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Ken Johnson memorial address

An address given at the Memorial Service for Professor Kenneth Johnson.

Professor Ian White, Master of Jesus College and van Eck Professor of Engineering in the University of Cambridge
7 October 2015 in the
Chapel of Jesus College Cambridge

It is my privilege today to pay tribute to Professor Kenneth Johnson, and also to read a tribute by Professor Roderick Smith who would have given this address today but sadly is unable to do so in person.

We are gathered here to mark the life of a truly great and fine man, a man whose influence was very special and which extended to many people from a wide range of backgrounds and interests. His contributions and achievements are not solely now matters of record, but are also lived out in the lives of those who were privileged to know him and the advances that have resulted from his discoveries.

Foremost among those sensing Professor Johnson’s loss today are his widow Dorothy, his children Marion, Hilary and Andrew and other members of his family to whom of course he was devoted and who in response gave such love and generous support. That generosity also extended to many of his students and colleagues for whom the Johnson home was a special and not infrequently visited place. Our sincere condolences do go to his family today.

Professor Kenneth Johnson was an academic who made outstanding contributions to tribology, the study of friction, lubrication and wear, with a particular focus on contact mechanics. Those who knew him first and foremost through his research will think of his discovery of the spin effect in rolling contact. Professor Johnson’s work was recognised as being particularly characterised by elegant experiments, skilful analyses and insightful explanations of observed phenomena. His ability however went beyond that, and indeed his work developed in areas well beyond the early centimetre and metre scales of studies such as in railway wheels and rails. At the time of his retirement in the early 90s for example when microprobe instruments such as the Atomic Force Microscope and the Surface Force Apparatus were being developed in physics departments, he was invited to become involved in the study of friction on the atomic scale, where molecular adhesion between the surfaces becomes a major effect. As he has written, this meant that he had to make friends with physicists, for whom friction had suddenly become a fashionable subject. They picked up a paper written a long time previously in 1971 on adhesion in Hertz contacts. This had been written with two graduate students: Kevin Kendall and Alan Roberts and so then suddenly became famous as the 'JKR theory', an excellent name it was joked given the prominence of J.K.Rowling.

For those outside Professor Johnson’s research field, but based within the department of Engineering, there was a great awareness of his commitment to his department not only through research but also in relation both to teaching and his care for the staff and students with whom he worked. He was present in Cambridge over a period of great change for the Engineering department, a department which in the early days would find some in the University questioning the quality of its activities and members, and with it being treated administratively as part of the Physical Sciences. Its change to become the department it is has in part been due to the commitment of members such as Professor Johnson.

For those in this College, there is no question that Professor Johnson was an outstanding Fellow, having been admitted in 1957, and serving faithful terms as Director of Studies, Tutor for Graduates and President. He was devoted to the College and involved in key decisions, in particular the appointment of Sir Alan Cotterill as Master, which in turn was to lead to the College admitting women.

His teaching within College meant much to those of us who had the privilege of learning from him, and indeed attracted prospective students. For example, it was in part due to Professor Johnson that I applied to Jesus College as he, with Stan Evans, had been strongly recommended by Norman Fleck an old family friend. Norman had gone to Jesus College the year before I did, and of course remains in Cambridge now as a Professor of Materials Engineering.

Along with Stan Evans therefore, Professor Johnson was the first Engineering Fellow I met and I still recall learning at interview about how little I knew of both aerial photography and the operation of London Underground ticketing machines. Professor Johnson also supervised me during my first year as an undergraduate, in a manner that I appreciate and indeed cherish to this day. His rigorous approach to analysis, coupled with a very real appreciation for the importance of understanding physical principles and real engineering issues, alongside his kindness, taught me key aspects of my engineering education. He was careful and thorough - seeking deeper understanding of problems, and I was always so grateful for his insights gained from his fascinating research experience which would not infrequently arise at supervision … or at the sherry afterwards if you were fortunate enough to have the last supervision slot before formal hall. However he was more than that, and as Norman recently wrote Professor Johnson really was a father-figure, colleague and friend … . He was an inspiring Teacher and Researcher, with the hallmarks of integrity and quality. These are sentiments which I have seen expressed repeatedly over the last week in messages from past students.

Indeed as I have alluded to, it was another of his mentees, Roderick Smith, who would have been speaking here today were it not to be that he has unavoidably to be in Japan. Now Royal Academy of Engineering Network Rail Research Professor at Imperial College, Past Chief Scientific Advisor to the Department of Transport and President of the Institution of Mechanical Engineers, Rod has written this tribute:

When the Master reads this, it will be sometime after 10 pm in Tokyo where my wife and I will be thinking about the privilege we have enjoyed in becoming close friends of Ken and his family. We regret deeply we are unable to join this service, but we will be with you in mind and spirit, will follow the order of service, and listen to, at least some of, the music.

Born in 1925, Kenneth Langstreth Johnson was raised in Barrow-in-Furness, an industrial port town, then in Lancashire, now Cumbria, famed for the making of iron and steel and ship building. In due course he became a pupil at Barrow Grammar School where his father, a Cambridge Exhibitioner from Lancaster Royal Grammar School, spent nearly all his teaching career. Ken set out on an academic trajectory aimed for Cambridge, but also led an active life of rugby, athletics, Boy Scouting and later mountain climbing on the west Cumbrian Fells.

His second sixth form year of 1941, coincided with the wartime bombing of Barrow, an obviously strategic military target. In normal circumstances he would have stayed at school for a Cambridge Scholarship year. However, the wartime need for technically qualified staff was pressing, so on taking his Advanced School Certificate he became a “Snowflake”: this as he was interviewed by C P Snow then Director of Technical Personnel at the Ministry of Labour and offered a State Scholarship on an accelerated course to read Mechanical Engineering at Manchester. Forgoing his Cambridge ambitions, Ken went to Manchester and after 2 years and 3 months, he graduated with a First and was sent to Rotol in the Gloucester area, a company making propellers for wartime aircraft production. He later recalled that the introduction of a five bladed propeller for the later versions of the Spitfire helped him to equitably divide the pie when his immediate family numbered five. It was to be 1949 before he ventured north again back to Manchester as an Assistant Lecturer in Engineering, having by now met and courted, using the now old fashioned term, his wife to be Dorothy (Watkins) during healthy and wholesome outdoor pursuits such as walking, cycling and Youth Hostelling.

His work at Manchester included a part-time PhD in which he developed his ideas of vibration damping in propeller assemblies by investigating the effects of micro-slip at the interface of joints. Thus began his lifetime devotion to the study of contact mechanics. The outdoors and Scouting flourished, as did choral singing. Ken auditioned for, and was accepted as a member of, the Hallé Choir. During the Festival of Britain year of 1951, he toured the country with the Hallé under Barbirolli, and sang at the re-opening concert at the Free Trade Hall in Manchester, refurbished after extensive wartime bomb damage.

In September 1954, Ken and Dorothy married, honeymooned on the Cardigan Coast and then packed to journey to Cambridge where Ken had been appointed a Demonstrator in Engineering from 1 October. One feels that this move achieved Ken’s long-time ambition: he took to Cambridge and remained here for the rest of his long career.

Following his election to a fellowship in 1957, he became a Professorial Fellow in 1977 and Emeritus Fellow in 1992. He has had a most distinguished career as an academic engineer, although he has contributed to the solutions of many practical and earthy problems, for example in railways and bearings. He has received many of the highest accolades, and received them in an extremely modest manner. I have heard no one speak ill of him, and for my own part have always received sage guidance and advice, for which I have the utmost respect and give great thanks. I leave it to others and other occasions to describe in detail his formidable academic achievements, but note that he had published, by the standards of today, relatively few papers, but papers of the highest quality. Not for Ken the academic buzz words of today, entrepreneurship, huge research teams, mega grants, spin-offs and publicity. He espoused the gentler and nobler characteristics of scholarship, integrity, deep thought and the highest of intellectual standards in research. He took teaching very seriously and not once did I hear him refer to his teaching as “a load”. He was a model for us all to try to emulate; few if any could, but trying made us much better. Typically, on hearing the news of some prestigious award that was offered to him, he would say with his characteristic modesty, “I wonder if they have the right Johnson” or “There are many much better than me”. In that last sentiment he was wrong. I cannot think of anyone better than Ken, neither do I expect him to be surpassed in the future.

Ken was elected a Fellow of the Royal Society in 1982 and to Fellowship of the Royal Academy of Engineering in 1987. He was awarded the Tribology Gold Medal in 1985, and received the 2006 Timoshenko Medal of the American Society of Mechanical Engineers. His acceptance speech for the latter can readily be found on the internet. It affords a shining example of Ken’s clever dry wit and self-deprecating humour. It also served to thank many American friends for technical and social interactions during his two periods of sabbatical leave spent in the States.

Of the many major accolades Ken received, the 2003 Queen’s Medal of the Royal Society gave him the most pleasure. The citation could not be bettered for accurate succinctness: In recognition of his outstanding work in the field of contact mechanics. His work is characterised by elegant experiments, skilful analysis and insightful explanation of observed phenomena. His magnum opus, Contact Mechanics, was published thirty years ago in 1985. I have seen copies on the bookshelves of colleagues all over the world: it has cemented a unique marriage of the words Johnson and contact mechanics in many minds.

Some twenty years after Ken, I joined the Engineering Department as a humble research student, and I initially viewed him from a respectful distance. His rather lined, lugubrious and lived in face, made him seem very senior. I was yet to discover the warmth, the charm and the humour behind what appeared to be a severe façade. I recall the first example of his kindness to me. I had been interviewed for an Assistant Lectureship in the Department, and made a hash of it by becoming involved in what can only be described as an argument (technical!) with a senior Professor on the interview panel. Ken was waiting outside to look after the candidates. I blurted out my huge disappointment at having “blown it”. Later that afternoon I was doing odd domestic jobs at home when out of the Cambridge gloom and damp, cycled Ken, miles off his own way home, to tell me that the job was to be offered to me after all. That marked the beginning of a very special relationship, in which Ken became mentor and friend, both professionally and personally: a relationship also extended to me and to my wife, by Dorothy and the children, Marion, Hilary and Andrew.

In parallel with his academic distinction, Ken was a dedicated husband, devoted father and proud grandfather. His book-lined home was open access to scores of students, colleagues and academic visitors. For years in Park Terrace, overlooking Parker’s Piece, latterly in New Square, the sherry has been poured, lunches and dinners offered and hospitality has flowed. His research students in particular have developed a strong bond over and above academic supervision, and without exception hold him in the highest possible regard.

My wife and I have shared many walking holidays with the Johnson family in the Lake District: many times in rudimentary accommodation in climbing club cottages, sometimes in the Johnson base at Ravenglass, from which Ken could rediscover the mountains of his youth. Our shared love of the mountains lubricated our relationship, as did our northerness, grammar school education, teacher fathers and shared dislike of the trivialisation and commercialisation of our country in the last few decades. I led Ken up his last proper rock climb, C Buttress on Dow Crag, the stamping ground of his formative years in Barrow. A few years later, found the trio Ken, my wife and me, at the foot of Broadstand, a well known mauvais pas on the route between Scafell Pike and Scafell. This was first descended by Coleridge in 1802, most likely in an opium induced haze. We relied on no such artificial stimulants. Although the difficult parts are short, my wife shot up, without hesitation, like the proverbial mountain goat. Ken went second and scratched around clearly discomforted by the drop and unable to make the high reach needed. “Why don’t you climb it by standing on Rod’s head?” came the voice from above. This tactic was readily agreed by Ken and my wife. Fortunately, and perhaps somewhat surprisingly in Ken’s case, nailed boots had given way to rubber soles. You may conjure up an image something like Newton standing on shoulders. The analogy is false. I wilted under the trampling of my head and shoulders. Plastic compression set in: indeed perhaps ratcheting as I was compressed axially under Ken’s repeated loading, and simultaneously expanded in girth: a trend which continues to this day. However, huge laughter was the order of the day when we were all finally united at the top.

Ken’s 70th birthday was marked with champagne on the summit of a very snowy Bowfell. His 80th and 90th birthdays we shared with many other friends at parties in College, the latter only a few short months ago.

The last few years have become increasingly difficult for Ken as his mobility has decreased. Dorothy has been a steadfast and stoic rock of loving care. Two summers ago we delighted to manage to entertain Ken for lunch at Wasdale Head, surrounded by the mountains he so loved. The sun shone, the view was clear. As I helped Ken back into the car to leave, a small tear ran down his cheek. “I don’t think I shall see these hills again”. Sadly this proved to be true.

And we too are all sad because we will not see Ken again.

But in offering our condolences and sympathy to Dorothy, Marion, Hilary and Andrew, let us also rejoice at our privilege of sharing Ken’s life, great achievements and warm human qualities.

Here passes a truly great and fine man: we salute you.