James Douglas (Jim) Morrison was born in Glasgow, Scotland in 1924. Morrison completed his higher education at Glasgow University with a BSc (Hons) in chemistry (1945) and a PhD in X-ray crystallography (1948). Morrison was also awarded a DSc from Glasgow University in 1958. In 1949 Morrison left the cold and gloom of Scotland for sunny Australia and a position as a research officer in the division of Industrial Chemistry at the Council for Scientific and Industrial Research (CSIR). At CSIR Morrison changed his focus from x-ray crystallography to mass spectrometry, with great success. One of his major achievements in the field of mass spectrometry was the use of a theoretical deconvolution computer program to sharpen the peaks in mass spectra in 1959. While at CSIR, Morrison was promoted to senior research officer (1953), principal research officer (1956), senior principal research officer (1960) and finally chief research officer (1964).
The newly established La Trobe University in Melbourne offered Morrison the foundation chair of physical chemistry, which he took up in 1967. In 1985 Morrison became the chairman of the Chemistry Department at La Trobe University and was made emeritus professor in 1989, upon his retirement. During his career Morrison went on several fruitful sabbaticals, visiting the University of Chicago (1956-57), Princeton University (1964) and the University of Utah (1971-72), where he became an adjunct professor of the Chemistry department (1973-2001). He was also the first master of Chisholm College at La Trobe University (1968-70).
Interviewed by Professor Anthony Klein in 2010.
When and where were you born?
I was born on 9 November 1924 in Glasgow, Scotland—and, very shortly after that time, my parents moved to Broughty Ferry, a small place near Dundee, on the estuary of the River Tay where it flows into the North Sea on the east coast of Scotland.
Tell us a little about your parents.
My father was Scottish and he was a soldier in World War I. That’s when he met my mother, who came from Yorkshire, and they got married in 1923. At that time he was a clerk in the Vacuum Oil Company, which subsequently turned into Mobil. In fact, he started off as an office boy and rose to be a very senior executive of that firm.
What about your boyhood and the influences that turned you towards science?
I spent a lot of time roaming on the sands near Broughty Ferry and had a marvellous time. I made friends with a local scrap merchant and he gave me bits of machinery, like old car magnetos, which were able to produce large electric sparks. I think my favourite reading matter at that time was the Boy’s Own Paper, which had jolly good yarns. And, what was more important to me, they told you how to make your own fireworks and how to build your own crystal radio sets. Of course, in those very happy days, you could go to a chemist’s shop and buy all the materials to make your own gunpowder. This was a great help to a boy who might think of becoming a chemist. Another thing I learned from the Boy’s Own Paper was how to do bookbinding, which has been a hobby that I’ve enjoyed right up to the present time.
And the influences that brought you towards science?
I had an uncle who was an engineer in charge of what was effectively a small town. He was in charge of an electric generating plant, a water supply, a cinema—everything—and I used to go and stay with him quite often. He showed me how to use a lathe and other tools in the workshop. I was always tremendously impressed by the workmen; by the way they looked after their machines.
Then, of course, another person who had a great influence on my life was my English grandfather. My Scots grandparents were a grim pair, but not my English grandfather. He’d been born in the Cotswolds by a small river called the Windrush, near Bourton-on-the-Water. In those days, people who lived in the country in England gathered their own herbs to make their medicines. He used to take me out to find herbs and gather them. He also knew how to find wild animals, like otters and badgers and hedgehogs, and I enjoyed my time with him very much.
I think the favourite books I had to read—well, there, I think I was most keen on HG Wells’ science fiction and how science was going to save the world. My Scottish great-uncle gave me books on archaeology, one rather odd one: at age nine, he gave me Adam Smith’s The Wealth of Nations, which I must admit I found pretty heavy going.
What can you tell us about the schools that you went to?
I went to the Scottish academies—the Morgan and Grove academies, near Dundee. Then, when my parents moved to the west of Scotland, I went to the Lenzie Academy; that was when I was 13. I liked school very much; it was a wonderful time for me. But one thing I discovered in the west of Scotland was that you had to be bilingual. That is, I had to speak English at home but at school I had to learn to speak Scots. Otherwise, you’d have your head knocked off.
Well, that explains it, because so many of your Scottish scientist colleagues in Australia need subtitles, they speak with such a thick Glasgow accent, which you don’t have.
I think people are a little kinder here than they were in the west of Scotland [laugh].
And what about your teachers?
I enjoyed them very much. In Scotland, teachers that taught up to the last year of school had to have what was called ‘chapter 5 qualifications’. This meant that as a minimum they had to have an honours degree in the subject that they taught. I liked them very much. Of course, another aspect of education in Scotland was that they believed very much that a leather strap was a jolly good inducement to learning and memory. In fact we had an English master who thought that every Scots boy only used a tenth of a percent of his brain power, and that if you belted him, you could enliven another tenth of a percent. As a result, I can recite to you most of Chaucer’s prologue: “Whan that Aprille hath his shoures sote, the droghte of Merche had perced to the rote”, and so on.
The war started in my third form at school, which made a difference to life. There was no sport at school any more. We all had to do two nights of fire watching in the school, every week. This meant that you were given a bucket of sand and a long handled shovel and told that, if an incendiary bomb fell through the roof, you had to cover it with sand and get rid of it. Luckily, we didn’t get any incendiary bombs at our school, but we did get a shower of shrapnel from the anti-aircraft shells. Another very good thing for me during my school days: I had a friend whose father worked with Barr and Stroud, an optical company. He gave me reject lenses, with which I was able to make my own telescope and my own camera and enlarger.
Glasgow University shrouded in mist
And, towards the end of your schooling, you caught a glimpse of Glasgow University and you decided that you were going to get there, if you possibly could.
Yes. When I was about 13, my father and I drove to Glasgow and I saw this wonderful building in the mist. At that time in Scotland you got a lot of mist—there were these beautiful buildings in the mist—and I’d made up my mind, by hook or by crook, I was going to get there, if possible.
And you did.
I did. I entered university in 1942, in the middle of the war. What was a great help to any Scottish boy at that time was that the Carnegie Trust gave £50 to any Scottish boy who wanted to go to university, and that was a tremendous help to my parents. At the time I started university, there were only science, engineering and medical students, because all the arts ones had been conscripted into the army, Also, we were given only two years and nine months deferment from military service—that was to complete a fouryear honours degree. The way the university achieved this was by cutting out all the vacations. Thus, the minute you’d finished the nine months of one year, you then started immediately the next year. So that, they reckoned, in two years nine months you could cover the whole four-year degree.
Well, even at university it was pretty tough because you had lectures and labs on Mondays, Tuesdays, Thursdays and Fridays, and on Wednesdays, Saturdays and Sundays you had to do military parades, where you got military training as well. In a way I quite enjoyed the military service. They taught you how to use explosives. I think they had some idea of turning us all into guerilla fighters because they showed us how to use plastic explosives and shaped bombs. I never found any use for it later, but it was useful information at the time.
What impressed you most in your undergraduate years?
I think it was my first-year professor, JM Robertson. He’d been at the Royal Institution in London and came to Glasgow as his first teaching job. He was a very shy, retiring man, but he showed us a wonderful slide of a huge molecule; [whose structure was determined] using X-ray crystallography. He’d managed to show every single atom in the molecule. Nobody had ever seen anything like it. You see, at that time molecules were hypothetical things. We knew what their structure was, but nobody had ever seen one. Here, suddenly, JM showed us a picture of one that he’d actually produced by this means and this, of course, inspired me to go for X-ray crystallography.
I also met this very charming young lady in the same lab, doing the same honours course of chemistry. I was very attracted to her and she subsequently became my wife.
Wonderful. So, when did you graduate—after the war?
I graduated in 1945. By that time, the war had just ended in Germany, so we were told that we weren’t needed for the army any more and instead we had to go and find a job in industry. But I’d set my heart on research, so I applied for a PhD degree.
Post-graduate studies in X-ray crystallography
How did that come about?
I went to see JM Robertson, whom I’d admired all through my course. I think JM must have been impressed by my enthusiasm because, after thinking about it, he said, ‘I can only offer you £50 for the year as a scholarship, but you’d be welcome to come and join my research group.’ In that way, I joined six other research PhD students in his group, one of whom was Sandy Mathieson, who became a very good friend, best man at my wedding and, subsequently, came to Australia. He influenced me to come to Australia and then he also became a member of this academy.
So did you do well in your research?
In my first year, I discovered that you could find hydrogen atoms by X-ray crystallography. You see, hydrogen’s only got one electron and, since X-rays only see electrons, nobody had ever thought that you could find hydrogen. I did manage to find it! I think this must have impressed JM because he almost at once gave me an assistantship—a very junior post in the university. In those days to get an X-ray structure it needed huge calculations. You didn’t have computers; you had to do it all with mechanical computing machines. So, to get a single structure, it would take you, oh, up to six months to do it.
And then you wanted to marry Christine?
Well, I had kept up with Christine. She’d gone off into industry to work for ICI (Imperial Chemical Industries). I went to see JM to see what he thought about getting married. Well, poor old JM gave me an hour’s talk on the evils of early marriage for young scientists, but he seemed to give in, in the end and, in fact, he gave me a small promotion.
So what were your job prospects then?
I didn’t know. It had already dawned on me that good jobs in Britain went to Oxbridge graduates and all the rest were second-raters. So, I wasn’t going to put up with this; I was prepared to look elsewhere.
Further afield, like Australia.
New opportunities in a sunlit country
How did that come about?
At that time, from 1944 to 1948, the weather in Scotland had been dreadful. It was mist and rain all the time and the sun never shone in Glasgow. Also, there was a young Australian ICI fellow in Glasgow, called Geoff Badger, and his wife, Edith. They became friends with us and they showed us a book of pictures of sunlit Australian beaches, which had a tremendous impression on us in Scotland. Then, in 1948, we had a visit to the lab of a little chap, Ian Wark, who told us about a new lab he was setting up in Melbourne. Sandy Mathieson and I were very impressed by Ian Wark. We thought he sounded like a good sort of fellow. Sandy, was just finishing his PhD, so he applied for a job and was appointed in CSIRO—or CSIR in those days. I’ve got letters still from him writing back, telling us about this wonderful new land. When I got my PhD the next year, I applied also and also got a job in CSIR.
Tell us about CSIR and how you found it.
CSIR was the Council for Scientific and Industrial Research and it had been set up in 1924 to carry out research in primary and secondary industry. In those days there wasn’t much secondary industry in Australia, even in 1948-49, when I joined it. But Ian Wark had been put in charge of chemistry and he set up a section, which later became a division called Chemical Physics, and this is the one that I was to join.
We’d better clarify just exactly what is meant by ‘Chemical Physics’.
In the 1940s, chemistry and physics were taught in the universities but were pretty well mutually exclusive. You either did a degree in chemistry or you did a degree in physics. I think it’s a great credit to Ian Wark that he realised that physics could be used more widely. During the war, there’d been tremendous advances made using physics to make weapons of warfare of all sorts, and I think it was Ian’s idea that you could perhaps find lots of other ways in which physics could be used, particularly in chemistry. He was fortunate to find another young fellow called Lloyd Rees, to set up this new section. What Ian then did was to invest in all the latest pieces of physical instrumentation of all sorts and then set about finding young men who would come to do something with these instruments and see how they would turn out.
And what was your task? Was it in X-ray crystallography, which you trained in?
There were not many of us in that section. Sandy was doing X-rays and we had John Cowley and Alec Moodie who were doing electron-diffraction and Alan Walsh doing spectroscopy. All of these were very successful. Sandy had come out to do X-ray crystallography. I was an expert in crystallography too, but Ian Wark took me aside in his office and said, ‘You know, we’ve just acquired a mass spectrometer from the United States and we think your job should be to see if a mass spectrometer would be of any use in chemistry.’ There were very few mass spectrometers in the world at that time; I think there were ten in the United States, one in Britain and none in Australia. The only place where you could find such things was where there was lots of money, which were oil companies and governments. One huge mass spectrometer had been built in America—in fact, not just one; I think they built several huge mass spectrometers called calutrons in order to separate uranium 235 from uranium 238 to make the first atom bomb.
At that time the United States government had placed an embargo on mass spectrometers. They said, ‘You could maybe use a mass spectrometer to make atom bombs, so we’re not going to sell them to anybody else.’ It so happened that Ian Wark managed to get John Curtin, our Prime Minister at the time, to write to Harry Truman. I believe there was some correspondence back and forth, after which Curtin got back a letter from Truman saying, ‘In recognition of our successful collaboration in the Battle of the Coral Sea, we’re going to give you one.’ So that’s how we acquired the machine that I was given.
But I think that machine would have taken 250 million years to make a gram of uranium!.
Well, not quite. I once did a few calculations just to see and I reckoned it would have taken me 500,000 years to produce enough 235U to make us a successful bomb. So I think they were a little bit overworried about it.
I think we’d better describe exactly what a mass spectrometer is.
It’s really not a very complicated machine. JJ Thomson, an English ‘physicist’—I guess you would call him—in 1910 or so discovered that, if you struck an electrical discharge in gas at low pressure, you got a coloured glow and this coloured glow consisted of ions of atoms or molecules that had lost an electron and had an electric charge. He also discovered that these particles could be deflected in a magnetic field and that heavier particles were deflected less than light particles, like hydrogen. Hydrogen particles were deflected very easily and the heavier atoms less so. So, by that means, he discovered that there were two kinds of neon. Up till then, they’d just known of a rare gas called neon. Here he suddenly found two neons, one at mass 20 and one at mass 22, which they called isotopes.
JJ Thomson had two research students—one, Aston, a young Englishman; and Dempster, a young Canadian—and they took this idea of JJ Thomson’s and developed it. Aston built what are called mass spectrographs, where they used photographic plates to detect the ions, whilst Dempster used electrical methods of detection to produce what are called the mass spectrometers. By 1944, these machines had been made with a mass resolution of about one in 250. That is, you could separate atoms with masses up to molecular weight 250, which was just enough to separate the uranium for the atom bomb. But like radar and so many discoveries that were made in England, the commercial applications of it took place in America. In fact, this was where commercial mass spectrometers, while there were very few, were being produced at that time.
So your first task was to tame this new beast that was imported from America.
There was a little more to it than that because they were very difficult machines to get working at all. You see, they have to have a high vacuum and the vacuum pumps that we had were very primitive. They used a lot of electronics—and, in those days, electronics itself was a black art. As a result, I think there were only 25 of us in the world who had mass spectrometers and we all became very close friends. Unlike today, where somehow people are all out for themselves, in those days we helped each other with advice on how to keep your machine working.
So, for chemistry, what could one do? If you take an atom and ionise it, all you get is the atom with a plus charge on it. But, in the case of molecules, they break up so that, for example, if you have carbon dioxide (CO2), you don’t get an ion just at mass 44 corresponding to the mass of CO2 but you also get an ion at mass 28, which is carbon monoxide (CO), an ion at mass 16, which is oxygen (O), and another one at 12 for carbon (C). If you had a more complicated molecule, nearly every chemical bond broke and you got this pattern of ions, which we call a mass spectrum. Here again, these were very characteristic and could be used for identification. But it wasn’t as simple as that either, because the spectra that you got were not always the same; they depended on the temperature of the ion source we were using, they depended on the gas pressure and they depended on the voltages that you used in the instrument. My first job was just to study how ions are made and see if we could produce reproducible mass spectra.
So these mass spectra are essentially a graph with particular lines showing the different fragments.
When you put a molecule into the mass spectrometer, some of the molecules just produce an ion with the plus charge and some of them break bonds so that you get all these various fragments. The mass spectrum comes out as a piece of paper with a list of peak heights versus mass number, which is characteristic of a given molecule.
So what was your first great success?
Bob Robertson, who ran the CSIR division of Food Preservation and Transport in Sydney, came to us. They’d been studying the way apples in storage tended to go bad. It was his idea that the apples breathed and that something in the apples’ breath was causing decay. So his chemists had separated out the breath of Granny Smiths and sent it to us and we put it in the mass spectrometer. It was a bit of a job because one drawback to a mass spectrometer is that a sample has to be pure. If you have a mixture of two things, you don’t just get one parent ion and a whole lot of fragments; you get two parents and all the various fragments that both of them could break up into. So trying to interpret it was rather like trying to solve two sets of jigsaw puzzle bits that had been tipped out into the one tray, and sorting out which was which was quite difficult. But, even so, we managed to find out that the apple breath consisted of a mixture of esters and some ethylene, which apparently made the food preservation folk very happy.
So the esters are what give the green apples their smell and the ethylene is what makes them ripen.
Apparently. Ethylene has since been found to be very effective for food ripening. If you have ethylene gas given off by one fruit, it will make all the other fruit in its neighbourhood start to ripen.
And you were the discoverer of that?
Well, I wouldn’t say that, but we certainly found the ethylene.
So what were the challenges? Obviously it was much more complicated with all these fragments and different masses and so on to put it all together to deduce what molecules were in the gas.
Yes. First of all we had to discover what was the mechanism of ion impact. To make an ion, you have to bombard the molecules with a beam of electrons. When you do this, first of all, if the energy is low, you just produce the molecular ion. Then, as the energy gets a little bit more, you break the weakest bond in the molecule. Then, as you turn up the energy of the electrons more and more, you can find more and more bonds and break them until you’ve finally knocked about every atom off the molecule and found all these various bits. Well, I thought it would be a wonderful way to measure bond energies. By varying the energy of the electrons, you could control them in this way: gradually, as you find the weakest bond and break it, you find that fragment and so on.
It turned out to be a bit more complicated than that because none of the thresholds were sharp, for example. They all seemed to start off with a slow curve that rose up from a threshold, and we had to find out what it was about the impact process that did this. I suspected that it was due to the fact that, when you pass an electron through a hole in a metal plate at 10 volts, you thought you’d got 10-volt electrons; well, you haven’t. You’ve got electrons with a spread from 10 to 12 volt, and I think this was partly what was smearing out our structure. So I spent years trying to build monoenergetic electron sources, where you got a beam of electrons with one energy.
So that the mass spectra are sharper lines rather than broader peaks which overlap and confuse the issue?
Yes, and we built a lot of electronics. That’s where, in fact, I was very fortunate to be given two young female assistants, who I trained to use a soldering iron, and they turned out to be very successful at building electronics for me.
So in this process you made some important contributions to this discipline. What was the effect of this on your international reputation?
In 1956, I was very fortunate to be awarded a Harkness Fellowship—in those days, it was called the Commonwealth Fund Fellowship—which was a wonderful opportunity to go to America for a year. In fact, I was following in old JM’s footsteps because my old professor had held a Harkness Fellowship in his time, when he was a young man. He always told me that it was the most wonderful year of his life. They sent me to the University of Chicago. That, again, was a wonderful choice because there I went to work with a chap called Mark Inghram, who was one of the most wonderful machine builders in the world; and yet, you know, as a professor of physics at Chicago, he’s had no particular recognition.
However, as a graduate student, Mark had worked with Al Nier and Dempster on the Manhattan Project, building these huge mass spectrometers, making the atom bomb. Mark gave me Dempster’s old original lab at the University of Chicago in the physics department. That even had a story connected with it. I thought I’d clean up the new lab I was given and I saw this pile of what looked like old junk on one table, which was a very crudely built magnet and a vacuum system made with bits of brass stuck together with black wax. I’d loaded it on to a trolley to be taken away to the tip, when Mark came in and said, ‘Oh, for God’s sake, don’t do that; that’s Dempster’s original mass spectrometer.’ He said, ‘I’d better take it away from Philistines like you.’ So it was sent off to the Smithsonian.
So this was a very useful experience for you when you came back to Australia.
I should really have told you something about Mark’s machines, because Mark’s machines were a thousand times more sensitive than the machine I had got originally. It had resolutions of one in 4,000, which meant you could go up to much higher molecular weights. It had vacua at 10,000 times better than what we had in our old machines. No more glass and black wax; it was made with argon arc welded inconel and held together with gaskets of pure gold. It was wonderful. We built a machine there in Chicago, using photons to produce our ionisation instead of electrons. That was, again, a thousand times better than anything we’d done before.
Better machines + clever mathematics = clearer data
So, as soon as I got back to Melbourne, in a few months, with a bit of help from CSIRO, I’d built another, better machine. That’s one thing you find out when you build machines: as soon as you build one machine, you know how to build a better one. My machine now had a resolution of one in 5,000. Single ion peaks, like that peak at CO, for example, at mass 28, which used to be just one peak, now you’ve got a triplet of three peaks for it instead. Because carbon monoxide (CO), nitrogen (NO2) and ethylene (C2H4) are all nominally mass 28 but because of the tiny differences in isotopic masses, are not whole numbers.
So you could separate them out.
Yes. I was still trying to get monoenergetic electrons, and here is where I had another idea. I’d become a bit of an electronics man by that time. And there is a principle in electronics called negative feedback, which means that a circuit that you think will do one thing will do exactly the opposite. What the spread in electron energy did was to mess up my curves by smearing them out; so I smeared them even more and then tried to use the principles of negative feedback to cancel this out—and, to my absolute astonishment, it worked.
To unsmear them?
Yes, to unsmear them. It took an enormous calculation. That’s where I had made a friend of an old chap called Professor Eric Hercus, who used to be a professor of physics at Melbourne but by that time had retired and was looking after CSIRAC. CSIRAC was one of the first electronic computers in the world, built by CSIRO. By that time they’d put it in the physics department at Melbourne, and Eric Hercus suggested: ‘Why don’t you try doing your calculations on that?’ He helped me to write the program for CSIRAC, we ran it and, to our astonishment, it worked like a charm and did wonderfully.
This is a very important theoretical contribution to the business, not only building better and better mass spectrometers; you also improved the techniques theoretically.
This technique was called deconvolution. There, again, there’s rather a funny story because an awful lot of people didn’t believe it and they told me that I was trying to break the first and second laws of thermodynamics and all sorts of other sins. But, in fact, the United States Air Force took up the idea to sharpen up pictures of Mars! This technique has turned out to be very successful. These days if you buy a program for improving your photographs called Photoshop, you’ll find that they use deconvolution to improve your images.
International recognition and the dawn of computers
With this advance, another important contribution to mass spectrometry, your international reputation grew and you got some very good offers overseas.
In 1962, I think, in what was really the highlight of my career, I was invited to give a talk about my work at the Solvay Conference. This is a most unusual conference. They’re held in Belgium and they’re convened by the King of Belgium and they’re a gathering of almost all the most important physical chemists in the world. There was I, having to go and give my talk to them. That was, as I say, a marvellous experience for me, to meet all these people.
Then, in 1964, I was invited as a visiting professor at Princeton to continue my work. But, here again, to my surprise, the friend who invited me had gone off to be presidential adviser and I discovered that Princeton didn’t even have a mass spectrometer, even though it was one of the wealthiest universities in the United States. But they did have a marvellous computer, which had all of 32K of memory, which at that time was a tremendous advance. So I did a lot of computation, with some help from experts there, and wrote programs to identify mass spectra. More importantly we wrote a program which allowed you to show where the ions went to, when they went into a mixture of electric and magnetic fields. This developed into our suite called SIMION, which has been very widely used since in the design of mass spectrometers.
So you really were one of the pioneers introducing computational methods into chemistry.
Well, in a way. Nowadays, you can do wonderful things with computers. I should have shown you, when I was using CSIRAC, that was an enormous machine (I forget how many kilowatts of power it used) but nowadays you can buy a little chip for about two dollars which will do the whole job for you.
Yes. CSIRAC, by the way, is now in the Melbourne Museum.
That’s true, but it’s still a wonderful achievement. It’s very tragic that the farmer members of the CSIRO executive decided that there was no future in computing. That’s why they stopped work on computing in Australia. Australia was one of the leaders at the time, back in the late-1950s, 1960s. And yet, to me, nothing that they’ve done in computing has impressed me so much as what Eric Hercus did for me with old CSIRAC. When something that used to take me perhaps six weeks to do suddenly poured out of the machine in 10 seconds; there’s been nothing equivalent to that since.
Did you enjoy the university environment after Princeton?
My family and I loved it at Princeton; it was a beautiful place. We had many job offers in America but there were problems in American life. We talked it over with the family and my wife and I decided that Australia was a far better place to bring up children than America. So we came back. At that time, about 1966 or so, we heard that there was a new university being set up in Melbourne called La Trobe, and I was offered a foundation chair in chemistry. I wanted to get back and see how I’d manage in teaching, so with some regrets I left CSIRO, where I was very happy, and went to La Trobe. That was an eye-opener for me because learning was not the sole purpose of a university; I also got an education in university politics. In CSIRO, we had been a collection of gentlemen; suddenly, when you got into a university environment, it was boots and all. A real eye-opener to me as to what life in the raw was like!
So you had to compete for resources?
Yes, you had to compete for just about everything; but I managed somehow. I had to build up a workshop from scratch—because to me, if you’re a machine builder, you have to have a good workshop. Within a year, we’d managed to get a little workshop established and I’d built another mass spectrometer to get on with my research.
Separating mixtures at La Trobe
How did your research develop in this new environment; what was the next challenge?
We still had this disadvantage. A mass spectrometer is a wonderful instrument, but your samples have to be pure; you can’t put a mixture of things into it. What was, I think, the most wonderful breakthrough in chemistry at that time was the invention by two fellows called Martin and Synge of the gas chromatograph, which was very simple. They got a Nobel Prize for it, but it was an extremely simple device. It was a length of glass tubing about, eight feet (two metres) long, about an eighth of an inch (three millimetres) in diameter and it was filled with dust. Any old dust would do; powdered brick dust would do in the first experiments.
If you put a sample of a mixture at one end of this tube and then started to flow hydrogen gas through it, they discovered that molecules of different molecular weights travelled through this tube at different speeds. So that, at the other end of the pipe, you could collect them one after another as they came out over a period of time. Here again, there’s a rather sad story about Australia. There was a wonderful detector for this, the flame ionisation detector for gas chromatography, invented by a young Australian, called Ian McWilliam, at ICI, who’d had no recognition whatsoever for the work that he did—but it was a wonderful thing.
So the effect of this was that, in a mixed gas sample, the constituents would emerge one after another, separated in time but they still had to be identified.
You still had to collect these samples one by one, as they came out of the end of the pipe, and then put them into your mass spectrometer. And here’s the other problem: as they came out of your pipe or gas chromatograph, they were at atmospheric pressure, whereas the mass spectrometer had to have samples at about a millionth of an atmosphere pressure or less—and how on earth did you convert a sample from one pressure to another?
We spent several years in trying to find ways of joining the outlet pipe of the gas chromatograph on to the inlet of our mass spectrometer. We finally achieved that and this gave us a thing called a GC-MS (Gas Chromatograph – Mass Spectrometer). This was a wonderful device, except that it had another problem, and this was the fact that you now had a flood of information. You see, with a typical mixture when you put it into a gas chromatograph, it might take half an hour for all the various samples to come out one by one and then go into your mass spectrometer. Each one of those samples, produced a mass spectrum of maybe 50 peaks of ion fragments in it, and you had to record all this mass of information. Each peak came out for about 30 seconds, and you’d like to have three or four mass spectra of it, so you had to have a means of scanning through a mass spectrum in about three or four seconds.
You had to speed up the mass spectrometer?
You had to speed up the electronics to make it work fast enough. We scanned by varying the magnetic field and we found ordinary solid iron magnets wouldn’t do it. This was because in a chunk of iron there are things called eddy currents, which slowed down its response. So we developed laminated magnets. We built our magnets out of sheets of thin iron put together to produce a laminate. These, we found, would scan at a rate of perhaps a twosecond scan to get a mass spectrum.
But, then again, the ions were recorded on a pen recorder, and the pen wouldn’t go up and down fast enough to record the peaks in the mass spectrum. To begin with, a run would produce about 200 metres of paper from the pen recorder, with peaks all over it. You’d give that to the organic chemist who’d brought a sample to you for analysis and say, ‘Look, here’s the answer to all your problems. You’ve got to go away and measure up all those peaks, assign a mass scale to them and then you’ve got to interpret those mass spectra.’ Well, of course, we wouldn’t see him again for a couple of years, with luck.
Really, the whole job is much more suited to computers to sort out this data!
It was very obvious that, with this flood of information, it wasn’t going to work to do it that way. Up till then, the only way you could communicate with computers was by means of a typewriter or a Flexowriter and results came back on sheets of computer paper. But then Digital produced a new kind of computer called a PDP8 that allowed you to get voltages out of your computer instead. So you could tell it to scan a voltage and instead of numbers, a time dependent voltage would come out. I was very lucky: the Australian Research Grants Committee gave me a small computer and, with that, we first of all managed to make it control our magnet sweep; then we got it to record the ion peaks and measure up their heights; and then it assigned a mass scale to them and wrote it all into memory.
But that still presented us with a problem, because now you’ve got, say, 50 mass spectra for each substance and you’ve maybe got 200 or 300 samples in your run of a mixture, so you’ve still got an enormous amount of data. What could we do to interpret the data? Whilst I was at Princeton, I’d been writing programs to interpret or at least recognise a mass spectrum. By that time, mass spectrometrists all over the world had gathered mass spectrum information for about 20,000 molecules. So we had a catalogue of mass spectra and we managed to put this all on to a disc of the computer. We then found, if a new unknown was fed to it, it would run a pattern recognition program and, in 10 seconds, you could scan 20,000 mass spectra and identify one—if it was there in the catalogue.
So what we’re seeing here is the beginnings of GC-MS, the combination of a gas chromatograph and a mass spectrometer, one of the most important analytical tools that you helped develop.
Yes; but I haven’t told you the whole story about this computer and its uses. We still had the unknowns, those molecules that the mass spectrometer had never seen before. What do you do with them? This is when we got an idea! If you look at a mass spectrum of CO2, for example, you’ll see that there’s a peak at 44, which is the molecule, there’s one at 28, for CO, there’s one at 16 for oxygen and then there’s carbon at 12. Any mass spectrometrist who looked at that would say, ‘Aha, CO2.’ But can you write down a computer program that, if the computer saw that mass spectrum, would also say, ‘Aha, CO2’ or ‘NO2’ or whatever the molecule happened to be?
So you’ve got to teach it human skills.
We managed to write some artificial intelligence programs that would take a completely unknown spectrum and tell us, within a matter of five seconds, everything that it could figure out about it. We were surprisingly successful with that; it worked quite well.
And what about new developments in mass spectrometry?
Yes, there was another great discovery. A German, Professor Paul, discovered a kind of mass spectrometer called a quadrupole, which was an extremely simple instrument. When I saw one for the first time, I went back home to my lab and in two weeks I’d built one for myself out of brass in the workshop. With a quadrupole, you could scan a mass spectrum 50 times a second, which was a tremendous improvement. It wasn’t as good at resolution as the magnetic machines; but, nevertheless, for a lot of purposes, it was perfectly adequate. We must have built 30 or 40 quadrupole mass spectrometers in the lab, they were so easy to build.
And they worked much faster. But they worked by a different principle: not magnetic separation, but ion frequencies.
It’s that you put an alternating voltage on the ions, they then vibrate back and forth and, depending on their frequency, the heavy ions move more slowly than the light ones. So, that’s the principle on which this machine works—and it works very well.
During the time when all this interesting research was going on and all these marvellous results came out, La Trobe University, like all other universities, was in a very turbulent state with all the student riots and dope smoking—a very difficult environment. Can you tell us a bit about how you survived that?
I was lucky because, when you’re working with science students, they tend to be much more conventional people—old-fashioned in their attitudes, you might say. It was mainly the humanities and sociology students with which we had most of our problems.
David Myers, the vice-chancellor at La Trobe, asked me to design a university college for them and then to be its master and live in it for six years. So we had quite an experience. You see, HG Wells had always said that science would save the world; but having to deal with a population of something like 360 people in the 18-to-21 year age group gave me a different story of what saving the world was going to be like.
But you survived all right.
Yes, we managed it, although I must say that it was a blessed relief when I was invited for a while to go to stay at the University of Utah.
You’d been there before, I think, during an earlier visit, so you were a known quantity in the business.
Yes. You see, there had been a very famous mass spectrometrist at Utah, Henry Eyring, and I must have made a good impression on Henry because they used to invite me back almost every year to Utah and I had made many friends there. This turned out to me to be one of the happiest chemistry departments in the world—and I don’t know why, but I always liked Utah very much. It was a blessed relief to get away from our student problems to the much more conventional students of Utah, with the Mormons.
Christine and I had always been rockhounds and Utah is a rockhounds’ paradise. I had been very lucky to make friends with an old prospector that I met in the deserts north of Salt Lake City, and he used to take me dinosaur hunting up into the San Rafael Swell, near Capitol Reef. All of the most elegant dinosaurs lived in what was called the Morrison Formation, which intrigued this fellow very much. It wasn’t me; it was another Morrison, an itinerant geologist, that used to wander through those parts—but, just the same, I got some of the credit for it with him.
And you picked up some marvellous samples of dinosaurs. I saw some at your place: dinosaur bones and fossils.
That’s quite true. I got very interested in dinosaur bones generally. This is a slice of a dinosaur’s leg bone, I think they used to call them brontosauruses; I don’t think they call them that now. You’ll see that there’s all the cell structure of the bone there. This is one of the vertebrae of the tail of a small dinosaur and, if you cut through the middle of this with a diamond saw, you’ll find that there’s a reddish deposit. I got very intrigued by this red. I thought, ‘Could it be dinosaur’s blood—some remnant of it?’ So I thought I’d get some samples. Using a clean diamond saw, I cut through one of these bones, took this sample and put it in the mass spectrometer, and I looked for haemoglobin—well, I looked for heme, one of the deposits of haemoglobin. I didn’t find haemoglobin, but I did find porphyrins, which are another molecule of life. So it was interesting that there are still some residues of the organic material in a bone which is, say, 200 million years old.
You were strongly tempted to stay in Utah but, nevertheless, you returned to Australia.
We liked Utah very much; in fact, I’ve held a honorary professorship there ever since and taught there frequently. But I still felt that Australia gave me all the chances in my life and I think we felt we owed Australia a great deal because of that.
You came back and continued your research in both aspects: the building of better and bigger mass spectrometers, or higher resolution mass spectrometers, and also the computational aspect of the work.
That has rather a funny story connected with it. You see, dating from my X-ray crystallographic days, I’d always dreamed of being able to determine the structure of a gaseous ion. It’s much more difficult than with a crystal, because you’ve got molecules sitting in space with a charge on them. So I got the idea of building a new mass spectrometer of three quadrupole mass spectrometers in a row, one after another—one to separate out one species of molecule ion and one to irradiate the ions with light from a tuneable laser, and then a third mass spectrometer to examine if there were any products. We did manage to get a spectrum and to produce a set of the bond lengths and bond angles, which was very nice. But, to my astonishment, we also discovered that we’d invented a new kind of mass spectrometer: the so-called Triple Quad, which allows you to produce two-dimensional mass spectra. In fact, this machine has found a lot more use recently detecting drug use by athletes.
And it’s all over the world!
But now let’s just get back to the GC-MS, the gas chromatograph mass spectrometer system, and the business of odours, which formed a large part of your applied science work apart from all these theoretical computational developments. Let’s talk a bit about the detection of odours; give us some examples or tell us more about that aspect of your research.
I should first say something about the sensitivity—why GC-MS is so good for odours. It’s a wonderful analytical tool—the GC-MS-computer combined. You can analyse very complicated mixtures with enormous sensitivity. If you see a beam of sunlight in a darkened room, you’ll see tiny little motes of sun light. That is these little tiny particles of dust which reflect the sunlight, which is how you see the beam of light. These particles would weigh about 100 millionth of a gram. And we are able to analyse something 100 million times even smaller than that: about a 10-16 of a gram of sample. Now, even then, it’s still 100,000 molecules, but it’s pretty good. This makes it particularly good for analysis of odours, where you’re looking for extremely low concentrations of chemicals.
I got fascinated by odour because your eyes are a message to your intellect but odour is a chemical message to your emotions. Odour can convey all sorts of messages to you. It can tell you of home, pleasure, food, appetite, decay, illness, warning, even fear. It’s also a fantastic trigger to memory. I remember going back to Broughty Ferry, where I’d been as a child, and suddenly recognising the smell of the North Sea, which is quite different to that of any other ocean in the world. And everybody loves the odour of flowers. Women in particular have always appreciated the odour of perfumes; and, I think the reason they wear perfumes is because perfumes are such triggers to memory. I can remember my mother and the kind of perfume she used to use. My wife had Chanel No. 5, which always reminds me of her when I smell that particular perfume. My mother-in-law had Fleurs de Roccailles.
So you’re saying that the GC-MS computer system is really an artificial nose?
The average human can only distinguish about 800 odours; a good chemist can distinguish about 20,000 different odours; and with the gas chromatograph mass spectrometer, you’re very much better off. The average human is not particularly good. The maximum sensitivity to odour, I think, is due to the smell of old football socks, which is isovaleric acid, which people can smell at a lower concentration than just about anything else. But, by comparison with a good dog…. a good dog can follow a trail laid by a man wearing three-millimetre thick rubber gumboots and follow it along the ground. Even that fades into insignificance when you compare it with salmon, who can find their way back to the stream where they were hatched from an egg—to go, in turn, to lay their eggs. Eels find their way back to the Sargasso Sea by a particular chemical mixture. Of course, you can hardly say an eel or a salmon is smelling—they do it through their skin—but it is the same sensation of chemical detection. And sex pheromones in insects, a good male moth can detect a lady moth five miles downwind, from the tiny amount of chemical that she liberates.
Cardboard flavoured milk, cucumber smelling fish, the odour of fear…
It must have provided you with some interesting applied problems.
There was the dairy division; Geoff Loftus Hills ran that at that time. The dairy division were having a lot of trouble with a cardboard flavour in milk, which they thought was due to the fact that the milk bottles were stoppered with a little disc of cardboard at the top. At a lot of expense, they changed over to an aluminium top, but they still got a cardboard flavour. By examining it with the GC-MS, we found that it wasn’t due to cardboard at all; it was the effect of sunlight through the clear glass bottles that was producing the molecules that produced the cardboard flavour. Of course, you now can buy milk in cardboard cartons and there’s no trace of cardboard whatsoever; that’s because it keeps the sunlight out.
What about the fish?
That’s another story. A young zoologist came to see me. He’d been looking for a fish that was thought to be extinct, the Eastern Grayling that used to live in the Tambo River—and it was known to the locals as the so-called ‘cucumber fish’. He said, ‘Could we see what this is?’ He caught one and brought it back to the lab. We examined it in the GC-MS—not a trace of any smell that was anything like cucumbers. So we said, ‘What can be wrong?” We sent him back to the Tambo River again, this time with a small dewar of liquid nitrogen.’ He caught us an Eastern Grayling, popped it into the liquid nitrogen and brought that back to the lab. We then put it into our GC-MS and, to our great delight, we found a molecule which turned out to be exactly the same molecule that is the odour of long cucumbers. Tim went back to the stream and put some of this chemical in the stream—and, to his great surprise, he found that it frightened the other fish. We think it was a defence secretion: when one fish was injured, it liberated this chemical for a very short time, which frightened all the other fish away. This was a smell of fear.
This led me to another problem that had always intrigued me. How students, just before exams, would get into a state of panic, they had this phenomenon of fear. Horses, dogs and bees can detect if a person is afraid, and it seems to be infectious: if one person is afraid, somehow other people very rapidly become afraid also. This is the phenomenon of panic, and I spent a lot of time with the GC-MS looking for the odour of fear. Think of what a wonderful war weapon it would be, if you had the smell of fear. But so far we haven’t been successful and that’s something for the younger mass spectrometrists to get on with and do.
But, apart from these fun problems, there were some industrially important ones; right?
Some of those were quite good for us in the lab. One firm in Australia was trying to make a fat-free cheddar cheese, so we spent a lot of time investigating various sample batches of their cheese. We finally came to the conclusion that the fat was an essential part of making the flavour of a cheddar cheese; but the good thing was that it meant the whole lab was eating cheese for quite a while. Another problem was an analysis of the bouquet of wines. It’s only a few milligrams of chemical that makes all the difference between a Hermitage Grange and what’s known commonly as ‘plonk’. If you could find out what the right chemicals were and add them to a sample of poor wine, you could make it a very expensive one.
Another food firm wanted to find out why food doesn’t taste as good nowadays as it used to, and they were trying to make an old-fashioned fishcake. We put the fishcakes into the front end of our GC-MS, ran the gas over them into the gas chromatograph mass spectrometer. We found that there was a difference between the fishcakes they were making today and those of old-times (which an old lady had prepared). And there’s a very simple answer: in the old days the fish, when caught in the North Sea, were stuck into the hold and it took them two or three days to get back to land. Nowadays they’re popped into a freezer the minute they’re pulled out of the water—and it’s the bacterial action of decay in the fish over a two- or threeday period that produces those wonderful flavours. As with so many foodstuffs, the important flavours are produced by yeasts or bacterial action—and, with the GC-MS, it’s duck soup to analyse them and find out what the flavour was and why it’s no longer there.
I’ve also heard about your work in identifying the smell of things which are not supposed to have a smell, like rocks or metals.
Yes. With an awful lot of things, you wouldn’t think they had a smell; and yet, a woman I knew in CSIRO, Isabel (Joy) Bear, was working on the smell of wet rocks. Anybody who goes walking in the countryside can tell you that, if they’re in limestone country, they can smell the rocks. When the rain falls on a country road in Australia, an odour arises from the road which is quite distinctive; once smelled, you will never forget it. We were able to take the sample of wet rocks and find that every kind of rock has a different odour which your nose can detect.
In the case of money, that was rather amusing. I got talking to a little fellow called Nugget Coombs, who was at that time something to do with the Treasury. He had a forger who was making forged 10-dollar bills, and he said, ‘Can you smell the difference between a forged 10-dollar bill and a real one?’ Well, we put a 10-dollar bill into the GC-MS and, sure enough, we could detect different molecules there. I think it was the dye interacting with the paper that was doing it. But, as it turned out, they caught the fellow who was making the forged bills, so we didn’t manage to put a mass spectrometer into every bank.
But there was also an application which was to do with fossils and the dating of fossils, which is an unusual application of mass spectrometry. Could you tell us a bit about that?
That’s another old friend, called Edmund Gill, at the Museum of Victoria; I have acquired a lot of friends through looking at different problems. In the 1950s, Harold Urey, a wellknown American chemist, had shown that the ratio of oxygen-16 to oxygen-18 isotopes in ocean water is pretty constant—about one part in 250 for the 18O. What Harold Urey had shown further was that a shellfish, when it grows in ocean water, locks up the ratio of the isotopes at the time that it grows and careful measurement of this will tell you the temperature of the water in which the oyster lived. So Edmund came along with a whole sample of fossil oysters going back for the last 40 million years, and we put them into our mass spectrometer and examined the oxygen 18O : 16O ratio. To Edmund’s great delight, we discovered that, for the last million years, temperatures were pretty much what they are now in the south of Victoria; before that, they were a little bit warmer; but then, 20 million years ago, temperatures were five degrees warmer. It turns out that was the period of the Oligocene or Miocene, when the brown coal beds were laid down with tropical forests. So it seemed to fit—this finding that ocean temperatures were quite a lot warmer at that time.
That led us to another problem. I had a young archaeologist that came to do a PhD with me on Aboriginal shell middens. As you know, a shell midden consists of a little pile of shells. The Aboriginal women went into the water to gather shell fish and then they lit a campfire. So what you find is a little trace of charcoal from the fire and the shells of the things they’d eaten. Michael [the PhD student] took these samples of shells from shell middens. As you go deeper into the midden, you go back in time. The carbon gave us a date for how long ago that fire had been lit, whilst the shell told us not only the temperature of the water—but, when you look at the isotope ratio from the growing edge of the shell, you could tell that every single shell in the midden had died and been eaten at the end of winter or beginning of early spring, all through those 40,000 years. It was fascinating that you could do that with mass spectrometry.
Aboriginal pharmacopoeia project and Byzantine coins
There was another fascinating application to do with plants used medically by Aborigines.
Ah, yes. Well, this arose from the fact that the government sent me, in the early 1980s, to China to see what the Chinese were doing with their herbal medicine. I think knowing of my interest in herbs was the reason they sent me and I took with me a small group. To our great surprise, we found that the Chinese were using mass spectrometers, which they’d been given, to examine their herbal medicine. One of the members of my party was Ella Stack, who had been in charge of Aboriginal medicine. It was Ella’s suggestion to say, ‘Why don’t we do a survey of what herbs the Aborigines have been using for 5,000 years and see if we can find out what chemicals are there?’ This started the Aboriginal Pharmacopoeia project, which, it turned out, the Aborigines in the Northern Territory took up enthusiastically. We got swamped with loads of samples of plant material from all over the Northern Territory and we did find some rather interesting chemicals in these and produced a book on the pharmacopoeia.
Give us an example of a chemical or an application of these chemicals.
There was one plant from the Centre and when they were fishing, they’d put the leaves of this plant in the water and all the fish would come up to the surface, unconscious, and they could be gathered up. It was also used for toothache, as they found it was an excellent substance.
What about the analysis of ancient coins?
I collect ancient coins and I got the bright idea: what if we could analyse a coin and see what sort of mixture of metals were there; we could work out where they got that metal from? There’s a new kind of mass spectrometer called laser ablation ICP-MS, which blasts a laser at a coin; you produce a tiny little crater, which is so small you can hardly see it. But all the metals in the coin are vaporised and go into the mass spectrometer to produce a mass spectrum.
To our surprise, we found nearly every element in the periodic table in the coin; they obviously weren’t very good metallurgists. I’d hoped to be able to show from which mine the metal had come; but, unfortunately, I found that with Byzantine coins, that are from about 700 AD, there was such a mixture in various coins that they must have scrounged any old metal they could get. Even in a bronze coin, there were measurable amounts of silver and gold.
In building all these mass spectrometers you must have had some pretty good workshop people involved.
Yes. That’s something I would like to say: I owe just about everything I’ve done in my life to the men in the workshop, who’ve turned ideas into machines. I’d like to mention Mr Colberg—I never knew his first name—at the University of Chicago; Sid Powell, Jock Mills, Dai Davies and Fred Box at CSIRO; and John Chippendale, Don Balaam, Daryl Huntington at La Trobe. You don’t need millions of dollars; you just need a good workshop. As I said before, the minute you build a good machine, you’d know how to build an even better one. The great discoveries of the future are going to come just from somebody seeing something odd and being curious about it. It helps, of course, if you’re good with your hands, if you know how to use a soldering iron and if you’re a good scrounger. The complicated electronics that we took so much trouble to build you can now buy for a few cents as silicon chips. The only other piece of advice I would give is: don’t pay too much attention to theoreticians who tell you that you can’t do it.
And what about the difference between the CSIRO and universities in the fact that you have research students?
That was rather interesting. CSIRO, as I said, was all fairly senior scientists or who became fairly senior, but you had very little in the way of assistants. You just had to do everything yourself, if you wanted something done in the lab. Then, when you go to a university, you’ll find a supply of graduate students that are pairs of hands that will help. Slowly, I think, the trend has been away from CSIRO into the universities, at the present time. But, nevertheless, it has been a very happy time for me, just the same.
Now, one final question: a lot of what you’ve described is really experimental physics applied to chemistry. Now, what are you really: are you a physicist or a chemist?
I wouldn’t worry too much about what you are. I think the vision of Ian Wark and Lloyd Rees in setting up the CSIRO Division of Chemical Physics, where they explored the application of modern physics to the problems of chemistry, was tremendously successful. As I say, it worked out not one of us cared whether it was physics or chemistry; you just had problems and solved them—and I think that was Ian Wark’s philosophy very much, and we all admired him for it. Nowadays, chemistry is moving into biology and also into physical methods.
I should have mentioned earlier that, up till about 1983 or so, you could never examine a molecule in a mass spectrometer at more than mass 3,000. But then a man, who was 70 years old at the time, made a remarkable discovery; what’s called electrospray ionisation. It is a new method of ionisation, which lets you ionise molecules up to a molecular weight of 10 million. This meant that, combining his source with our Triple Quad, we were able to study RNA and DNA, the molecules of life.
Even whole viruses.
Yes. There’s been a discovery made just a few years ago, which I’m very surprised more attention hasn’t been paid to, and that is molecules in space. What these young folk did was to take a sample of Tobacco Mosaic Virus, put it into an electrospray source, ionise it, then put it into the mass analyser at high vacuum, accelerate it with high voltage, collect it on a collector plate and then prove that it was still living and able to reproduce as a virus. Many years ago, there was a Swedish chemist, Arrhenius, who said that maybe life started on earth from spores that had come from outer space; and everybody said, ‘Oh, don’t be ridiculous; life couldn’t survive in space’! Here they have proved with this electrospray source that, yes, it can. So who knows?
So there are all these fantastic ramifications from what started out as a simple question of what can you do with a mass spectrometer?
Yes, I think, there’s no doubt that you can do quite a lot with mass spectrometry.
Well, thank you very much indeed, Jim, for sharing with us the story of such a brilliant career in science. Your innate modesty has prevented you from mentioning that you were elected a Fellow of the Australian Academy of Science as long ago as 1964 and a Fellow of the Royal Society of Edinburgh—the national academy of Scotland—and you were appointed an Officer of the Order of Australia in 1990. So a brilliant career indeed. Thank you very much for talking to us.
Thank you very much, Tony.
© 2023 Australian Academy of Science