... research topic ... dealt with some of Eddington's ideas and included the writing of Eddington's E-numbers in terms of quaternions. This was a rather surprising area of research. McVittie had long thought that Eddington had lost touch with real physics. According to Kilmister, McVittie considered Eddington's last works "scandalous", and he hoped Kilmister would "get rid of this scandal" ...

Quaternions are used to obtain some of Eddington's results in a general affine space, and a more convenient notation for E-numbers is suggested. As an example, Dirac's equations are derived, their connexion with the affine space of distant parallelism is explained, and Eddington's views on their 'Euclidean' nature are discussed.

The author wishes to thank Professor G C McVittie for suggesting this subject to him, and for helpful advice and encouragement in the course of the work.

A unification of the minimum energy theorems encountered in electromagnetic theory has been stated, and the extension of the theorem to non-isotropic dielectrics and conductors has been made. An application of the theorem to the magnetic field suggests a modified form for the density of the magnetic force-function which agrees which Livens's expression for this quantity.

The quaternion methods of a previous paper are used to formulate clearly the problem of Eddington's 'tensor identities' in both single and double frames. As examples, the single-frame theory is used to calculate the well-known gyromagnetic ratio of the electron, and the double-frame to deduce a complete set of equations, of which Eddington has given a few, which include equations having the form of the field equations of general relativity. A discrepancy with Eddington's results is noted, and reasons given for preferring the present equations.

Most of the results of this paper are to be found proved by longer, but more elementary methods in a thesis (Kilmister 1950). This work was undertaken at Queen Mary College and the author wishes to thank Professor G C McVittie for constant advice, and interest in the course of the work.

In later years Clive recalled the small department he joined as being a very happy place. Departmental bureaucracy was essentially confined to a half hour meeting after the summer examinations although, as he said, it did sometimes run over to nearly three quarters of an hour. In 1954 Hermann Bondi joined the Department and, together with Clive and Felix Pirani, established the gravitational theory group. The King's group quickly became internationally renowned. It was one of a small number largely responsible for the post-war renaissance of research into Einstein's theory of general relativity. He had broad interests, and his publications range over Eddington's work and applications of his algebraic approach in other fields, and also general relativity and unified field theories, special relativity, mechanics (including quantum mechanics) both in relation to teaching and foundations, history and philosophy of science, and applications of mathematics in the social sciences. With his long-term collaborator Ted Bastin he was involved in attempts to construct an abstract approach to physics, and they were founding members of the Alternative Natural Philosophy Association. This latter work he regarded as his most important and the most likely to endure, though perhaps also his most heterodox. He was author of more than a dozen books ...

Kilmister was delighted when Bondi and Pirani were appointed. "Everything changed" he later said although his personal work on gravity was never more than a small part of his research. The latter did include explorations of alternatives to general relativity. For example he undertook one of the early investigations of what later tended to be called Yang's theory of gravity ... Kilmister was elected to the committee of the International Society on General Relativity from 1971 to 1974 but by then his many other activities were crowding out his interest in general relativity ..

It is half a century since I first succumbed to the Eddingtonian magic ... in 'Relativity Theory of Protons and Electrons', which Eddington had published ... in 1936. I had already enjoyed his authoritative 'Mathematical Theory of Relativity' with no more difficulty than that produced by the complex mathematical techniques which were new to me. Looking back on it, it surprises me that I could take in without a qualm so many of the unorthodox philosophical views in that book. But 'Relativity Theory of Protons and Electrons' was a different matter. Another clutch of mathematical techniques was not enough to obscure a radically new position. ...

In 1941 much of [the] background was unknown to me and I was just fascinated by the book on its own terms. As time went on I learnt more and more of the difficulties and the task became that of reconstructing Eddington's work in such a way as to avoid them. In 1945 'Fundamental Theory' appeared after Eddington's death. It was a disappointment to me, for it did not seem to address the real obscurities of the earlier book. I spent a good deal of time clearing up the algebraic aspects of the theory but when this had been done the basic ideas were not much clearer. Yet they continued to dazzle: flashes of insight grouped round a frame of numerical results. I kept returning to Eddington's work and puzzling over it between the other enterprises that filled my working life. I owe a debt of great gratitude to Ted Bastin who often gave me guidance and help over Eddington during this forty-five years.

Years ago books on the history of mathematics, especially those addressed to the general public, were written by second-rate mathematicians who had turned themselves into something less than second-rate historians. More recently things have improved greatly and there are first-rate historians producing works of real scholarship.

In 1967 I was appointed to the Chair of Mathematics (which had been vacant for a year). I found a Department of 11, or rather 10 and 2 halves, one post being shared with the Institute of Computer Science and one with the Philosophy Department. In the course of the next few years both were converted to full posts, giving us a strength of 12. Professor John S Griffith left in 1968 to take up a split appointment between Bloomington and the CSIRO in Sydney (he died only 5 years later). He was succeeded in 1969 by R F Streater, an applied mathematician with very broad interests in pure mathematics. During the next dozen years, when lecturers were relatively scarce, there was a turnover of about one staff member per year, and we were usually able to get people whose interests were represented in the Department, with the result that distinct research groups could be formed, in algebra, logic and quantum field theory. This was also reflected in the growing number of research students, research fellows and the steady stream of overseas visitors to the Department. At the same time the interests of the undergraduates were not forgotten; the syllabus had become more 'algebraic', but efforts were made to provide a balanced fare. In the third year it was possible to attend courses at other colleges, and there was a (2-way) interchange with both University College and Westfield College, and to a lesser extent King's College. At the postgraduate level there was the M.Sc. which was truly intercollegiate, and it could easily happen that the class for an M.Sc. course was larger than one for an optional second year course.

I have many reasons to be grateful to Clive. As a young lecturer I quickly realised that he was among the most approachable, generous and helpful of my senior colleagues, and I picked his brains and benefited from his advice on innumerable occasions. He encouraged me early on to take an interest in what went on in schools by arranging for me to be involved in examining for the London Teaching Certificate and, much later, by suggesting I might like to become Admissions Tutor. And, knowing that I lived a long way out from London, year after year he so organised the timetable that I could avoid too often having to travel uncomfortably and expensively in the rush-hour. Clive was a devoted husband and family man. He and Peggy shared interests in theatre, opera, art, and music, in particular lieder.

He sometimes suffered from insomnia, and would do mathematics to pass away the hours of darkness ...