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Interview of George William Scott Blair by Philip Sherman on 1977 July 9, Niels Bohr Library & Archives, American Institute of Physics, College Park, MD USA, www.aip.org/history-programs/niels-bohr-library/oral-histories/4872
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The development of international societies of rheology, beginning with the formation of the American Society of Rheology in 1929; roles played by Eugene C. Bingham, M. Reiner, Wolfgang Ostwald, deWaele; major advances in rheology since 1925; Scott Blair's career.
Dr. Scott-Blair, can you describe the general state of rheology in 1929 prior to the formation of the American Society of Rheology?
Well, I should say first of all, that there was practically no organization at all. The name rheology hadn’t been knowingly introduced, though in fact it had been used. It had been used because there was a British physicist called Hanney in the 19th century, 1886 I think it was, who introduced the term microrheometer to describe a small viscometer, and then later, in about 1903, there was a German whose name I’ve forgotten — it doesn’t matter — and he talked about rheologie to mean the flow of underground waters. So the term, the word from the Greek, flow, rheo, had been used, but I’m sure Bingham didn’t know that when he reintroduced it to America in 1929.
As you know from the first number of the Journal of Rheology, in 1928 there was a meeting in America at Bingham’s place, at Lafayette College in Easton, Pennsylvania, where they discussed the need for having a special subject, a special branch of physics, with a special name and special organization. Bingham was a very great internationalist, and he wanted this to be an international society, with an American branch, certainly, but with all the other countries contributing their branches to an International Society of Rheology. That was the scheme he and Reiner, who was over there at the time — from Palestine, where he was working for the British Mandate Government of Palestine — discussed with others in Easton, Pennsylvania. But Bingham was the moving spirit of all this.
In Britain there was very little organization; the name rheology was hardly known. I had taken my degree at Oxford, in Chemistry, because there was no possibility of getting a job on a physics degree in those days except for teaching, which I didn’t want to do. I got a job in Manchester working with a firm that made flour milling plant-machinery. I was working on flour suspensions, and I was measuring the flow of flour suspensions through capillary tubes. In those days it was thought that the strength of the flour, that is, its capacity to make a good loaf, depended on its viscosity and the viscosity-concentration relation. Well, this of course was rheology, but the name wasn’t known.
I left that job with a thankful heart, because I hated it, and went to the Rothamsted Experimental Station in 1926. There I was in the Physics Department, and I started measuring the flow of clay-pastes, of soils, through tubes. That of course again was rheology. One day my friend, E. M. Crowther, who was working with me, said: “Do you know what we are doing here is now called by some people rheology?” I’d never heard the word, it didn’t mean a thing to me, and there was no organization of any kind with this name, but he said, “Ah yes, but in America people are already beginning to talk about giving it a name, and it probably will be called rheology.” This was in 1927 or 1928, that sort of period.
In 1929 I got a Rockefeller Fellowship to work at Cornell for a year on what we should now call the rheology of clays, ceramic clays, to relate the measurement of plasticity to the potter’s judgement of plasticity by handling the clay. During the course of that time I was invited by Eugene C. Bingham to give a lecture at Lafayette College, Easton, Pennsylvania, which I did, and I got to know Bingham quite well. Then I went to Washington and attended the first meeting of the Society of Rheology, whose formation had been discussed at Easton, held at Washington, in December 1929. This meeting could well be said to have formally established the special branch of physics called, according to Bingham’s Professor of Classics, Professor Crawford, rheology, the science of flow.
This was not a perfect name, but we had made a sort of adjustment to the meaning of the word so that it should include also elastic properties, because flow is not elasticity and rhea in Greek means flow, of course. Also we made a stipulation that it should not include studies which were not concerned with the structure of materials, in other words hydrodynamics, haemodynamics, and the classical theory of elasticity were not regarded then as part of rheology.
There can’t have been very many rheologists about, because although I was only 27 years old, I found myself to my surprise put in the chair at one of the principal sessions of the Congress, the one really in which the Society was confirmed and the term rheology officially inaugurated. I was also asked by Professor Bingham when I got back to England in July of the next year to start a British branch of the International (as it would have been called) Society of Rheology. I promised to do my best to do that; we will come back to that in a moment.
I cannot remember just how many people were at that first Conference (December 1929). I see from your (RSM’s)  letter to my friend Philip Sherman that two of them are still alive and active. One, Dr. McPherson, I can’t remember, the other is Dr. Hersey. I can’t remember if I met him personally, but do notice that in the first book I wrote on rheology, “An Introduction to Industrial Rheology” 1938, I quote Hersey’s work, a paper that he published on oiliness of lubricants, so I certainly knew of Hersey.
But I don’t know how it came about that a young man of 27 could have had the honour of being made Chairman at the principal meeting of this Society which was founding the International Society of Rheology; the only thing I can think of is that there were so few rheologists at that time, anywhere, in any country, also I had just clashed head-on with Wolfgang Ostwald. I had written a paper in Ostwald’s journal Kolloid Zeitschrift, in which I claimed that his graphs in which he was plotting logarithmic rates of shear against logarithmic stresses was quite an unnecessarily complicated thing to do, and that statistically (and it was very simple statistics) one could get just as good results by plotting linearly with the Bingham model; that is, directly rate of shear against stress with an intercept on the stress axis, and I published this paper.
Ostwald answered, claiming to show that I was all wrong, and you might have thought this would have created a certain tension between us. As a matter of fact, it didn’t in the least. Nor did it create any tension between myself and de Waele, who was a close friend of mine, and of course followed the double-logarithmic plot which Ostwald was also urging. It was only when I was in America that I had a chance to talk to Winslow Herschel, who explained to me that I was thinking along the wrong lines, and so were Ostwald and de Waele and all those other people. I used to think at that time that there was a “correct” equation for studying the flow of complex materials through tubes, and that the correct equation was, according to me, Bingham’s equation, and, according to Ostwald and de Waele, the log-log equation. Herschel pointed out to me that this is quite wrong, that in fact you can make a simpler model with a linear plot such as Bingham used than with a log-log plot, but they are just models and there is nothing particularly inherent in either of them. This I didn’t know at the time. But I think perhaps because I had clashed head-on as a young man with Ostwald who was well known, that they did me the honour of making me Chairman of this meeting in Washington.
Well, when I got back to England I was in a difficult position. Of course I immediately wanted to start a British branch of the Society of Rheology as Bingham had asked me to do, but I thought that I must first go and see my friend de Waele. De Waele was a personal friend, but was a good deal older than myself and senior to myself, and he had also, it seems, been asked by Bingham to start a British branch. Bingham had slipped up there. He had asked two people to start a British branch, one de Waele and the other myself. De Waele was the senior man, so I said to de Waele, “Look, if you will start a British Branch, I shall do everything I can to back you and help you,” but de Waele, although very friendly to me, wasn’t at all keen. He said, “Oh, I don’t know, I don’t think I want to bother much about this,” and he never did. To cut a long story short, he never did anything about starting a British branch of the Society of Rheology. Nor was anything done in any other country; and so in fact, the Society of Rheology, started in Washington in December 1929, became the American Society, and is the basis for the present Society of Rheology, of course.
Then, how did the societies of other countries grow up? I can speak mainly for Britain and for Holland because this happened in both countries at the same time. This was during the Second World War. The Dutch rheologists, Dutch physicists, were restricted by the German occupation from doing certain types of physics, but one of the things they could do was rheology. So they thought it would be a good thing to start a Dutch Society of Rheology, quite unknown to us, of course. We had no communication with them at all at that time. In Britain some people found that there were quite a lot of war problems where rheologists ought to get together and discuss mutual problems. So we started what we rather wrongly, rather foolishly, called the British Rheologists Club. In England a club usually means a place that has an office and a headquarters, but we had no office and no headquarters. I think we should have done as the French did, we should have called it the British Rheologists Group. The French called their society the Groupe Français de Rhéologie, and I think we should have been better if we had used the word Group rather than Club; but it became the Club, and remained so until after the War.
The first meeting that we had was in Reading, where I happened to be working at the time. There were three people mainly concerned. One was Vernon Harrison, who is a close friend of mine to this day. He was at that time Director of the Printing and Allied Trades Research Association. He was working with printing inks, and I was working with mucus from the cervix of cows. Very different things, but the late Herbert Lang, who was then Secretary of the Institute of Physics, was evacuated to Reading because of the blitz on London, and he took this thing up. Land, Harrison, and I started this British Rheologists Club under the Chairmanship of Sir Geoffrey Taylor, and we had a meeting right in the middle of the War, in Reading, at which I think over thirty people turned up.
Now how far, you (RSM) ask in the letter to my friend Philip, was I influenced by my connection with the American Society? Of course, very closely. I'd always felt it was a pity that the American meeting I had attended in Washington had not led to an international organization.
Then, soon after the War, the UNESCO people set up a Committee to see whether the rheological societies of the different countries that were now beginning to form could affiliate under one of the International Unions, or form their own International Union of Rheology. I don’t know who nominated me, but I found myself, together with Professor J. M. Burgers who is now in America of course, representing the International Union of Pure and Applied Physics. We had these meetings at which physics, chemistry, biology and a number of other sciences were represented. We had a lifetime of five years in order to discuss first whether rheology was a sufficiently large science to have its own international union, and if not, to which of the existing international unions should the rheologists be affiliated. We fairly quickly agreed that we were not a big enough organization at that time to form our own International Union of Rheology, but then, when we came to discuss which of the unions we should join, of course it was rather difficult. Burgers and I naturally should like Physics, because rheology is technically a branch of physics certainly. But both of us understood that in fact, although it is a branch of physics, it is so much deeply concerned with chemistry, and biology, and medicine, and a great many other sciences, that it would be invidious to choose one of the then existing unions to which we should attach rheology. So that part of our work didn’t come to anything. What happened was that Burgers and I wrote together a Report on Rheological Nomenclature, which I think was the first of its kind, and this was published by UNESCO.
Well, after that we decided to start the first International Congress on Rheology, which was held in Scheveningen in Holland in 1948, and there we made plans for subsequent international congresses, initially every five years. There was one in Oxford at which I was Secretary, and then they had one in Germany, then one in America. There have been six or seven of these international congresses with either four or five years between them, and rheology has grown enormously. Now we have societies of rheology active in many countries, countries which have newly-started groups of rheologists.
But to return perhaps to my early experiences, when I first started being a rheologist I didn’t know there was such a thing. The word rheology hadn’t been used except by two people whose work had been quite forgotten, and the name rheology wasn’t known. It was just regarded as a branch of colloid science, and I called myself a colloid chemist, as indeed I was; but of course rheology technically is a branch of physics. There was no organization of any kind in Britain. How far was I influenced by the American Society? I think that also is asked in the letter to my friend Philip Sherman. Well, very much, of course, because I had always hoped that the American Society would be a World Society, with branches in other countries including my own. It didn’t happen that way, but I was very much influenced, and I always had my eye on the possibility of starting a British Society. I felt that it wouldn’t be right to do this until I was sure that deWaele was not going to play, and he didn’t — he never did; and I think at the time of the War we felt this was an urgent necessity. De Waele was still alive then if I remember rightly; I’m sure he was, but he didn’t play any real part in all this, and I don’t think he minded a bit that we started up our British Rheologists Club without following up Bingham’s original intention.
Can we perhaps go back now to the 1925-30 period, and I’m going to ask you what other problems were facing so-called rheology at the time, apart from the problems which you have indicated you yourself were working in at the time. I think particularly of the rheology of flow as this was an eventful period when the Ostwald-deWaele equation was developed, and there was much interest and discussion of its validity.
I think the main point there was that we, I quite wrongly, and I think the other people who are now called rheologists were of the same opinion, thought that there was a kind of mystique about the equations for flow, that I knew had to have a linear equation which followed the Bingham picture, and that of course goes back to Trouten, or you had to have a double logarithmic approach which was that of Ostwald and, more complicatedly, deWaele. I thought these were real things. As to work that was being done, after the classical work that was spaced out over the years from the time of Poiseuille in the 1830’s, and a few people like Hanney in the 1880’s, not very many people did what we now call rheology. There was extraordinarily little done. It was generally regarded, insofar as it was thought of at all, as just a branch of colloid science, I think.
Your own interests in rheology as applied to foods, I believe, began in the early 1930’s. Is it possible for you to say whether in fact for this particular period there was any interest in food rheology, or applying rheology to the study of food texture?
Well, when I came into the field of food it was when I went to Manchester. After I got my degree at Oxford I went to this job with the flour milling people up there. Sharp was one of the principal people concerned, and he was trying to show that viscosities of suspensions of flour, either the viscosity or the viscosity-concentration relation later, was a measure of the capacity of the flour to make a good, well-structured loaf, strong flour as it was called. And I did a lot of work at the time, between 1924 and 1926, on the flow of suspensions of flour through tubes. That type of work was quite common at that time. And I think quite a lot was being done there. Very little was done on other food stuffs, as far as I know, rheologically, in those early days, as far as I can remember. By the way, this is another point, but it did occur to me. Talking about other people who may be still alive who were at the meeting in Washington and might help you with reminiscences, you mentioned two. McPherson I don’t know at all. I can’t find any record of having met him or having recorded any of his work. Hersey, yes. I don’t know that I met him personally. I probably did, in Washington, but it’s so long ago I can’t remember. But I did note that in my first book I mentioned his work on the oiliness of lubricants. He may be able to help you better than I in memories of the first meeting.
It (the December 1929 meeting) was a very cordial meeting. Although it was not a very big meeting, we had people from an amazing variety of disciplines. I remember some people from a toothpaste factory, and there were medical people, and there were plastics people — of course not in such a high proportion as there are now — and there were people from all kinds of diverse disciplines, although the whole meeting must have been a comparatively small one.
Yes, the list of Editorial Board members of the JOURNAL OF RHEOLOGY which was initiated soon after that time does also tend to confirm the very wide range of interests, the application of rheology to various products. In fact, the majority of the editors were chemists rather than physicists. Would you say on the basis of your own experience, that there seems to be some sort of narrowing in the interests in applying rheology to diverse products compared with the 1925-35 period?
Well, I think yes, in a way. I think it is true that in the days when I was a young man — I was a chemist by training and most rheologists were chemists. One or two were engineers; Markus Reiner, for example, who goes back to the earliest times although it happens that he was in Palestine in 1929 and was not able to be at that meeting. But he had been with Bingham in 1927-28, and again with Bingham in, I think, 1930 and ‘31 — I’m not quite sure of the dates, but no matter about that. But he was not there in 1929. Markus Reiner was an engineer by training. But the great majority of people, although rheology is clearly a branch of physics, at that meeting were chemists. And this is one reason, perhaps, why we were all a little afraid of advanced mathematics — because the mathematics of rheology in the days of Bingham, who was a chemist of course, were extremely simple. And nowadays if I look into — I can’t see to read as my sight is extremely bad — but if I get someone to read to me out of a modern book on rheology, I find it highly mathematical and very advanced mathematics. It’s become much easier now to regard rheology, as it should be regarded, as a branch of physics than to regard it simply as an offshoot of chemistry.
Can you recall at the time of the first meeting or around about that period, any discussion of the possibility of introducing formal courses in rheology at the universities or polytechnics?
No, I can’t remember anybody suggesting that, but of course it may have been suggested — it’s a very long time ago. But I don’t remember any suggestion of that kind at the time.
Can we come back perhaps for a little while to this first meeting, and ask if you can recall the types of subjects which were covered in the presentations there?
Well, I think you can see that best by looking at the papers in the first number, or two numbers, of the JOURNAL OF RHEOLOGY [ED. NOTE: Actually in Vol. l, Nos. 2 & 3], which had such a short life unfortunately. There were many papers there, there was one by Markus Reiner, one by myself, quite a number of other papers on all kinds of different things. I think dental compounds, foodstuffs, plastics to some extent but not so much perhaps as now, and in my own case of course, clay — I was interested in that at that time. I think it was very widely diverse. But I can’t tell you more than would be seen if you look at the early numbers of the JOURNAL OF RHEOLOGY.
Can I ask you, too, whether there was any particular reason that the Society of Rheology originated in the States rather than one of the European countries? There were, for example, on the list of Editors, Professor Kruyt from the University of Utrecht in Holland, and various people in Germany. It seems a little surprising that there was not an effort to initiate such a society in one of the European countries before 1929.
I think the reason for this was the personal energy and enthusiasm of two men. One was Eugene Bingham and the other was Markus Reiner. One was in America, and that was the obvious place to start it, and the other was in Palestine which was then a British mandate. And I think it was these two men who were mainly personally responsible for the initiative in starting something. Ostwald, of course, did a great deal of rheology, and published very many papers. But I don’t think there was any suggestion of starting a society in Leipzig as far as I know.
Ostwald did one rather strange thing, considering that I had criticized his work pretty drastically and for a young man rather cheekily if you like. Just before the war, in 1938, I published my book, and he suggested that he should make a German translation of the book. And he rushed through the translation and got the proofs across to me, which I corrected on my way across the Atlantic, by ship in those days, of course, in the summer of 1939, just before the war started, and got them back to Germany. And I had the satisfaction of hearing from the Deutsche Rheologische Gesellschaft rather recently that the setting up of a society of rheology in Germany had been considerably helped by the people after the War when things had settled down again, reading my book in German. So I was rather well satisfied to have helped to get this society organized. As indeed I helped to get organized the society in France, because I worked a great deal in France. And in France the people were working on so many different materials on rheology. There were many rheologists, but they didn’t seem to me on the whole to cooperate very well with people working with materials other than their own. They tend to think along material lines rather than subject lines. The two people who really made the Groupe Français de Rhéologie were neither of them in the strict sense, French. One of them was Madame Daubry-Duclaux, who was a Russian-born wife of Professor Duclaux, a very distinguished French professor in Paris, of course. And the other was Dr. Weiss from Alsace, which is, of course, certainly France, but perhaps not the most typical part of the French nation. And these two people between them really got the French Group going. So I think France has been a little bit difficult, because the French people tend to think very much more in terms of materials rather than subjects. Now of course, as you know, branches have started in Italy and many other countries. Those countries now have their rheological societies.
Can we also refer back for one moment to the 1929 meeting again, and in the list of original members of the society I notice your name appears among the American members. Can you explain the reason for that?
Oh yes, the only reason I can think of, and it’s purely guess work of course, is that I had a Fellowship at Cornell for one year. And this meeting in December came halfway through my Fellowship. And I suppose they thought of me as a Cornellian at the time. That was probably why. I was coming from Cornell and going back to Cornell. I actually was in the United States from summer to summer, and the December meeting was just in the middle of my time there. So I was perhaps taken as an American temporarily.
Would you like to say perhaps a few words about the work you were carrying out at Cornell?
Well, yes, I will do so if you like. I was working with — I’ve forgotten the name now, it was a glass factory somewhere in northern New York State. And what I wanted to do was try to find a measure…
Corning Glass, I’m not sure. Might well be. But anyway, they supplied me with samples of clay, potters’ clay. And what we did was to get potters, good potters, to judge the plasticity of those clays, and to score them in order of plasticities. Now I took those clays and mixed them up and made them into pastes. I pushed them through capillary tubes. And I found I could get a fairly simple relation between a kind of Bingham treatment of those clays, a rather complex Bingham treatment, and the plasticity of those clays as judged by the expert. And in fact all my working life from the days when I started on flour doughs in Manchester right through the time in America working on potters’ clays and much later on again flour dough, and on cheese and on various medical materials, I’ve always tried to relate the judgement of experts handling things to what you can measure on instruments. That is what I was trying to do when I was in Cornell. And I published, during the course of only a year’s work there, I think about five papers, under Professor Wilder D. Bancroft, who was a very inspiring leader. And I did find a rather complicated but unexplained, completely unexplained way of measuring the plasticity of a clay in terms of the curves that you got plotting rate of shear against shear stress. When I came back to England I was invited by the British Ceramics Society to give a lecture on this, which I did. J. W. Mellor was the leading light at that time, but he was unfortunately not well then, and he couldn’t attend the meeting. But I got a very poor response. The people there were really frankly interested in nothing more than how much money I could make for them by my invention, which was perhaps not very much. And so I don’t think the matter was followed up at all. And I think it’s entirely lost now. I’ve never heard of anybody using this method any more now.
When you mentioned that the British Society was formed in the middle 1940’s, I presume that during the War or immediately after the War there was very little if any contact with the American Society.
Not really very much during the War, no. We couldn’t have very much. And of course we had absolutely none with the Dutch Society. Immediately after the War the Americans came to the first meeting in Scheveningen in Holland, in 1948. I met my very close friend, Al Copley, there, an American. And many other Americans came to that meeting. It was very noble of the Dutch to organize it, because they were still feeling the after-effects of the occupation, and the country was in a very, very impoverished condition. But they managed very well. I think my friend Burgers worked awfully hard on this, and did very well with it. But that was the first time I met Americans at all much (apart from one or two during the War) since the days before the War when I was over there. I went again on a second trip to America, you see. I had my year’s Fellowship in Cornell, 1929 to 1930. Well then in 1939, just before the War started, my wife and I went over to America and I went on a lecture tour on rheology, round very much the same territory that I’d covered in my Fellowship. That is, I didn’t get out far West. There weren’t so many rheologists out West at the time, and I hadn’t the opportunity of going way out to the West. I didn’t go to the deep South. I kept within an area, broadly speaking, from New England about as far as the Mississippi and then down to Richmond, Virginia. But that’s as far as I got on either of my trips. On both occasions it was that part of America that I visited.
I recall too from my early visits to the British Society of Rheology meetings during the 1950’s with deWaele who was my Director of Research at that time, that the range of topics which were covered at any one meeting were very restricted. Very often there was just a single lecture, possibly two. And there certainly didn't seem to be the spectrum of interest that apparently was covered in the original 1929 meeting of the American Society of Rheology.
I think that’s very true. I quite agree. I think it started — restarted — again very much in Britain. I don’t think many of the people who came to our first meeting in Reading during the middle of the War knew much about the meeting in America that I had been fortunate enough to attend in 1929. Certainly, Sir Geoffrey Taylor, a very eminent rheologist, hadn’t thought of himself as a rheologist particularly before that, though his work in rheology is, of course, well known.
It appears from the minutes of the American Society of Rheology that there had been a proposal around about 1948 to ‘50 to establish an International Union of Rheology, and that this proposal had been opposed by the British Society and also the American Society. Would you have any recollections of that period and the reasons for this?
Well, I think that’s not quite correct. I think this is a little bit confused about this international commission that was set up by UNESCO, and on which Burgers and I represented the International Union of Physics. We there did have to consider whether it would be worthwhile having an International Union of Rheology. And it was decided by all of us — this was not a kind of veto on the part of Britain or America or both or anything like that — it was agreed by everybody there that it was not yet time to have, and it’s not yet even now time to have, perhaps, an International Union of Rheology. Maybe the time has come now, but it hadn’t then. We certainly felt it was not time. But I don’t think there was any opposition to it except in the sense that we just felt that our science at that stage, in 1948, wasn’t sufficiently developed to justify the setting up of a union. Unions were connected at that time with very big branches of science, and I don’t think we felt that rheology was at that time sufficiently large or well established to justify making a separate union.
Now if we compare the stage of knowledge in rheology at the present day with that of the time of the first meeting of the American Society, can you from your recollections of the period intervening indicate what you regard as being the major advances in rheology since then?
Hmm. That’s a big question, isn’t it, Philip? I think I would say that the first thing that has happened is that rheology has taken its place now firmly and securely as a branch of physics, and also mathematics, because we now have mathematicians who are prominent rheologists. And this is a very great help. In the early days, as I said before, we were most of us chemists like myself, chemists by training. I had, of course, some training in mathematics with my chemistry. I knew how to do simple calculus and all that kind of thing. But the kind of mathematics that comes into advanced papers on rheology now — well, I learned mine very largely from my friend, the late Markus Reiner, who was an engineer by training but whose mathematics was very good, although he would never have claimed to be a mathematician. But I think the biggest advance has been the introduction of mathematical methods. We hardly used tensor theory, you see, in the early days. It was hardly known, it was hardly understood-by rheologists I mean. Well, now it’s absolutely de rigeur, everybody uses tensor theory, of course, and much more difficult mathematics. And all kinds of advanced mathematics are now applied to rheology. And it even links up with such remote branches of physics as relativity. And I think this is just as well. I think rheology has expanded its outlook very much through the introduction of partly statistical and very largely mathematical techniques.
Yes, and I suppose too one should mention the whole field of psychorheology. Perhaps intentionally, in all due modesty, you omitted that, seeing of course, that you pioneered it yourself. It is of very great interest now amongst food rheologists, pharmaceutical chemists, and cosmetic chemists in particular.
Yes, I did as a matter of fact rather pioneer this psychorheology, I think, because when I was working at Rothamsted Experimental Station on flour doughs I found out a lot about the dough, but I couldn’t find out a lot about the baker. And it happened at that time that a very distinguished European psychologist, David Katz, had to leave Germany because of the Nazi regime, and he was not yet appointed to his chair which he later got in Sweden, and he had about a year or something to spare in Great Britain. He came and joined me in St. Albans where I was working, and we worked there together. He studied the baker and I studied the dough, and this worked extremely well. Well, this so much impressed me that when I went to Shinfield, Reading, to the National Institute for Research in Dairying, and was told that what they wanted me to do was to compare the assessment of quality of, particularly, cheese and other dairy products in handling them and eating them and so on with physical tests, rheological tests, I said, “Yes, but look here. If I’m going to do this I must have two additions to my staff.” In those days one could think of additions to staff. I know it’s not popular now, but one could in those days. I said I wanted, first of all, a good colloid chemist. And I got one, Rudolpho Schaffenberg, who was a refugee and is now living quite close to me here in Oxford, retired, but still doing splendid work in one of the labs here. And the other was a young girl who was well qualified as a psychologist. She's now married, but her unmarried name was Dr. Valda Coppen. She was the psychologist, and she and I worked together on a study of the cheese maker from the rheological point of view. And my wife had happened at that time to change from being a historian to being a psychologist, so I used to go with her to meetings of the British Psychological Society, so that I could learn as much as I possibly could about general psychology. And I think that my colleague, Valda Coppen, also learned, in fact I know she learned, as much as she possibly could about rheology, and we worked together very happily.
I suppose too as a result of the work carried out during the Second World War there has been a major upsurge of interest in polymer rheology, so that perhaps this has become the subject of primary importance within the field. Although certain aspects of polymer rheology can be applied in other rheological fields, the overwhelming interest and activity seems to be in that field now.
Oh, I quite agree. Absolutely. I had a book sent to me as a present the other day from Moscow, from Vinogradov, who is a well-known rheologist, as you all know, on rheology of polymers, in Russian. But in Russia, particularly now, most of rheology is on polymers, I think. We have an editor of Biorheology, the journal of which I am co-Editor in Chief, Vorob'ev, in Leningrad. But he sends us very little stuff, because in fact, very little biorheology is now done in the Soviet Union, whereas in the West, biorheology is now a very important branch of rheology. And there is more and more medical rheology. I think rheology is developing into medicine far more now. In the early days there was one man who came to Washington to that meeting, the name for the moment eludes me, it may come back before the end of this interview — I don’t know — who was medical. But on the whole, there was very little medical rheology. Now, on the contrary, there is a great deal of rheology in medicine. And we have in Oxford a Department of Medical Engineering, which comes very close to medical rheology, of course.
Finally, if we can once again go back to the first meeting, and your stay in the States, presumably at that time you did meet Professor Bingham and were involved in discussions with him. Can you, perhaps, give us your personal recollections of Professor Bingham?
Yes, I can give you quite an amusing story of how I actually physically met him for the first time. To my great surprise, I had a letter from him when I was at Cornell — he was at Lafayette, of course — inviting me to go to his University to give a lecture on rheology. And I was, as I say, a very young man and more or less unknown, and I felt very much honored that I should be asked to go down there. But I was a Rockefeller Fellow, and one of the conditions of my Fellowship was that I must send to the Rockefeller office in advance, a little bit in advance, an exact statement of expenses I was going to incur on invited travel, and they would refund me the money. This was very good. So I wrote to Bingham, asking if he would kindly send me a formal invitation that I could send to Rockefeller so that I could be refunded the necessary money to go down to Easton, Pennsylvania from Cornell, from Ithaca. Well, in fact, I didn’t hear from him, and I still didn’t hear from him, and I still didn’t hear from him. So when it came very near the time, I sent him a cable saying something to the effect that I presumed that since he hadn’t answered my letters he didn’t want me to go. And then, I presume I heard something to the effect that I was mistaken in that, and so my wife and I set off from Cornell and went down to Lafayette College. The first thing I saw when I got to the campus, and made my way along to Bingham’s laboratory — I was shown where it was of course — was a note on the door saying that Dr. Scott-Blair’s lecture is cancelled. Well, I met Bingham, who was perfectly charming, a delightful person. And he said, “You know, I’m awfully sorry, but there’s been a muddle, and I didn’t understand your letters and I thought you weren’t coming.” Well, as a matter of fact, I had a very small audience for that reason, but I did have a chance to meet Mrs. Bingham, and we liked them very much. He was really a great man, Bingham. He really was. He was a man of very, very world-wide ideals, and I admired him very, very much. The only pity was that he wore himself out, and I think he wore his heart out, because, as you know, he died from heart failure eventually, from simply working so hard for science, and for international science, and for peace. I admired him enormously. It was a very great privilege that I felt that he would regard me, as a much younger man, as worthy to be invited to lecture to his students.
My friend Philip has reminded me of one very well-known rheologist who was a close friend of mine. Philip met him, but I think he was a closer friend of mine than he was of Philip perhaps; though he doesn’t come into the American picture so much. That is J. Pryce-Jones. Pryce-Jones was a Welshman, very Welsh, and very proud of it, rightly. He worked for Reckitts, the firm up in northeastern England. He suffered a great deal from insomnia. He was not at all a strong man physically. And he’d arranged with his firm that whereas he did industrial work during the day for the firm, at night he worked in a lab which they helped him to equip, on rheology. He did a great deal on rheology; as you certainly know. I don’t know of his having any particular connection with international affairs or American affairs, but he was, of course, a very distinguished rheologist in his own field.
I should have mentioned also Pryce-Jones’ work on honey. I myself worked on honey for quite some time. We have in England a type of honey which is not known in America, I believe, from the plant known as calluna vulgaris, which is a type of heather. And this honey is highly thixotropic. Because it’s thixotropic, bubbles of air form in it which can be quite large bubbles, and as long as they are large bubbles, the whole system appears very attractive. It’s quite like a jelly, and then when you shake it, it becomes runny, of course, when you spread it on the bread. The price of the honey depends very much on the extent of the thixotropy, and Pryce-Jones and I both developed methods of measuring the thixotropy of heather honey. I came across a rather surprising connection here. We went down, the British Society of Rheology, to Devonshire in the southwest of England, where there is a monastery, and the monks there have one of the biggest productions of honey in Britain. I met the Prior there, and we met all the monks and people, and there they showed me the machines that they have for breaking up the thixotropy of their honey in order to get it out of the honeycomb. Pryce-Jones was the leading man on the thixotropy of honey.