:

Why Craig rather than Revelle and Suess?

Arnold:

Well, I donít know, but at any rate, that was the case.

Weart:

More boxes in his model?

Arnold:

I donít know. I just state the fact. Perhaps more precision in the way that he said things. The one person who ever publically really referred to our paper was Linus Pauling when he was talking about fallout and the distribution of isotopes. He used our paper, which had made mention of the bomb C-14, and somebody heard the results, and he knew me. So heís the only one I remember who really made particular use of ours. Of course, we all influenced each other. I mean, it isnít as if — in the end when all these papers went in, they had a great deal in common, so it didnít really matter terribly much. Certainly Revelle and Suess — and Craig, but particularly, I think, Revelle and Suess, did more on the environmental consequences. They thought more about that. We mentioned it. Craig discussed it, but I think the Revelle and Suess paper today is seen correctly as the most important of the three papers where global warming and other broad issues are concerned.

Weart:

Although it didnít seem to attract much attention at the time as far as I can tell. What we now think of as the Revelle Effect was really recognized in there for a few years.

Arnold:

Yes.

Weart:

And I havenít noticed anybody really referring to it for several years.

Arnold:

I think thatís quite right. I think that none of these papers had an enormous influence at the time. They were published in an unusual journal to begin with; that might have added to that slightly.

Weart:

Tellus was not very widely read at the time?

Arnold:

I donít think — of course it was read among atmospheric scientists, but atmospheric scientists were a very, very little profession of the day.

Weart:

Yes, you must have known all of them, I suppose?

Arnold:

Well, I knew a lot of them.

Weart:

Even though you werenít yourself, an atmospheric scientist.

Arnold:

No, I wasnít, but I certainly ran into a Jule Charney, and Bert Boleen, and other big names in the field; Rosby, just because it was such as small group.

Weart:

Well, anything else? Youíve given very good, concise answers so Iíve run through my questions and youíve already answered them. Anything else about all that period that strikes you?

Arnold:

OK. Well, the curious thing to me, I would say the strangest thing to me, in that period, and this came up first in connection with the Beryllium-7 work, but it also applied to this, that the meteorologist — I had gone through the experience with the archaeologists who had been intensely interested in what we were doing. Many of them had never taken a course in Physics in their lives. They had no background in it. They had to learnÖ [end of Tape 1, Side A] [beginning of Tape 1, Side B]

Weart:

...a great deal of motivation to use their techniques.

Arnold:

Great deal of motivation to use their techniques, and I remember vividly one — particularly then going to a meeting of the Society of American Archaeologists four or five years after I had gone to a meeting of the same organization and presented the samples of known age, and there was a symposium with four or five Carbon dating people about the influence. And not only was it just generally recognized that the influence of Carbon dating was very great, but you could see from listening to the general papers that the world had changed. At the first meeting, big arguments about chronology, and so on, and circumstantial evidence of all kinds. Those papers almost disappeared from this other one, not because weíd answered all their questions, but because it was clear that they were answerable, and so why would you want to spend twenty years feuding with your...

Weart:

You could wait for the answers now.

Arnold:

Just wait for the answer. Now when it came to introducing this to the meteorologist, ah, ho-hum. [Voices together — inaudible]

Arnold:

Iím not speaking of, in fact, most of the people Iíve named. Rosby, Boleen, people of that sort were intensely interested.

Weart:

But most of them were bored.

Arnold:

But most of these people — Harry Wexler was the Chief of Research at the Weather Bureau. I had a colleague at Chicago who had written a famous textbook whose name I canít remember at the moment. And I was simply astounded. Iíd go talk to — I just went over to this gentleman, and I had the feeling I was taking up his time. And because — I had to conclude that these people were so focused on the prediction of the weather that anything which did not bear directly on that, the fundamental way the atmosphere behaved, that the stratosphere, and troposphere exchanged, which was Beryllium-7, was good for to a degree, wasnít something they thought about a lot. And that was a puzzle, because, of course, that was a quantitative subject, and so they all had courses in Physics, so I never fully understood that. Of course, the world changed. I mean, now you have the Krutzens [?] and...

Weart:

Sure. Yes. This is very interesting to me, because I have encountered this kind of statement before, and youíre always suspicious that itís the young Turks saying how they revolutionized the field, and the old guys were old fogies, but you were as an outsider.

Arnold:

Yes. Thatís right.

Weart:

And quite a few people have pointed out the somnolent state of meteorology and climatology from 1900 to 1950s or so.

Arnold:

It was a somewhat similar phenomena in geology. It didnít affect us in Carbon-14. Richard Foster Flint was completely with it in every respect.

Weart:

Thatís right. There was a famous difficulty of getting geologists to accept geophysical evidence.

Arnold:

Thatís correct. And the heights had to be captured by the Wasserbergs, and Epsteins, and people like that before it was really met. I think that each science, I theorize, develops a sort of ďinĒ style, a tribal style, and, like Mr. Keelin wroteÖ. Letís say that I see real signs of that, and to this day. We donít have time to talk about it, but we, Lyle and I, and Susumi developed, or were among the developers of a new technique for measuring the rates erosion on surfaces using congenic isotopes. And it went through a much shorter period, by now this is a different world, but a much shorter period in which, again, there was great apathy among the bulk of people in that particular sub-field of geology, which had never had many dating tools, and thatís what we were providing. And we saw it again, but five years and itís over.

Weart:

Yes, one of the things science is going for is it seems to have mechanisms for overcoming those sort of things, which does not occur in many other fields of endeavor.

Arnold:

Thatís true. But I also notice the difference in the world we live in today and the world we lived in back in the Ď50s.

Weart:

How so?

Arnold:

Nothing is as stable. The entrenched groups are not as entrenched. I mean, I donít know in fields far from my own, but I can only say that weíre so, shall we say, inured, habituated to new tools — Well, in fact, back to Carbon-14, something like — it was getting out for twenty years ago. Itís hard to believe accelerometer mass spectrometry came in. And now people can make measurements on a microgram that used to take a hundred grams.

Weart:

And it is accepted it very readily.

Arnold:

Yes. And something like that — of course, itís my trade. I was on the phone to these people the day the paper appeared. But it makes this subject move in entirely new directions, and some — not so much in the dating and geophysics, but in the bio-medical area, the opportunities that are opened up by a technique thatís 105 times more sensitive are huge. Experiments that were science fiction before become doable. And people kind of expect that, and are lying in wait and jump on it. So I think there is that difference, that weíre not as level for as long, and so everybody is better braced.

Weart:

Interesting. Well, I think thatís probably a good place to stop. Let me just ask you one last thing. You might normally have — this is mainly from my own research, but I would normally put it in the archives. Would you have any objections if some other scholar comes along, and wants to listen to it?

Arnold:

No, surely not.

Weart:

OK. Well, then weíll stop.