Thomas MacFarland Cherry 1898-1966

Written by K.E. Bullen.

Thomas MacFarland Cherry's grandfather Edward Cherry was born in England about 1831 and arrived in Australia in 1855. He went first to the Victorian goldfields and soon afterward turned to building, later setting up in Gisborne (Victoria) the business of Cherry and Sons, known for 'Cherry churns' and other dairy appliances. Edward Cherry was a member of the Gisborne Shire Council. In Gisborne, as a childless widower, Edward Cherry married Anne Appleby, née Davies, a widow, who had been born in St Helena about 1825, daughter of a sergeant with the guard of Napoleon.

The elder son of Edward and Anne Cherry was Thomas Cherry, MD, MS, who became a Director of Agriculture in Victoria and was Professor of Agriculture in the University of Melbourne from 1911 to 1916. Thomas Cherry was noted not only as a distinguished scholar but also as a resourceful handyman who could 'fix anything'. He wrote a book on Victorian agriculture and carried out research on cancer which he continued with vigour till near his death at the age of 84.

Thomas Cherry married Edith Gladman, a graduate in classics, who had come to Australia from England when her father was appointed first principal of the Melbourne Teachers' College. Thomas MacFarland Cherry was their second child, born in Glen Iris in outer Melbourne on 21 May 1898. Tom was brought up in Glen Iris in what was then a rural atmosphere. His elder brother, John Howard Cherry was killed in France in World War I. Two other brothers, Henry Lister Cherry and Richard Ormond Cherry (now Senior Lecturer in Physics in the University of Melbourne), and one sister, Margaret Lilias Cherry, survive him.

Tom Cherry was a pupil at Scotch College, Melbourne, where his bent for mathematics soon revealed itself. He went to the University of Melbourne as a resident student at Ormond College, and in 1918 graduated with first-class honours in mathematics, being awarded the Dixson and Wyselaskie Scholarships.

He then had a short period in Army service and some Air Force training which, according to some notes he has left, enabled him 'to learn telegraphy and solo whist'. In 1919, he began a medical course in the University of Melbourne, but his godfather Sir John MacFarland (the Chancellor of the University of Melbourne) offered to advance him funds to further his mathematical career in Cambridge.

He thereupon entered Trinity College, Cambridge, and at the end of his first year gained first-class honours in Part 2 of the Mathematical Tripos, becoming a Wrangler with B-star. He was awarded a Senior Scholarship and an Isaac Newton studentship at Trinity College, graduated BA (Cambridge) in 1922 and PhD in 1924, and was elected to a Senior 1851 Studentship.

He was a Fellow of Trinity College from 1924 to 1928. Inside this period he carried out lecturing duties during three terms in 1924-25 as an Associate Professor of Applied Mathematics at the University of Manchester, deputising for E.A. Milne during Milne's prolonged illness. In 1927, he deputised for C.G. Darwin for one term at the University of Edinburgh.

In 1929, Cherry relinquished his Trinity College Fellowship to accept the Chair of 'Mathematics, Pure and Mixed' at the University of Melbourne. In 1952, this Chair was replaced by separate chairs in Pure and Applied Mathematics and Cherry, with some hesitation, elected to take the Chair of Applied Mathematics, which he occupied till his retirement in 1963. In 1950, he received the ScD degree of the University of Cambridge.

In the latter part of his life, the affairs of the Australian Academy of Science became one of his principal interests, and his years of service on the Academy Council substantially exceed that of any other Fellow to date. He was a Foundation Fellow and member of the first Council (1954-5), Secretary A (1956-9), and President (1961-5).

The following honours came to him: He was Pollock Memorial Lecturer in the University of Sydney, 1948; Lyle Medallist, Australian National Research Council, 1951; and was elected a Fellow of the Royal Society in 1954. He received honorary degrees (DSc) from the Australian National University and University of Western Australia in 1963, and became a Knight Bachelor in 1965.

Among his other principal interests were the affairs of the Australian Mathematical Society of which he became the first president in 1956, and the development of Latrobe University in which he played a prominent part. He held office as president of the Mathematical Association of Victoria in 1929-34 and 1946-8, and was foundation president of the Victorian Computer Society, 1961-3. He was a member and chairman of the Mathematics Standing Committee of the Schools Board of the University of Melbourne from 1929-52, and was personally responsible for major re-draftings of mathematical syllabuses in Victorian secondary schools on two occasions. In 1958, he was president of Section A of ANZAAS.

Cherry's research and contributions to knowledge took several turns during the course of his academic life, though most of his work was closely related to his chief love which was classical mathematical analysis.

In his early years in Cambridge, on being given some problems in Statistical Mechanics to investigate, he soon found his interest turning to the underlying differential equations. The theory of differential equations, particularly the equations that arise in Dynamics and Celestial Mechanics, was his main research field for a number of years. Over the period 1923-38, he published 13 papers in this field, bearing mainly on periodic solutions and relations between different manifolds of periodic solutions, and on the possible complexities of non-periodic solutions. In 1966, some earlier unfinished work was published.

In the late 1930s, Cherry turned to an interest in mathematical logic. He spent some time mastering Gödel's theorem, but though in this field he read a great deal and entered into discussions with Melbourne philosophers, he did not publish any papers. In 1937 he was asked to give a lecture (published by the Melbourne University Press) in commemoration of the tercentenary of the publication of Newton's  Principia.  This led him to an intensified interest in the foundations of the theory of Mechanics. In the notes he has left, he wrote: 'While I am interested in the facts of Nature, I am much more interested in scientific theories, and particularly in fundamental questions, e.g. whether the classical principles of dynamics form a sufficient foundation for Statistical Mechanics. When such questions are formulated mathematically, they become problems in pure mathematics, and it is really to this subject that most of my work belongs. On the fundamental questions themselves I have perhaps arrived at understanding, but have found nothing sufficiently interesting to publish.' Actually, Cherry did present some of his ideas on the foundations of Mechanics in his ANZAAS address, which was published in 1958. The approach in this paper is rather severely formalistic and mainly leaves aside questions of uncertainty and inductive inference.

During World War II, Cherry's interests turned to questions of a more practical nature, to which he applied his skills in mathematical analysis. Examples are questions on the detection of aircraft by radar, and on the pressure and temperature generated in a film of nitroglycerine when hit by a hammer. The war also sowed the seeds of a later interest in electronic computers, an interest which grew in his subsequent post-war researches. Those with whom he worked during the war were in high praise of his physical insight as well as of his formal mathematical powers.

In 1945, his attention was called by a former pupil to a class of problems in the flow of gases, and in particular to a method (the hodograph method) which, it was thought, might yield detailed results of much physical interest at the hands of a good mathematical analyst. Previously no more than crude approximation methods had been applied to the problems. Cherry succeeded in deriving formally exact flow patterns of importance to trans-sonic flows past aerofoil shapes and to the design of supersonic wind tunnel shapes. This new activity led him to publish some 15 further substantial papers from 1947 on, and he was elected to the Royal Society in 1954. The papers included several on auxiliary mathematical analysis, mainly on the approximation to functions by asymptotic expansions and the numerical summation of slowly convergent series. Around this time, Melbourne University acquired the electronic computer constructed by T. Pearcey of the CSIRO, and Cherry interested himself not only in the programming detail but also in the more practical properties of the computer.

Cherry's research career was that of an individualist. His notes state: 'By taste, or upbringing, I have preferred always the "do it yourself" method. This began when, at the age of seven, my attendance at school involved a walk of nearly four miles every day. With the help of prizes and scholarships, whose attainment involved little effort for me, I have been practically self-supporting since the age of 17. I have "directed" the initial research efforts of a fair number of students, but by force of circumstances, reinforced by inclination, I have not tried to form a "research school".'

Cherry was intensely interested in the teaching of undergraduates in his Melbourne University Department. On this, he wrote: 'For over 20 years I was responsible for the whole mathematical syllabus, pure and applied, and I have always regarded the associated teaching as my chief responsibility. For over a decade the stint was four courses of lectures per term. Since I am really attached to teaching this was no burden. At one time or another I have taught every subject in the curriculum, at all levels.' One of his greatest prides was the success of the cream of his students in their subsequent careers and his notes state 'I am most conscious of the two-way reaction between teaching and research.'

When I went to Melbourne in 1940 I found a Department of Mathematics which, in respect of fine attention to undergraduates' needs and highly efficient organisation, I have not seen bettered in any of the Universities I have since visited in many countries. The foundations for this efficiency had been laid by J.H. Michell, FRS, Cherry's immediate predecessor in the Melbourne Chair and a world figure in Applied Mathematics. Cherry was Michell's star pupil and set out to perfect the work on the undergraduate structure which Michell had begun.

Cherry had also, when a student in Melbourne, come under the influence of Professor E.J. Nanson, and of D.K. Picken and C.E. Weatherburn of Ormond College. Picken was still in Melbourne (as Master of Ormond College) at the time of my arrival and I was able to learn something of his influence on Cherry. Picken had a first-class logical brain and might have had a significant mathematical career were it not for the inhibiting effect of an unbridled passion for formalism. Cherry, though aware of Picken's limitations, had a great respect for Picken and told me that it was Picken who first imbued him with the importance of mathematical rigour. From talks with both Picken and Cherry, I gathered the impression that Picken also contributed to the development of one of the strongest traits in Cherry's disposition, namely, thoroughness and extreme attention to detail. Cherry was, however, constitutionally incapable of ever being other than thorough.

Contributing also to the quality of Cherry's undergraduate department, as I saw it in the 1940s, was something in the nature of a scout-like approach which had both its pros and its cons. (Actually, scouting was another major activity of Cherry, from his Cambridge days onward.) The predominant note in the department was that service to students and the department must be placed above all else. Cherry himself was devoted to the welfare of the department and students and took great interest in questions of pedagogy, syllabus and examinations at the School as well as the University level. He himself was a very competent lecturer, methodical and lucid, with his material meticulously ordered and errorless.

In Victoria, in contrast to the circumstances in some other Australian states, the University of Melbourne had virtually full control over syllabuses and examinations in the main secondary school system. The University conducted not only the Matriculation, but also the School Leaving and Intermediate examinations. In much of this work (and not wholly confined to mathematics) the guiding hand was Cherry's. In mathematics, he built up model relations with secondary school teachers and when he had won their confidence delegated important sections of work to them.

Part of his strength lay in the research frame of mind he brought to bear in problems of education and examination. Where many senior academics have tended to decree, and still decree, on these matters without appreciating the depth of underlying problems, Cherry never acted without intense prior fact-finding and investigation. Thus he was equipped to give informed (firmly, but mildly expressed) rejoinders to professional educationists with differing viewpoints and usually would quickly win the opposition round.

By the time I had arrived in Victoria, he had acquired an almost god-like stature among the mathematical teachers of the State, and the quality of preparation of entrants to Melbourne University was streets ahead of that in any other Australian State. In spite of current fanfares in some other States, it is doubtful whether school education in Mathematics and Physics will for many years approach the quality it reached in Victoria in Cherry's time. Among several other things, I owe Cherry a personal debt for what I learned when in Melbourne about the principles of setting and assessing examination papers – principles which were arrived at through solid research and controlled experiments instituted by Cherry. I have nowhere seen a fairer assessment of students' results than in Melbourne, nor more intelligently conducted examinations.

If any criticism could be made of the Melbourne department in those days, it could only be of the extent to which devotion in such matters was carried. I sometimes felt that the emphasis on undergraduate needs, admirable as it was in so many ways, yet carried with it an undue tax on the staff's research activity. For most of the third term, for example, the time devoted to preparing and criticising examination question papers by the entire department made it next to impossible to concentrate on any deep research. There was also a severe tax on research energies in the second term – in Melbourne's foggy winter when colds and influenza are rife. Even though the staff was quite small in those days, the rules of the department required every undergraduate lecture to be given – when a staff member was away sick others would take over his courses and then themselves often become sick. Thus one might have suddenly to drop research and reading for periods inside the winter terms to prepare and deliver sometimes up to two full additional courses. In the changed conditions of today, the very thought of the total lecture load sometimes reached, a load which Cherry himself fully shared, would make the average modern young lecturer go pale. Many miscellaneous extra-curricular tasks involving mathematical effort were carried out by the department in a volunteering spirit. Staff members were expected (though not quite directed) by Cherry to work with him on these tasks, often at zero notice (At the same time, it should be said that many of the staff, especially those who were Melbourne graduates, loved working with Cherry on his enthusiasms.) While these matters need to be stated to give a balanced picture of life in the department, they should not detract from the outstanding fact that Cherry built up in Melbourne a Department of Mathematics of enviable reputation. Its fruits are to be seen in the achievements of and posts held subsequently by many of the department's graduates.

For my own part, the five years I spent in Cherry's department were an invaluable contribution to my education and to my qualifications for a Chair. Even though conditions in New South Wales have made it difficult for me to bring to bear all the features I most admired in the Melbourne Department, I had the privilege of seeing in Melbourne a great machine in action and of profiting from my observations of its greatnesses as well as its limitations. It was also a privilege to work in the presence of one of Australia's best mathematical analysts of the time.

A further interesting passage in Cherry's notes refers to his regret at having to relinquish, in 1952, the title of 'Professor of Mathematics, Pure and Mixed'. He always felt that this title provided the best description of his interests and it was only after hesitation and with some reluctance that he elected to take the Chair of Applied Mathematics. He regarded himself as essentially a pure mathematician – though his interest was not in modern abstract mathematics – whose tastes led him intermittently to use his analytical skills in a variety of contexts. Where many applied mathematicians nowadays put context first and the mathematics second, mathematical analysis came first with Cherry.

I first met Tom Cherry in 1931 when he and his wife Olive graciously entertained me in their home when I was a New Zealand student passing through Melbourne on my way to England. After 1946 when I left Melbourne University, our paths continued to cross a great deal, partly through common interests as holders of Chairs of Applied Mathematics, but even more so after 1954 when the Australian Academy of Science was founded and brought us into close contact on a number of national tasks.

I thought he rose to his best as a Secretary of the Academy. In the early part of the International Geophysical Year, for example, when H.C. Webster and I carried heavy loads as convener and chairman of the national committee, Cherry was a tower of strength. Where some other Academy officers appeared indifferent to the necessities of Australia's IGY contributions, Cherry saw the needs clearly and worked hard as Academy Secretary to obtain indispensable Government support. He is one of a quite small number of men who enabled Australia's reputation in respect of the IGY to be saved. Again, during the formation of the International Scientific Committee on Antarctic Research, Cherry worked hard behind the scenes in Australia's interest. These are two examples in which I had close first-hand knowledge of what he did. But the Academy Secretaryship also brought out in him latent qualities that surprised even many of his friends who had known him closely in the Victorian setting.

He was also successful, though sometimes slightly controversial, as President of the Academy. As third President, Sir Thomas Cherry saw the Academy through an important epoch in its history when its place as an Australian institution was beginning to emerge. He had the distinction of admitting His Royal Highness, the Duke of Edinburgh, as a Royal Fellow of the Academy, and of receiving the Grant of Arms to the Academy. During his presidency, the Basser Library was opened, Senior Fellowships were established by the Academy, and active steps were taken to form discussion groups with representative industrialists.

Cherry had no hesitation in taking strong and positive action on a number of occasions when he felt this to be in the Academy's interest. He had strong views on broadening the basis of Academy membership. In his Quadrennial Review as retiring president, he wrote in 1965: 'I make no secret of my own opinions: (1) that the tendency of the Academy should be towards a suitably circumspect and marginal broadening of the basis for its membership; (2) that its tendency in fact has not been this; (3) that my own attempt to propagate the less conservative policy was badly judged; for example, I tried to go too quickly.' It remains an acutely controversial question within the Academy as to the extent, if any, to which the Academy ought to change its policy in respect of balance between pure and applied science.

In most of his outlooks, Cherry took an Australian viewpoint, though he also had a great regard and liking for British ways. He looked increasingly toward the international scientific scene after he became Secretary A to the Academy. As Academy President, his chief international venture was his enthusiastic acceptance of an exchange of delegations between the Academy and the Academia Sinica of Peking, which was not without its controversial aspects. While there was general agreement among the Australian scientific community that the President of the Academy should foster all possible good relations with Chinese scientists, irrespective of official Government attitudes, there was some concern that the President should take the further step of expressing publicly a view on the question of the admission of China to the United Nations. Many felt that an Academy president should refrain from declaring on a major question involving expert knowledge outside the field of the Academy. At the same time, none could ever question Cherry's sincerity in doing what he thought right, even if unpopular. He was a man of principle.

From examples such as the above, it will be correctly inferred that Cherry was a strong and fearless character. Yet he was also among the gentlest of men. The furthest he ever went toward expressing displeasure was a faint flicker of an eyebrow which rarely failed to quell anyone who ventured too far in directions he did not approve of. He was not only a gentle man, but a man of kindliest intentions. He was also a man of austere integrity. One always knew where one stood with him even if one sometimes had opposed views. When one did disagree, he was a formidable opponent – in a quiet way. He was a man without malice or grudge, with strong views on his purpose in life. Most people who knew him well rather loved him or at least admired him, though few came close to being really fully in tune with him. Many who did not know him well thought him cold, but that was a mistake: he had a warm disposition below the surface. He was a doer rather than a talker. He was also a philanthropist and personally generous in an unostentatious way.

He had fairly definite political views, at times somewhat, but not very far, left of centre. He was essentially an independent thinker: one could not imagine him having any political affiliation. He once told me that he thought one should vote left to get some new ideas into government and then vote right a few years later in order to get straightened out the mess that socialists always make of things. In his earlier years his attitude to rank and privilege could sometimes be pointedly offhand and he was casually scornful of the fopperies of society. In later years his attitudes changed a little, though he by no means became strongly conservative, as his record as Academy president shows.

Not only did he think as an Australian but he loved the Australian countryside. He tramped almost everywhere in Victoria and loved expounding on the local geology and flora and fauna. He lived a vigorous and disciplined life with few frills. Camping and mountaineering were another major part of his activities. His notes state: 'My love of camping and mountaineering connects in one direction with "do it yourself" and in another direction – via the shapes of hills – with geometry and mathematics.'

The stories of his robust physique are legion. The following example, relating to an incident on an outing of the Melbourne University Mountaineering Club, of which he was president, gives an interesting glimpse of his ways. A group including Cherry (aged about 50 at the time) and others all much younger, had come after a long day's tramping to the foot of an 800 feet hill standing between them and their destination. The worn and tired young men and women put it to the president that the group go round the hill and not over. 'The route is shorter over the hill' came the unyielding reply, and before protests could become articulate, the president was striding rapidly upward at a pace that belied his years, with the rest of the group straggling mournfully behind.

It was thought by all his friends that Cherry would continue after retirement into a long period of mental and physical activity. It came as a great shock when in early 1965 he was stricken with a heart attack. This followed a grim 30-hour struggle for survival in which he and his son-in-law were benighted in a precipitous area without food or water and in summer heat. With characteristic courage, after a short convalescence, he resumed his interrupted activities and even added to them, for example, in his work for Latrobe University. But he succumbed to a second heart attack on 21 November 1966. He leaves behind him his widow, Lady Olive Cherry, and only daughter Jill, now Mrs J.D. Stowell of Newcastle, NSW A great tribute is due to Lady Cherry who placed her husband's interests first in all things and unobtrusively gave him precisely the support which a man of his type needed.

The writer would like to acknowledge gratefully the help he has received from several of Sir Thomas Cherry's friends in compiling this article, and especially from Professor E.R. Love who kindly supplied a quantity of the biographical material used and checked various details.