Professor Sir John Enderby FRS (1931-2021): a personal reflection

Shortly before I retired fully from my three decades as an academic at The University of Kent I wrote a short series of blog posts on aspects of my career (starting here). They were drafted in a bit of a hurry in response to a request from one of my colleagues – who was, it transpired, already contemplating a ‘retirement conference’ in my honour and wanted a little biographical material; they were far from exhaustive. Within that handful of posts there is mention of the person who kick-started my career in science in the mid-1970s and who influenced it from time to time for the next thirty five years or so …

When I first came across John Enderby he was ‘Professor Enderby’ and the head of the Department of Physics at the University of Leicester, where I was an undergraduate student. It was years later that he became a Fellow of the Royal Society and was subsequently knighted. Sadly, John died at the beginning of August in 2021; he was 90 years old. Only now, a year later and after the worst of the COVID-related restrictions and fears are in the past, was it practicable to hold a meeting to celebrate his considerable contributions to science. As one of the few people still around who had worked with him during his time at Leicester (and for whom the organisers had contact details) I was asked to contribute to the short talks planned for the first day of the celebratory meeting. It was an honour to accept the invitation. This blog post is, in essence, the distillate of my talk on September 5th at ‘Understanding the Structure of Liquids: Celebrating John Enderby’s Scientific Legacy’ at The University of Bristol.

Family members, friends and former colleagues as photographed at the end of the meeting’s first day by Adrian Barnes. (Should you wish to know, when this was taken I happened to be sitting third row back, second from the right; the image shown below is of the period I was speaking about in my talk.)

An immediate difficulty faced when putting together my slides arose from the lack of contemporary images: the key events took place well before the advent of digital photography or scanners. Photographs were something of a rarity, doubly so in the case of colour. Add to that the fact that I’d been ruthless in clearing out my office as I approached retirement ... I did however find a scanned copy of the above image, taken at a Research Council Graduate School held at Leicester in 1977. John is sitting front left and a very young me stands centre-rear. There are so many distinguished scientists of the time shown in this image, and quite a few early-career people who went on to build amazing careers of their own. (When I first located this image, I confess that one of my initial reactions was to lament the lack of diversity – a situation too often ignored at the time I regret to say.)

In truth, I can’t say I remember anything specific of John until the end of my second year as a naïve BSc Physics student*. I had requested a final year research project in the area of Solid State Physics – an area that had increasingly fascinated me during that year, probably due to some inspirational lecturers – but I honestly couldn’t recount my decision-making process now (even to myself). My project partner and I found ourselves tasked with the study of manganese chloride aqueous salt solutions using Electron Spin Resonance, a technique traditionally rooted within the realm of Chemistry. Could this really be a suitable project in Physics? Our project supervisor was to be none other than Professor Enderby, which was a scary prospect. (I discovered years later that the project’s inception owed much to a conversation that John had had with his research associate George Neilson, whose background was in Chemistry.) This was my first proper exposure to what would eventually shape my own research interests across four decades: the belief that so much of interest lies at the interface between our traditional subject disciplines. For that alone I owe John a huge debt of thanks.

Central to the images above is a monochrome image of the ESR spectrometer we used for our allocated final year research project. It was taken by the departmental technician who acted as official photographer. I was given a copy, as was my project partner, which I annotated by hand and included in my project report – the front cover of which is reproduced on the left. The report itself was typed using a fairly basic typewriter; the equations were inserted by hand as were all graphs, diagrams and tables. I generated a carbon copy for myself; there were no photocopiers in the department. Very few people possessed an electronic calculator at the time, which were still fairly primitive back then – and prohibitively expensive, so calculations were undertaken using logarithms and slide rules.

Unbelievably to us at the time, my project partner and I were invited to a party at John Enderby’s house to celebrate his research group’s success in winning their first truly substantial research grant from what was then the UK Science Research Council. Being made to feel welcome – a part of the team despite our particularly junior status – had a great impact; it afforded one of the many lessons I have sought never to forget. However, there were things to learn from the day-to-day as well. For instance, John’s habit of wandering through the labs. most days, coffee cup in hand, is one deceptively simple example. He’d engage anyone and everyone in conversation about what they were doing; keeping himself abreast of developments of course but, in the process, bolstering the confidence of undergraduate and early-career researchers alike … whilst also keeping them on their toes. With my time as an undergraduate student coming to a close I began the process of sorting out what my next step might be. I had obtained a place on a PGCE course, so secondary school teaching was one attractive option. However, despite enduring feelings of inadequacy, my ambitions were focused on the desire to dive into research. Thus, despite fascinating offers in the areas of ionospheric physics and geophysics, it took me relatively little time to accept John’s offer to join his group as a PhD student.

John’s own 1963 PhD thesis was entitled ‘Some electrical properties of liquid metals’ – my own, submitted sixteen years later wasn’t that dissimilar, although the theoretical landscape had altered considerably in the intervening period. The computational equipment available had progressed a great deal by the time my PhD project came to an end, but the project itself was conducted on a shoestring budget.

"Liquid metals" implies high temperatures – up to about 1750°C in my case – but without much of a budget everything had to be built by hand. Simple angle-iron frames held furnace bricks stacked within an asbestos box (- yes: I had to cut and drill such sheets, the work being done outdoors and using water to suppress dust; different times). The furnaces were lowered/raised using simple screw jacks and the basic vacuum system included copper tubing soldered together by me; I also did all the glass-blowing and the machining of many other components. The colour inset is one of my wife’s still life paintings: a jar like this was used as my primary calibration cell – the whole project rested upon its use!

As it turned out, after a period of study leave in the USA, John left Leicester for a post in Bristol only a year after my PhD began so I never did benefit from his continued day-to-day supervision. One of his Leicester colleagues, Alan Howe, bravely took me on and became my key early-career mentor in John’s stead. John and I stayed in touch however and met on innumerable occasions through the years. This included the period of his tenure as Physical Secretary and Vice-President for The Royal Society, during which time I recall being treated to an excellent meal at the Army & Navy Club so that he could debrief me on my department’s performance in the recent Research Assessment Exercise. I’ve lost count of the number of supportive references etc. he wrote for me, and I have cause to be particularly grateful for his gentle nudges into what became an extensive involvement with the UK Research Councils (see here).

During the first couple of years after the move to Bristol in 1976 John would visit his old department at Leicester often. On just such a visit he wandered into my small lab. for a chat. I wasn’t there, so he had to make do with my latest written log entries. At this point I ought to point out that John was incredibly enthusiastic when ostensibly exciting results emerged, but occasionally this enthusiasm misfired. In the longer term it was never a problem: as the saying goes, first attributed to Nobel Laureate Linus Pauling, “The best way to have a good idea is to have lots of ideas and throw away the bad ones.” John was a master of this approach, which I heartily applaud, but in the short term there are risks. He thought that my data on the resistivity of liquid palladium-silver alloys might represent the first evidence for ‘paramagnons’ in a liquid metal and he duly shared this idea widely. It didn’t, as I demonstrated through further measurement in the months that followed. No long-term harm was done; John was an excellent scientist: when I had generated more reliable data we simply moved on – that’s how science works.

The above are scanned copies of my PhD laboratory logbook pages, the graph on the left and the lower insert being the ones John saw during his unannounced flying visit. It would have been tempting to take this unexpected ‘spike’ in the graph at 33% Ag at face value. However, scientific scepticism – major claims need major evidence – and the desire for both explanation and reproducibility drove me to track down the origin of the feature. My ‘family tree’ of samples (central panel) showed that the ‘paramagnon-like’ feature was evidently associated with a single sample that had been contaminated by the tungsten electrodes I used. This sample, in its turn, contaminated subsequent samples made from it. Given my vanishingly small budget, I had to wait six months before I could buy fresh samples of high purity palladium and silver in order to measure this region of composition again. The graph on the right, although still fascinating in the context of the theories of the time, clearly shows that John’s paramagnons were, sadly, a will-o'-the-wisp.

There were rather few ways in which I could honour John’s scientific contributions, but in 2006 I nominated him for an honorary doctorate at my own university (Kent at Canterbury) which he was able to receive during a formal university degree ceremony. In 2014 I wrote a two-page article in the monthly magazine ‘Laboratory News’ in a short series on heroes of British science – it gave me my penultimate opportunity to pay tribute.

I hope I possess sufficient wisdom to choose to learn from others: to learn what works and what ought to be avoided. I learnt a great deal from John. Indeed, from my days as an undergraduate student, through various transitory research posts and to my thirty years as an academic with my own thoroughly interdisciplinary research team, John remained a person to learn from. I am thankful for the privilege of having known him.

* I had applied for a Joint Honours degree in Physics & Chemistry, but due to an ‘administrative oversight’ I arrived at Leicester to find myself registered for their BSc Physics programme. Lacking the self-confidence to anything other, I simply ‘went with the flow’. I have used the term serendipity often in relation to my career: this apparently random event is perhaps an early example.