Albert Einstein made three visits to Oxford between 1931 and 1933, staying for a month in the spring of each year. For our understanding of Einstein's work, the Rhodes Memorial Lectures that he delivered during his first visit are of special interest. They show him in a period of intense rethinking of his cosmological views in the light of Edwin Hubble's recent evidence in favour of an expanding universe, an idea that Einstein had hitherto opposed. The lectures, heavily mathematical and delivered in German, were challenging. Nevertheless, they were well received, and Frederick Lindemann (later Lord Cherwell) saw them as a springboard for a continuing association between Einstein and the University's Clarendon Laboratory. To that end, Lindemann persuaded his college, Christ Church, to invite Einstein for a month in 1932 and each of the four years that followed. The arrangement, part of Lindemann's plan to revitalize Oxford physics, was soon overtaken by political events in Germany and Einstein's emigration to Princeton in October 1933.

Albert Einstein came to know Oxford well, and he in turn was known there and widely respected. He made his first visit in June 1921, when Frederick Lindemann, recently elected to the Dr Lee's Professorship of Experimental Philosophy, took advantage of Einstein's brief presence in England (en route back from the USA to Germany) to drive him from London to Oxford for the day.1 His first extended visit, however, did not take place until a decade later. Then, in May 1931, he stayed in Lindemann's college, Christ Church, for almost a month, delivering a series of three Rhodes Memorial Lectures and, on the day of his last lecture, receiving an honorary doctorate of science. Einstein's acceptance of the invitation to give the lectures was a triumph both for Lindemann and for Oxford. The celebrity that Einstein had acquired following the observation of the bending of light passing close to the sun in 1919 had served to make his presence an incomparable prize for an ancient university seeking to make a public statement of its engagement with the modern world.

More specifically, it was a prize for Oxford physics. Since taking up his appointment in the spring of 1919, Lindemann had worked hard for a revival of research and teaching in the university's Clarendon Laboratory after the somnolent years of Robert Bellamy Clifton's long occupancy of the chair.2 One way forward would have been for him to establish a major research school of his own, building on the early promise of his doctoral thesis of 1910, prepared at the University of Berlin under Walther Nernst. The thesis, on specific heats at very low temperatures, had set Lindemann in the elite of young, potentially leading figures in international physics. But, once in the Oxford chair, Lindemann performed little original work and looked instead for other ways of promoting the discipline in the face of the combined obstacles of the precarious financial state of the university and the weight of conservative prejudice against the sciences. In this aspect of his mission, he saw Einstein as a crucial ally.

Oxford: the Rhodes Memorial Lectures

With an invitation for Einstein very much in mind, Lindemann perceived the opportunity offered by the Rhodes Lectures as soon as they were established, in 1926, under the auspices of the Rhodes Trust, Oxford's memorial to Cecil Rhodes.3 Since Rhodes's death in 1902, his bequest of £4 million had been invested to create the scholarships that had brought young men (not yet women) from across the British Empire, the USA and Germany to study at the university. The decision to found the lectures was by no means a natural extension of what had gone before. In fact, at a time of financial uncertainty, and with the Trust's investment income falling and the cost of the scholarship system rising, it represented a hazardous new departure. That it came about owed much to the cautiously modernizing spirit that characterized the Trust's post-war policies, especially after the appointment of Philip Kerr, the future 11th Marquess of Lothian, as General Secretary to the Trust in 1925. Kerr's liberal inclinations, already evident in his role as ‘political director’ of the Daily Chronicle (later merged with the Daily News to become the News Chronicle) between 1920 and 1922, were a driving force in his determination to align the Trust with a moderate, reflective form of imperialism more in keeping with post-war British attitudes towards the Empire.4 But Kerr also had in view the gathering taste for reform within the university. An important catalyst in this movement was the commission of inquiry into the universities of Oxford and Cambridge, launched in 1919 under the chairmanship of the former prime minister Herbert Asquith.5 A central conclusion of the commission's report, published three years later, struck at the heart of the ancient universities' academic insularity:

It is a disaster that, at a moment when we have become far more deeply involved than ever before in the affairs of countries overseas, our highest academical class is condemned through poverty to knowing little or nothing of life or learning outside this island.6

As the commission insisted, if Oxford in particular was to maintain its standing among the English-speaking universities of the world, it had to recognize the ‘poverty’ of its provision for research and travel and seek whatever means it could to look outwards.

On that crucial point, Kerr found a powerful ally in the Oxford historian, Rhodes Trustee and Warden of New College, H. A. L. Fisher. As a Member of Parliament from 1916 to 1926, president of the Board of Education under Lloyd George for most of those years, and a leading instigator of the Asquith Commission, Fisher had acquired immense authority in the cause of educational reform, especially where the interests of Oxford were concerned. His mark on the lectures was as evident as Kerr's, and both men gave free rein to their ambitions. As part of a determinedly outgoing agenda, the Rhodes Memorial Lectures were intended to bring to Oxford men and women from outside Britain who had displayed exceptional distinction in public life, the arts, letters, business or science and who would not otherwise be likely to visit the university. Everything about the lectures was cast accordingly. An invitation to lecture was designed to be a signal honour, ‘one of the great world prizes, analogous, for instance, to the Nobel Prize’, and it was assumed that, in return for three public lectures and a requirement to reside in Oxford for one of the university's three eight-week terms, a fee of £500 would be sufficient to attract the most eminent names from across the world.7 As an early planning document rather complacently put it, ‘There are very few people who would not thoroughly enjoy spending, say, the Summer Term in Oxford where he would certainly be invited from one Common Room to another during his stay.’8

From the start, Einstein was seen as a strong candidate, and his name was on the Trustees' first shortlist of those who might be invited, along with the former Canadian prime minister Sir Robert Borden and the former prime minister of South Africa and member of the British Imperial War Cabinet Jan Smuts.9 The only immediate impediment was the known weakness of his English, which was deemed to rule out the possibility of his being invited for the first series, planned for 1927.10 The invitation eventually went to Borden. Lindemann, though, was not discouraged. By now, he and Einstein had been good, if not intimate, friends for 15 years, since their meeting at the Solvay conference on physics in Brussels in 1911. As a fluent German speaker (despite his British nationality and resolute predilection for British culture) and joint secretary of the conference (with Louis, duc de Broglie), Lindemann had easy access to Einstein. ‘I got on very well with Einstein’, he wrote to his father after the conference; only Hendrik Lorentz had made a greater impression on him.11 It was an admiration and affection that survived undimmed until Einstein's death in 1955.

The first concerted attempt to have Einstein elected as a Rhodes Lecturer, in the summer of 1927 (for 1928), proved a confusing affair. Despite continuing anxiety about his deficiencies in English, a formal invitation was issued in late June, and there followed a campaign to persuade him to accept or, in the event of his declining, to consider an invitation for a subsequent year. As a driving force behind the invitation, Lindemann was joined by Fisher, in his capacity as a leading Rhodes Trustee. It was Fisher who arranged for the former Labour Lord Chancellor Richard (Viscount) Haldane (who had hosted Einstein and his wife, Elsa, during their visit to England in 1921) to write, and for the German Foreign Office to be enlisted to help, through the Weimar politician and former diplomat Johann Heinrich von Bernstorff.12 Lindemann, too, was asked to follow up with a personal approach.13

Einstein's reply came quickly, but it was disappointing. In letters to Haldane and Lindemann in early July, he declined the invitation on the grounds of ill health, his limited English and unspecified commitments to colleagues that an extended absence from his posts at the Kaiser Wilhelm Institute for Physics and the University of Berlin would make difficult; in addition, as he put it to Lindemann, the material he might present would be of ‘insufficient up-to-date interest’.14 Soon, however, he had second thoughts. In late August, he told Lindemann that he would be willing, after all, to accept the invitation if, as Lindemann appears to have suggested, his stay could be reduced to four weeks from the stipulated eight.15 But Einstein's change of heart, followed by a delayed confirmation of his acceptance via the German Embassy in London, served only to sow confusion.16 By now, plans for an invitation to the educational reformer and biochemist Abraham Flexner were already well advanced, and Flexner went on to give the 1928 lectures on ‘The idea of a modern university’.

A rapid exchange between Lindemann and Fisher resulted in the suggestion that, with 1928 now out of the question, Einstein should be invited for 1929,17 and Fisher duly issued the invitation, with the tentative suggestion that such a long lead time might allow Einstein to plan to be in Oxford for the full eight weeks.18 Once again, however, negotiations proved difficult. After a winter in which the Trustees believed that he would be giving the 1929 lectures, Einstein withdrew, citing heart problems and his doctor's advice that he should avoid the strain that a stay in Oxford would entail.19 And there the matter rested until 1930, when renewed interest on the part of the Rhodes Trust and the undimmed resolve of Lindemann and Fisher finally paid off. It helped that the lectures had now recovered from a somewhat rocky start. The first series, on ‘Canada in the Commonwealth’ by Borden, had been only moderately successful: attendances had been disappointing, and Kerr had not spared Borden's feelings in a withering reaction to a draft of the first two lectures, which he judged to be ‘unnecessarily dull … too much history, too little interpretation … almost, I might say, a catalogue of persons and events’.20 But Flexner (whose internationalism and advocacy of advanced study and research as essential elements in higher education would have been music to the ears of reformers in Oxford) and the French historian Elie Halévy, lecturing in the spring of 1929 on the ‘The world crisis of 1914–1918: an interpretation’, had done much to restore the reputation of the lectures and to refine their function as a window on worlds beyond Oxford.21

If any concerns remained, they were removed by the unprecedentedly successful series that Smuts delivered in November 1929 on ‘Cecil Rhodes and some modern world problems’.22 Interest in the lectures was such that they were delivered in a packed Sheldonian Theatre, rather than the natural venue in the smaller Milner Hall of Rhodes House, the recently completed headquarters of the Rhodes Trust. The chances that Einstein could repeat success on that scale were remote. But his celebrity overrode continuing anxieties about the recondite nature of his science and the gathering certainty that he would speak in German. Correspondence beginning in May 1930, mainly between Lindemann and Kerr, now the 11th Marquess of Lothian, shows him to have been the first choice for the 1931 lectures, ahead of the alternatives of Lord Irwin (the future Lord Halifax), Viceroy of India, and the German chemist and senator Carl Bosch.23

Thereafter, the resolve to land Einstein on almost any terms never wavered. Even when Einstein reported to Lindemann that his doctor had advised him to go back on an initial informal agreement to give the lectures, Lothian was not deterred.24 As he put it to Lindemann, perhaps Einstein might be persuaded just to ‘deliver one or two important lectures and spend at any rate a week or two in the University’.25 The mixture of persistence and flexibility in setting the terms of the invitation finally won the day. By 4 October 1930 Lindemann could report from Berlin that Einstein would be pleased to come,26 and in mid-October the formal invitation for him to deliver at least two lectures, in return for the usual fee of £500, was issued.27 Further delay followed, but a month later (following a persuasive meeting with Lindemann in Berlin) Einstein accepted.28

Between then and Einstein's time in Oxford, an extended visit to the USA (his second) intervened. Most of it was spent at Caltech in Pasadena, and it was from there that Elsa wrote to confirm that her husband would arrive in England on 26 April 1931 and stay for about four weeks.29 In the event, Einstein landed in Southampton a few days later than that, on 1 May. Determined that the visit should be a success, Lindemann spared no effort in giving him a welcome appropriate to an international celebrity. When Einstein's ship, the luxurious Albert Ballin, arrived in Southampton from Hamburg, Lindemann went aboard to greet him and took him ashore in a motor launch. There followed a leisurely drive in Lindemann's chauffeur-driven car, first to Winchester, to visit the cathedral and ancient school, and then on to Oxford, in time for dinner in Christ Church.

Einstein found his initiation in Oxford life an uncomfortable experience. The black-tie code of high table and the absence of women in a still rigidly all-male community made for an evening that he described in his diary as a ‘bizarre and boring affair’.30 The rituals of dining and the formality of relations between colleagues must have appeared a world away from the vibrant modernity of the Weimar culture Einstein had left behind in Berlin. As a committed internationalist, he would also have sensed the prevailing parochialism of interwar Oxford. But, in its quietly conventional way, Christ Church did what it could to make him welcome, and he settled comfortably enough into a set of rooms normally occupied by the classical tutor and aesthete Robert Hamilton Dundas, currently on leave from the college in India. Once there, looking onto the imposing Tom Quad, he began to appreciate the tranquillity of college life, the university's rich musical offerings and the understated beauty of the countryside and English architecture.

With his uncomfortable first dinner behind him, Einstein also found that there was good company to be had beyond the walls of Christ Church. In a busy first week, he was glad to see again the classical scholar and humanist Gilbert Murray, a fellow member of the League of Nations International Committee on Intellectual Cooperation since its foundation in 1922 and currently its president. Later in the week, after a dinner in Trinity College, he attended a lecture by the Rouse Ball Professor of Mathematics, Edward Arthur Milne, whose interests at the time were turning increasingly to relativity and cosmology.31 Einstein admired Milne (despite divergences between their positions on theory that were to become more marked in later years), and the two men were to see a good deal of each other during this and Einstein's subsequent stays. As his diaries show, Einstein was warming to Oxford.

May 1931

After his week of acclimatization, Einstein's duties began in earnest on Saturday 9 May. At noon, in Rhodes House's Milner Hall, he delivered the first of what were to be three lectures under the general heading of ‘The theory of relativity’. The lecture, entitled ‘The theory of relativity: its formal content and present problems’, appears to have been, at best, a qualified success. The difficult physics that Einstein discussed was made all the less accessible by his lecturing in German, which few in the audience of 500 were able to follow easily. With the last resort of having the lectures taken down in shorthand abandoned at Einstein's request, apprehensions at what promised to be a formidable ordeal for most of those attending grew.32 An understandably anxious Roy Ridley, a literary scholar at Balliol College who had been asked to report on the lectures for The Times, foresaw the difficulty he would have. In a cry for help to Lindemann on the eve of the first lecture, he admitted that he would write his account without attending: ‘it is no use my going to the lecture, since even if I could understand the matter, which I couldn't, I don't know even any German’.33 Lindemann simply referred Ridley to an eight-page printed translation of Einstein's summary of the lectures that had been prepared, probably with Lindemann's help, in 1000 copies; Lindemann's comment that he doubted whether Ridley would find it very useful conveyed even his own anxieties.34 The reports that eventually appeared in The Times suggest that Ridley contented himself with the summary, and most other correspondents seem to have done likewise.35 Only the reports on this and the other lectures in Nature and the Oxford Magazine gave evidence of any but the most rudimentary grasp of the issues.36

With Einstein speaking from notes and providing no written text, other than the summary, the detailed content of the lectures is hard to reconstruct. It is evident, however, that in his first lecture he made a brisk, not to say challenging, start. He pitched straight into the mathematical meat of the passage from the pseudo-Euclidean four-dimensional space of special relativity to the Riemann metric, also in four dimensions but in a ‘curved’ non-Euclidean space, of the general theory. Building on that exposition, he went on to broach the fundamental unresolved challenge of relativity: that, while the general theory dealt satisfactorily enough with gravitation (something that the special theory had not done), it was unable to provide for a logical understanding of the electromagnetic field and its connection with matter.37

In his second lecture, a week later, before an understandably reduced audience, Einstein turned to ‘The cosmological problem’. The subject was slightly more accessible than the first, and he himself was happier with it. With regard to the content of this lecture, unlike the other two, we have the additional resource of the celebrated blackboard that he used while speaking (Figure 1). The blackboard confirms that he used the lecture to present some of his most recent, and now rapidly evolving, ideas. The treatment was very much of the moment, specifically the spring of 1931, and it is that which makes the lecture a landmark in the rethinking that led Einstein from his long-held belief in a static universe to the alternative paradigm of a universe in a state of expansion.38 Figure 1. The blackboard that Einstein used in the second of his Rhodes Memorial Lectures on 16 May 1931 (Museum of the History of Science, Oxford, inventory no. 44725). The blackboard was salvaged immediately after the lecture and presented to the Lewis Evans Collection (now in the Museum of the History of Science) by the Warden of Rhodes House, Sir Francis Wylie (see note 46). © Museum of the History of Science, University of Oxford. (Online version in colour.)

A crucial stimulus to the transition in Einstein's thought had been his visit to Caltech in Pasadena at the beginning of the year. In a two-month stay in California, through January and February 1931, Einstein had renewed his acquaintance with Edwin Hubble and had talked with him about the now incontrovertible evidence of red shifts in the spectra of extra-galactic nebulae. As a ‘cautious empiricist’ (Helge Kragh's words), Hubble was careful not to interpret the shifts as evidence of an expanding universe.39 But his observations, announced in 1929, inevitably turned the thoughts of others, including Einstein, to that possibility. They also resurrected interest in earlier theoretical discussions, notably by Willem de Sitter (1917), Alexander Friedmann (1922 and 1924) and Georges Lemaître (1927), which came subsequently, and with varying degrees of plausibility, to be interpreted as foundations for the abandonment of the static model.40

The convergence of Hubble's observations with the growing body of theoretical analysis made a mark on Einstein's thinking that became evident in the three months or so immediately preceding his Oxford lectures. An initial brief flirtation with a steady-state model that would have entailed the continuous formation of matter in an expanding universe led nowhere: probably recognizing that his discussion was flawed, Einstein never published the short paper on the subject that he seems to have drafted at Caltech early in the year.41 Soon, in any case, he had a more promising solution. What he now saw was that the field equations of general relativity could, after all, be made to accommodate the idea of a finite universe expanding at a rate broadly compatible with the new evidence about the red shift. But on one condition. This was that he turn his back on the ‘cosmological term’ (more commonly known as the ‘cosmological constant’, Λ) that he had incorporated in his field equations since 1917 precisely to sustain the static model.

The constant had essentially the effect of a repulsive force that countered Newtonian attraction and thereby prevented the collapse that would have followed if gravity had been the only force acting between matter. Well before 1931, Einstein had come to regard the constant as a mathematical construct that was at once ‘theoretically unsatisfactory and empirically uncalled for’.42 It was therefore with evident relief that he found a way of doing without it in the cutting-edge reworking of his ideas that he presented in a paper submitted in mid-April to the Prussian Academy and published on 9 May, the day of his first Oxford lecture.43 In the paper, written in no more than four days in early April, he looked back to Friedmann's demonstration of 1922 that solutions of the field equations of general relativity were possible without the constant and that they were compatible with the paradigm of an expanding universe. At the time, and on through the 1920s, Einstein had rather peremptorily disregarded Friedmann's conclusion. But he now invoked the calculations by Friedmann as the foundation for his decision to abandon the static model for good. Setting the cosmological constant to zero in his reformulation of Friedmann's analysis, he proposed instead a model in which expansion could be followed by contraction, although in the paper he did not discuss the contraction phase. It was this treatment that he presented in his second lecture.

The few in the audience for the lecture who possessed the necessary mathematical and linguistic tools and familiarity with the current literature on cosmology would have appreciated that they were witnesses to a historic turning point in Einstein's thinking. And those who were even distantly attuned to current discussions among physicists and reports that filtered into the press might have recognized Einstein's change of heart as part of a broader tide of support for the dynamic model. But the more immediate, and very specific, influences that led to his re-evaluation of Friedmann would have escaped all but those most closely involved in the intense cosmological debates of 1930–1931. One such influence was the work of Arthur Eddington, director of the University of Cambridge Observatory and Plumian Professor of Astronomy. Eddington's recent demonstration of the instability of Einstein's static model, which the two men would certainly have discussed when they met in Cambridge in June 1930, struck at the heart of Einstein's cosmological position; as Harry Nussbaumer has argued, it seems to have marked the starting point of Einstein's ‘reluctant conversion’ from his static model.44 The other influence, also dating from 1930, was Einstein's engagement with the crucial 1927 paper of Georges Lemaître, a Belgian priest and professor of physics at the Catholic University of Leuven. Complementing (for Einstein) Eddington's demonstration of the weaknesses of the static model, Lemaître's paper, the importance of which Einstein now tardily recognized, showed how the laws of general relativity could be reconciled with a model of a closed expanding universe (of diminishing mass density), one that elegantly accommodated Hubble's observations of the red shift.45 When Einstein spoke in Oxford, both of these encounters would have been fresh in his mind, and they left their mark on the second lecture.

The blackboard, one of two that Einstein prepared in advance of the lecture, shows him using precisely the symbols and numerical values he had used in his Prussian Academy paper.46 In the lecture, as in the paper, he acknowledged that the figure of 108 light years that he calculated as the present radius of the universe (P) seemed low. So too did his value for the 1010 light years (t) for which, again by his calculation, the expansion had been taking place; it was lower by some orders of magnitude than contemporary astrophysicists' estimates of the age of stars. As Cormac O'Raifeartaigh and Brendan McCann have argued, it is far from certain how Einstein arrived at these figures, both of which troubled him. One possibility is that his figure for the age of the universe had its origins in a questionable result in Friedmann's paper of 1922; a discussion by Ari Belenkiy of Friedmann's calculation and Einstein's likely reliance on it points in this direction.47 In the Prussian Academy paper and in the lecture, simple numerical error may also have led Einstein astray. O'Raifeartaigh and McCann pursue this thought in attempting to reconstruct Einstein's enigmatic calculation of the radius of the universe; they conclude that his 108 light years was one-twentieth of what the calculation should have yielded.48 They also suggest that a simple numerical error may have led to a figure for the density of matter in the universe (ρ) that was two orders of magnitude greater than it should have been; instead of 10−26 g/cm3, they argue, his calculation would more correctly have led him to a figure of 1.6×10−28 g/cm3.49 That lower figure, as O'Raifeartaigh and McCann note, squared far better with the one that he came to favour shortly afterwards.

The rapid adjustments in Einstein's position during the early months of 1931 and the many uncertainties of his cosmological speculations contributed to the tentative tone that he adopted throughout the lectures, not least in the third and last, on ‘Latest developments of theory’, on 23 May. The lecture was something of a festive occasion, coming as it did immediately after the special Latin-laden degree ceremony in the university's Sheldonian Theatre in which Einstein was awarded an honorary DSc (see Figure 2).50 Yet it seems to have been the most mathematically demanding of the three. Engaging uncompromisingly with the intricacies of Riemannian geometry, Einstein again made no concession to his audience and offered, rather than certainty, an insistence on the open-endedness of his current speculations on the nature of space–time and the undiminished elusiveness of the goal of a unified field theory rooted in special relativity and applicable to both gravitational and electromagnetic phenomena. The confessional tone of the lecture carried an important message, though one largely lost on an audience struggling yet again with the twin challenges of esoteric science and language. Figure 2. Einstein with the Vice Chancellor (the Revd Frederick Homes Dudden) and Proctors outside the Sheldonian Theatre, Oxford, on the occasion of the honorary degree ceremony preceding his third and last Rhodes Memorial Lecture on 23 May 1931. © Getty Images.

Not surprisingly, the last lecture was too much for the Dean of Christ Church, the elderly biblical scholar Henry White, who to Einstein's amusement slept soundly throughout.51 The Spectator's ‘News of the week’ column went even further in admitting defeat: while welcoming the benefit of Einstein's lectures for Anglo-German relations, the writer confessed that ‘To indicate the drift of his argument is frankly beyond our power’.52 And even Sir Francis Wylie, present in his capacity as Warden of Rhodes House and Oxford Secretary to the Trustees, had to acknowledge the challenge that attendance at the lectures had entailed. In his report to the Trustees for the year 1930–1931, he managed to make light of the experience and the element of voyeurism that, but for restrictions on admission, would have brought hundreds more ‘to have a look at a famous man and then to escape, if that were possible, or, should escape prove impracticable, to fidget’.53 Wylie was amused to see a professor of mathematics slipping out after five minutes: ‘He explained that he wanted a sight of Einstein, but could not follow a lecture in German’. While press comments commonly conveyed the audience's feeling of helplessness before the twin challenge of science and language, they never departed from their prevailing tone of respect and admiration.54 Just as in 1921, when he had lectured, also in German and to the same rapturous applause, after receiving an honorary doctorate at the University of Manchester, Einstein was judged to have delivered all that could be expected of one of the most celebrated and immediately recognizable men in the world.55

Staying on

Despite the warmth with which he was received, Einstein was conscious of the mystification that many in his inevitably dwindling audiences experienced. When, after the third lecture, Wylie expressed the hope that the audience had been quiet and not fidgeted, Einstein's reply was sympathetic: ‘Ils ont bien dormi … Ils avaient le droit’.56 Slumbering listeners, though, did nothing to diminish his delight at a stay that had given him immense pleasure. Elsa, who did not accompany him, described the enthusiastic letters he had written to her back in Berlin: ‘Oxford, the calm cloisters of the college, the noble surroundings all combine to have a refreshing and calming effect on him’, she wrote to Lindemann.57 In the same vein, Einstein's letter of thanks to Lindemann spoke of ‘the wonderful weeks’ he had spent in Oxford.58 Lindemann, for his part, regarded the visit as an unqualified success at both a personal and an intellectual level. His letter of thanks for the support of the Rhodes Trustees conveyed his determination to play up the positive aspects of Einstein's stay and its benefits for Oxford:

It was not only his lectures but his presence in Oxford and his interest and help that was so beneficial. He threw himself into all the activities of Oxford science, attended the Colloquiums and meetings for discussions and proved so stimulating and thought provoking that I am sure his visit will leave a permanent mark on the progress of our subject.59

There was a measure of calculated hyperbole in Lindemann's judgement. But a cheque for the agreed £500 was duly sent on 20 May.60 Although Lothian's brief words of thanks accompanying the cheque were less than effusive, Einstein had been a gracious and appreciative visitor.

As subsequent correspondence showed, however, there remained one piece of unfinished business, a piece that mattered in Oxford, though manifestly not to Einstein. This concerned the publication of the lectures. Oxford University Press had published three of the first four sets of lectures, those by Borden, Halévy and Smuts, and at the time when Einstein received his invitation in 1930, plans for the publication of Flexner's in the USA (though not in Europe) were well advanced.61 It was understandably anticipated that Einstein would follow suit. But, despite tantalizing suggestions that he might in due course deliver a text, he never did so. An immediate stumbling block was the question of copyright, which the initial invitation had failed to address. Einstein's reluctance to grant the Press the world rights on his lectures clearly irritated R. W. Chapman, the secretary to the delegates of the Press (effectively the Press's chief executive officer). Chapman saw Einstein as a potential adornment to the OUP list, despite the demanding subject matter, and he was resolved that such financial success as a book by him was likely to have should not accrue to the author alone.

In a tetchy letter to Wylie at Rhodes House, Chapman argued that the substantial fee that Einstein had received only heightened the claims of the Rhodes Trustees, rather than Einstein himself, to be recognized as the chief beneficiaries of any publication.62 Such a contention had the makings of a matter of extreme delicacy, and Lothian (though anxious not to cause trouble) soon pitched in in the same spirit, arguing that the benefits should go to the Press itself; Einstein, after all, was already receiving ‘an ample fee’.63 Here, Chapman was open to the compromise that Einstein might be granted the foreign-language rights, though only on condition that he ceded the English rights to the Press and agreed to similar terms for his next book. A last resort in what Chapman exasperatedly referred to as ‘l'affaire Einstein’, was that Einstein might submit a reduced text of 50 pages or so.64 But even that suggestion, apparently expressed as a hope by Lindemann, yielded nothing. Chapman, long irritated by receiving no replies to his letters and cables to Einstein, was left to fume.

In making his suggestion about an alternative publication and in contrast with the tart defence of the Press's interests by Lothian and Chapman, Lindemann was maintaining the conciliatory tone that characterized his championing of Einstein at every stage, in and beyond Oxford. It was in this spirit that he associated Einstein's attitude with the fact that his ideas were ‘still in a fluid condition’.65 But his intervention did little to calm the waters. Memories and at least mild irritation had still not faded two years later, when Einstein made his last visit to Oxford. Wylie's successor as Warden of Rhodes House, C. K. (later Sir Carleton) Allen, now reported to Lothian how in the course of a social occasion Einstein had again declined to publish his lectures on the grounds that ‘he had since discovered that everything he had put forward in the Lectures was untrue’.66 Even Einstein's vague suggestion that he might write something else for the Press only stirred Allen's irony: perhaps a book on ‘My view of Hitler’ or ‘Hitler in time and space’ would sell and help to recoup the cost of the lectures. But Allen, faced with Einstein's ‘rather comic contrition’, was under no illusion.

Einstein's evasiveness with regard to publication bore the signs of both cussedness and irritation at an expectation that had never been broached in the exchanges about the terms of his visit. Yet what he said about his changing cosmological views was quite right. While remaining loyal to his abandonment of the cosmological constant and the static universe that it had served to sustain, he had soon moved on from the model that he had advanced in the 1931 lectures. In place of that model, which allowed for the possibility of a universe that existed in a state of alternate expansion and contraction, he now favoured a quite different dynamic model of the single, ‘big bang’ type, devised in collaboration with Willem de Sitter.67 In the circumstances, an updating of his ideas in popular form would have entailed far more work than the Press could reasonably have expected of him. Clearly, he had no interest in a publication of any kind, no matter what the conditions. Thereafter, the idea of a book was simply dropped.68

Despite the incipient friction with regard to the publication of the lectures, Lindemann and the Dean of Christ Church were resolved that Einstein's association with Oxford should not end with his departure for Germany on 28 May 1931. Discussions of possible ways of securing a visiting appointment that would be compatible with Einstein's many other invitations in Europe and America must already have been under way before he left, and the brief but warm letter of thanks that Einstein wrote to the Dean from the Hamburg gave every reason to believe that something might come of them.69 So too did an appreciative letter to Lindemann. But now, just a few days after arriving back in Berlin, Einstein evoked the menacing turn of events that was to cloud all future negotiations for his return to Oxford and transform the context for his visits. With German banks on the brink of collapse, unemployment escalating and the National Socialists embarking on the rise to power that they achieved less than two years later, he described his dismay at the worsening economic and political conditions of life in Germany. ‘The situation here is horrible’, he wrote. ‘All money values have disappeared, and the people are disturbed and embittered against the Government. The future lies threatening and dark.’70

Reports in the British press confirmed Einstein's pessimism and lent a new urgency to Lindemann's plans to marshal whatever help he could. By the end of June, things in Christ Church had moved fast, and on 29 June the Dean was able to make Einstein the formal offer of a college research studentship (‘studentship’ being Christ Church's unusual terminology for a ‘fellowship’71) for five years, with an annual stipend of £400, a dining allowance and the use of a set of rooms during his periods of residence.72 In return, it was ‘hoped’ (a term that carefully skirted round the suggestion of a formal requirement) that Einstein would spend ‘something like a month’ each year in Oxford in term time. Exchanges were complicated by Einstein's reluctance to do anything that might interfere with the parallel discussions between him and ‘the Mount Wilson people’, Lindemann's term for the group, centred on Hubble at Caltech, that was busy talking up the virtues of California and the telescopes and other facilities at Mount Wilson. Despite an initial request for more time in which to consider the options, Einstein soon made it clear that his preference was for Oxford, as Lindemann always thought it would be.73

Negotiations with Einstein were seldom straightforward, however, and this was no exception. While his brief, handwritten reply to the Dean conveyed his interest in the offer from Christ Church, it did not make clear that he accepted in full the conditions of the studentship, in particular concerning the time he might spend in Oxford.74 The enigmatic response provoked anxious correspondence between the Dean, Lindemann and Trevor Heaton, the college's Dr Lee's Reader in Anatomy, about how far Christ Church should press for clarification of Einstein's intentions. Lindemann, on whose influence with Einstein the plan depended, advanced his now familiar plea for flexibility, notably on the strict requirement that in each of the proposed five years Einstein should spend a month in Oxford: if Einstein chose to stay for six weeks in one year and two in the next, Lindemann argued, the college ought to be content.75 Lindemann's view that Einstein could be trusted to honour the spirit of the agreement and that he should not be unduly bound won the day. On 21 October the Governing Body unanimously elected Einstein to a research studentship on the terms that the Dean had outlined on 29 June.76 A friendly letter from the Dean to Einstein, announcing the news, and Einstein's warm letter of acceptance followed quickly.77

While the Dean's description of the Governing Body's decision as unanimous was accurate, it concealed the darker truth of a resolute dissenting voice on the margins of the college. The voice was that of the eminent Roman historian and Camden Professor of Ancient History, John George Clark Anderson. Although his appointment to the Camden chair had obliged Anderson to migrate to Brasenose College four years earlier, he had held the title of tutor and student of Christ Church from 1900 to 1927 and still regarded himself as part of the Christ Church community. As soon as the Governing Body's decision was announced, Anderson turned the full force of his patriotic indignation on the Dean. The news of Einstein's election had ‘amazed’ him.78 Especially in the current precarious financial situation, how could the college justify sending money abroad when the university was in receipt of governmental funding provided at tax-payers' expense? And if the college's new statutes, to whose drafting Anderson had contributed, did not explicitly exclude the election of foreigners to studentships, that was surely an oversight.79 In Anderson's words, ‘long tradition & practice’ had made the condition of British nationality ‘an unbroken rule’ that properly conveyed the intention, if not the letter, of the statutes now in force.

The Dean was clearly discomfited by the attack. But his insistence that the new statutes' failure to preclude the election of non-British candidates could and should be interpreted as a willingness to admit foreigners did nothing to allay Anderson's indignation.80 Nor did the benefits that the Dean believed would flow for Oxford science from even the occasional presence of ‘perhaps the greatest authority in the world on physical science’. Equally vain was the Dean's portrayal of Einstein as ‘a poor man’ who would be helped to carry on his work better by the college's ‘quite moderate pecuniary help’. A few days later, Anderson re-entered the fray with a still fuller statement of his position. Pursuing his guiding principle that ‘Charity should always begin at home’, he now protested at the allocation of funds to ‘subsidize a German'; this was not just improper, he argued, but also unwise at a time when the university was preparing to seek benefactions, from colleges among other potential donors, in support of new buildings for the hopelessly cramped Bodleian Library.81 Einstein seems to have known nothing of Anderson's xenophobic protest, and in any case the protest was soon defused by an emerging majority in favour of Einstein's election on the Governing Body.

In accordance with the terms of his studentship, Einstein arrived back in Christ Church in late April 1932, this time after a short stay in Cambridge, where he talked again with Eddington and delivered (in what appears to have been a rather improvised mixture of English and German) a Rouse Ball Lecture on his attempts to accommodate electromagnetism within the general theory.82 Although Dundas's rooms were not available on this occasion, he settled in rooms elsewhere in Tom Quad (on staircase 3) and quickly resumed the rhythm of life he had fashioned for himself in 1931. Within Christ Church, his reservations about formal dress did not prevent him from being again appreciated as a welcome companion in the Common Room. Roy Harrod, a young economics tutor at the time, found him charming and easy to get on with, although he had no sense of being in the presence of a ‘deep thinker’; Einstein, as Harrod judged him, appeared naïve where worldly matters were concerned, and his stock of rather laboured jokes was limited.83 Outside the college, his return to Oxford allowed him to resume his friendship with Helena and Margaret Deneke, the musically gifted daughters of the wealthy German-born banker Philip Maurice Deneke and Clara Overweg, a close acquaintance of Clara Schumann. Early in his stay in 1931, Einstein had visited Gunfield, the Denekes' large neo-gothic house in north Oxford, and played as second violin in a quartet of musicians assembled by Margaret. According to Margaret's account of the evening, Einstein amply held his own with Marie Soldat, Erna Schulz and Arthur Williams, all of them concert-level performers, despite a borrowed violin that sounded ‘starved and raucous’.84 This was only the first of regular musical evenings that Einstein counted among his most pleasurable social encounters during his stays in 1932 and again in 1933, as he had done in 1931.85 The relief of being able to speak German with the Denekes made Gunfield a special place for him, and in all three years he went frequently.86

When Einstein left Oxford for his country retreat at Caputh, near Potsdam in late May 1932, there was every reason to believe that his cycle of annual spring visits might run its term and even be renewed. But the foundations for a decisive change of direction had already been laid. On a visit to see Einstein in Christ Church, Abraham Flexner had broached the possibility of a permanent position at the Institute for Advanced Study, then at an advanced stage of planning in Princeton. Einstein was non-committal, but a further meeting with Flexner in Berlin later in the year took negotiations an important stage further and did so, crucially, against a background of the rapidly worsening plight of Jewish scientists in Germany. By February 1933, towards the end of another stay at Caltech, the promise of a regular (though as yet not full-time) appointment at the Institute offered a welcome escape.

By the time that Einstein returned to Christ Church for his annual visit towards the end of May 1933, his mind was on other things: not only the consequences of Hitler's consolidation of power in Germany and his own plans for work in Princeton, but also the deteriorating psychological state of his son Eduard, whom he visited in an asylum in Zurich shortly before leaving for England. Despite it all, there was time for more relaxed engagements. On 2 June he proposed the vote of thanks after Ernest Rutherford's Robert Boyle Memorial Lecture to the university's Junior Scientific Society;87 and on the following day he finally approved a chalk sketch by F. Rizzi, a ‘Tyrolese peasant artist’ (in Margaret Deneke's words) for whom the Denekes were trying to secure commissions (see Figure 3).88 Figure 3. Chalk sketch of Einstein by F. Rizzi. The sketch, dated 3 June 1933 and signed by Einstein, was made in Einstein's room in Tom Quad shortly after his arrival for the last of his three stays in Christ Church. It hangs in the Senior Common Room at Christ Church. A second sketch by Rizzi, also dating from early June, was sold at auction in 2013. Courtesy of the Dean and Fellows, Christ Church, Oxford. (Online version in colour.)

Soon, though, there were more demanding academic duties to perform. First was the prestigious Herbert Spencer Lecture, ‘On the method of theoretical physics’, which he gave in Rhodes House on 10 June. Einstein used the lecture, which he delivered and published in English, to affirm the importance of ‘pure reason’ in the physicist's quest for truth, and the role that the criterion of mathematical simplicity, rather than experimental data, played in his own continuing attempts to establish a unified field theory.89 Observation had its place at the beginning of the enquiry, and the conclusions would be subject to empirical testing. But reality, as he insisted (now as in his Rhodes Lectures in 1931, though in contrast with his earliest writings), was best expressed in the mathematical equations that he hoped would one day constitute the theory he was seeking.90

Another public assignment followed on the evening of 13 June. This was a Philip Maurice Deneke Lecture at Lady Margaret Hall, the women's college whose interests the Deneke family had done much to promote.91 Einstein delivered his lecture, on the history of atomic theories from antiquity to C. T. R. Wilson's recent work with the cloud chamber, in German. The discussion had little to do with his current work, and Einstein himself regarded it as a ‘rubbishing lecture’;92 it was never published, and press accounts of it are sketchy.93 But Margaret Deneke's account suggests a familiar enough scene, with a leading university figure, the physiologist Sir Charles Sherrington, in the chair, and an audience so large that even many of the Denekes' personal friends failed to get seats. Most familiar of all was the audience's inability to make much of what Einstein said. Although Deneke herself felt that at certain moments she had fleetingly understood the arguments, by the end she recognized that ‘It had been the Professor's magnetism that held my attention’.94

A week later, Einstein turned again to relativity, in the first George Gibson Lecture in the History of Mathematics at the University of Glasgow, followed on the next day by a ceremony in which he received an honorary degree of Doctor of Laws. Einstein used the lecture to review the path he had followed in passing from the special theory of 1905 to the general theory of 1915.95 Despite being delivered in English, the lecture was tough going for his audience of 1500 academic staff and students. It laced a core of autobiographical reminiscence with the key mathematical concepts; just as in his 1931 lectures, there were no concessions.

In Glasgow as in Oxford, Einstein fulfilled his lecturing duties to the letter. But the most enduring consequences of his month in Britain followed from his discussions with Lindemann about ways of securing refuge in British universities for displaced German colleagues, several of whom were soon to enrich work at the Clarendon Laboratory, especially in low-temperature physics and spectroscopy. Despite the imminent lifeline of an appointment in Princeton, even Einstein's own situation was not wholly secure. Since March 1933, when he had renounced his German citizenship, relinquished his passport and resigned from the Prussian Academy, he had been stateless, effectively an unemployed refugee, albeit one with influential and willing friends in Europe and America. Additional anxieties turned on his personal safety. After returning to Europe at the end of March, following another two-month stay in Pasadena, Elsa and he had taken a vacation home at Le Coq-sur-Mer on the Belgian coast. It was a tranquil spot, but in a spring marked by Nazi moves against non-Aryans the location left him vulnerable to harassment, even assassination, by German agents. With his home in Berlin looted and his property confiscated, resuming his life there was out of the question. As he had put it in an all too prescient letter to Lindemann from Belgium on 1 May, ‘I shall never see the land of my birth again’.96

The Einstein legacy

After his 1933 visit, it was to Le Coq-sur-Mer, not Berlin, that Einstein returned in late June. But he did not stay long. Towards the end of July, he was back in England, as a guest in a thatched hut at the Esher home of Commander Oliver Locker-Lampson, a colourful German-speaking Conservative Member of Parliament, friend of Churchill, and prominent campaigner against fascism whom Einstein had met in passing in Oxford. Despite a photograph of Einstein and Locker-Lampson taken ‘somewhere in Surrey’ by the Daily Herald photographer Leslie Cardew, Einstein's whereabouts were kept a carefully guarded secret.97 The visit had a strongly political cast, clouded by the worsening situation in Germany and driven by Locker-Lampson's campaign in support of Jewish victims of Nazi racial policies, following an initial admiration for Hitler. After a short stay, during which he lunched with Locker-Lampson and Churchill at Churchill's country house in Kent and met Austen Chamberlain and other advocates of rearmament, Einstein returned again to Le Coq-sur-Mer encouraged by his sense of an incipient British resolve to resist the German threat.98

He spent barely a month back in Belgium, before deciding to take up Locker-Lampson's offer of refuge from the increasingly virulent Nazi propaganda against him. Leaving Elsa to pack for the final move to America and accompanied by a Sunday Express journalist, he arrived in London on 9 September and went on to spend his last four weeks in Europe at Roughton Heath on the Norfolk coast, in modest holiday accommodation owned by Locker-Lampson. Though assiduously protected by Locker-Lampson himself and the armed guards he appointed, as well as two women secretaries (also armed, at least for a series of carefully staged photographs), Einstein was not wholly isolated.99 He received chosen visitors and was interviewed by reporters from the Daily Mail and Eastern Daily Press. He was also photographed (see Figure 4), and it was during his stay that he sat for the bronze bust of him sculpted by Jacob Epstein. A sanguine sketch and lithograph by the Danish artist Ivan Opffer may also date from this period.100 But he only emerged once in public, to speak on the looming catastrophe in Europe at a rally of the recently formed Academic Assistance Council and some related organizations in the Royal Albert Hall on 3 October.101 Figure 4. Einstein with Commander Oliver Locker-Lampson, a secretary (one of two who worked with Einstein) and a guard outside a thatched holiday property on Locker-Lampson's Norfolk estate at Roughton Heath near Cromer, September 1933. On the identity of the secretary and armed guard, see note 99. Locker-Lampson, a Conservative MP and prominent anti-Nazi, made three such properties available to Einstein and organized armed protection for him in the month before his final departure for the USA on 7 October 1933. © Science and Society Picture Library.

The Albert Hall event was given dramatic effect by rumours of an assassination plot (with a price of £1000 on Einstein's head), the consequent protective police cordon round the building and, according to Daily Herald and Daily Mail reports, a significant presence of police and supportive students inside, as well as mounted and foot police in reserve in the vicinity.102 The personal criticism of Einstein that it aroused in the Nazi-leaning Rothermere press, especially the Daily Mail and Evening News, added to the sense of danger. As a Daily Mail leading article warned a week before the event, Einstein ‘would be wise to stop this injudicious agitation in this country against the Nazi régime in Germany’: his pacifism was ‘reckless’ and ‘not at all to the taste of the public here’.103 With a day to go, the Daily Mail renewed its personal attack in an endorsement of Hitler's wisdom in wanting to rid his country of a man ‘connected with societies having Communist affiliations’.104 The Evening News was even more forthright, anticipating a lecture that would be ‘a piece of alien agitation on British soil’, designed to ‘make bad blood between this country and Germany’; in the words of its editorial on the day of the rally, ‘Intelligent and patriotic people will stay carefully away’.105 But, despite a reported infiltration of the event by a group of Oswald Mosley's Blackshirts, the evening passed off without incident.106 Before a capacity audience said to be of 10 000 and in a programme of speakers that included such prominent champions of the anti-Nazi cause as Ernest Rutherford, James Jeans, Austen Chamberlain and William Beveridge, Einstein could not have had a more glittering send-off from Europe. Four days later he was driven, in great secrecy and amid continuing fears for his safety, to Southampton, where he embarked for New York.

Once Einstein had begun his appointment in Princeton, with its handsome salary of 16 000 dollars a year, the attraction of an annual visit to Oxford quickly faded. On 21 November 1933 he wrote to Lindemann saying that he felt it improper for him to go on accepting his stipend from Christ Church, and suggesting that the money might be used to help German colleagues in need.107 In May 1934, in a letter to the Dean reaffirming his wish to decline the payment, he raised the question again. Might the funds go towards paying for ‘one or more distinguished foreign scientists’ to lecture in Oxford in his place?108 Conscious of the darkening international climate, the Dean and his colleagues assured Einstein that ‘the fullest consideration would be given to his wishes’.109 And the reallocated £400 was soon put to good use, though not quite in the way that Einstein had in mind. As the Dean reported to him, it was proposed that the classical philologist Eduard Fraenkel, recently dismissed from the University of Freiburg on account of his race, should receive £200, while the rest would be used to finance brief visits by foreign physicists.110 In the tragic circumstances, a provision that had begun, in Lindemann's mind, as a mechanism for promoting physics in the university had, as a matter of urgency, to be broadened to embrace other disciplines too. Lindemann, like Einstein, fully supported the move. So too did Erwin Schrödinger, in self-imposed exile from Berlin and at the time (in large measure thanks to Lindemann) in a temporary position at Magdalen College, mainly funded by ICI.111

Fraenkel's case soon took a happier turn with his appointment to the Corpus professorship of Latin and consequent move to Corpus Christi College only a few months after the Governing Body of Christ Church had approved its emergency assistance to him in June 1934.112 More disappointing was the failure of an approach to Max Von Laue. The approach seems to have been made, and Von Laue paid a brief visit to Oxford in late May 1934, when he stayed with the Schrödingers and almost certainly spoke to the Dean and others in Christ Church about the support that the college might be willing to offer.113 In the end, despite his declared anti-Nazi position, Von Laue decided to stay on in Germany and served as director of the Kaiser Wilhelm Institute for Physics through the Second World War.

With urgent calls for assistance accumulating, the hasty adjustments in the spring of 1934 left no doubt that the survival of the college's five-year agreement with Einstein was in jeopardy, and it was more in hope than realistic expectation that the Dean extended an invitation for him to visit Christ Church in 1935.114 Letters from Einstein in 1935 and again in 1936 predictably conveyed his regret at being unable to accept the invitations, though it was a regret tempered by his satisfaction at knowing that the funds from his research studentship were being used to support displaced scholars, now through a consolidated grant to the Academic Assistance Council.115 The correspondence made it abundantly evident that the already slender chances of Einstein's being seen again in Christ Church were diminishing. Any remaining possibility duly disappeared when the college formally and on entirely friendly terms terminated the research studentship in June 1936.116

By now, no one in Christ Church could have been surprised at the final ending of the college's association with Einstein, least of all Lindemann. In trying to engage Einstein at almost any price in his plans for science at Oxford, Lindemann had aimed high. At a time when the university's finances were in a weak, even parlous condition, he had cleverly exploited the alternative resources that were available to him through his contacts within the Rhodes Trust and Christ Church. In the circumstances, securing funding for Einstein's three brief stays must be accounted a triumph. Whether his assiduous nursing of Einstein might have yielded even greater success had it not been for the escalating consolidation of Nazi power between 1931 and 1933 remains an open question. Oxford would certainly have been a less than ideal location for his work. Only Milne was working there at a level that would have permitted serious exchanges in his areas of interest; and even in this case Milne's emerging theory of kinematic relativity was more of an alternative than a complement to general relativity. More generally, Einstein's rather ambivalent attitude to the ways of Oxford might also have been an obstacle to more enduring relations with the university. While he enjoyed the freedom and peace of his stays in Christ Church and made friends there and in the wider university community, his gratitude for the college's hospitality was always tempered by the amused detachment with which he regarded Oxford life. Still, as conditions in Germany worsened, the annual visits to Christ Church assumed the status of a refuge that Einstein could not ignore, should he need a lifeline. The refuge, though, was partial at best. And once emigration became Einstein's only recourse, what Oxford could offer was quickly eclipsed by the material and intellectual riches opening before him across the Atlantic.

Lindemann's disappointment at the way in which his longer-term aspirations had been overtaken by the tragic turn in international relations is beyond question. But Einstein's stays were not without benefit for the cause of science at Oxford. The publicity surrounding them had given encouragement to the champions of progressive reform within the university. And, as consolation for the failure of his grander plan, it now made it easier for Lindemann to turn his energies and ingenuity to the needs of other refugee scientists with problems comparable to Einstein's, though without his advantage of international celebrity. Whether or not these other refugees set down deep roots in Oxford was determined by a mixture of their temperament and the availability of permanent funding. Some of them moved on rather quickly. Fritz London, expelled from the University of Berlin, was unhappy in Oxford and, after an ICI grant expired in 1936, took a succession of short-term appointments before emigrating to the United States in 1939.117 Schrödinger, a Berlin theoretician like London, also failed to settle. An irregular domestic arrangement, involving his living openly with both his wife and his mistress, and his sense of detachment from the prevailing experimental character of Oxford physics made for uneasy relations with colleagues, and he left Oxford after two and a half years, to live a somewhat itinerant life until he finally settled in Dublin in 1940.

Yet, with Lindemann's unflagging aid and thanks to his resourcefulness in fashioning livelihoods for them in a distinctly unfavourable financial context, a distinguished group of refugees—notably Franz Simon, Kurt Mendelssohn and Nicholas Kurti in low-temperature physics (all from Breslau) and Heinrich Kuhn in spectroscopy (from Göttingen)—eventually secured permanent posts in the university and made Oxford their lasting home, remaining there as leading figures in research and teaching until well after the Second World War. In Lindemann's plan, the presence of Einstein had always had an essentially symbolic function and, in that respect, as a means of raising the profile of physics in an unfavourable university environment, it fulfilled expectations. But collectively the later refugees did far more than Einstein could ever have done in advancing Lindemann's vision for his subject. In 1919, Lindemann had arrived in what was still predominantly an arts university, with attitudes and priorities appropriate to that orientation. By the time he retired from his chair in 1956, he could look back on a transformation in which scientific research, in physics as in the other sciences, had become established as a prime function alongside the university's traditional preoccupations with teaching and scholarship in the humanities.118 Given the dismal starting point in the 1920s, that was no mean achievement.

Acknowledgements I am indebted for access to archives in the keeping of Judith Curthoys, archivist of Christ Church, Oxford; the Warden of Rhodes House and Secretary to the Rhodes Trustees, Oxford; and the Librarian and staff of Nuffield College, Oxford. In Christ Church, Brian Young and Mrs Curthoys were instrumental in providing the image of the college's Rizzi sketch of Einstein. In her capacity as director of the Einstein Papers Project at Caltech, Diana Kormos-Buchwald kindly provided the transcription of the entries in Einstein's travel diary to which I refer in note 30. It has been a special pleasure to share an interest in Einstein's time in Oxford with Andrew Robinson; the article has benefited greatly from his careful reading of two recent drafts. I am also grateful to Tony Simcock and Jonathan Bowen, who have helped to throw such light as is possible on the rescue of the blackboard after Einstein's second Rhodes Memorial Lecture (see note 46). At every stage too, the support and advice of Ben Marsden, as editor, have been invaluable. Through him, I have benefited from three outstandingly helpful referees' reports that have led me to rethink key aspects of the article.

Footnotes

Notes 1 I have generally not given specific references to standard studies of Einstein and Lindemann, the two main figures in this account. But I have drawn freely on (among other biographical sources) Ronald W. Clark, Einstein: the life and times (World Publishing Company, New York and Cleveland, 1971; Hodder & Stoughton, London, 1973); Walter Isaacson, Einstein: his life and universe (Simon & Schuster, London, 2007); Andrew Robinson (in association with The Albert Einstein Archives), Einstein: a hundred years of relativity (Princeton University Press, 2015); Roy F. Harrod, The Prof: a personal memoir of Lord Cherwell (Macmillan, London, 1959); the Earl of Birkenhead [F. E. Smith], The Prof in two worlds: the official life of Professor F. A. Lindemann, Viscount Cherwell (Collins, London, 1961); and Adrian Fort, Prof: the life of Frederick Lindemann (Jonathan Cape, London, 2003). On Einstein's stays in Oxford, an essential account is Paul W. Kent, ‘Einstein at Oxford’, in Einstein in Oxford: celebrating the centenary of the 1905 publications (ed. Steven Biller), pp. 5–11 (University of Oxford, Department of Physics, 2005). The present article extends my earlier brief study of Einstein's relations with Lindemann, published as ‘Lindemann and Einstein: the Oxford connexion’, in Relocating the history of science: essays in honor of Kostas Gavroglu (ed. Theodore Arabatzis, Jürgen Renn, and Anna Simões), pp. 23–31 (Boston Studies in the Philosophy and History of Science 312, Springer International Publishing AG, Cham, Switzerland, 2015). 2 Clifton's years as professor of experimental philosophy, from 1865 until his retirement in 1915, are discussed in Robert Fox, ‘The context and practices of Oxford physics, 1839–77’ and Graeme Gooday, ‘Robert Bellamy Clifton and the “depressing inheritance” of the Clarendon Laboratory, 1877–1919’, in Physics in Oxford: laboratories, learning, and college life, 1839–1939 (ed. Robert Fox and Graeme Gooday), pp. 24–79 and 80–118 respectively (Oxford University Press, 2005). On Lindemann's efforts to revitalize physics in the university, see Jack Morrell, Science at Oxford 1914–1939: transforming an arts university (Clarendon Press, Oxford, 1997), chapter 9. 3 Papers concerning the founding and administration of the Rhodes Memorial Lectures are in the Rhodes Trust Archive (hereafter RTA) at Rhodes House, Oxford. 4 J. R. M. Butler, Lord Lothian (Philip Kerr) 1882–1940 (Macmillan, London, 1960), esp. pp. 126–143 on Kerr's appointment and work for the Trust. 5 On the Asquith Commission, see John Prest, ‘The Asquith Commission, 1919–1922’, in The history of the University of Oxford, vol. 8 (The twentieth century) (ed. Brian Harrison), pp. 27–43 (Clarendon Press, Oxford, 1994). 6 Report of Royal Commission on Oxford and Cambridge Universities. Report. Presented to Parliament by command of His Majesty, Cmd. 1588 (His Majesty's Stationery Office, London, 1922), p. 51. 7 Memorandum, 11 June 1926, RTA, RT/2694(1). 8 Memorandum, 30 April 1926, RTA, RT/2694(1). 9 Memorandum, 9 March 1926, RTA, RT/2694(1). 10 Philip Kerr, citing the opinion of the Vice Chancellor (Joseph Wells, Warden of Wadham College) to Leo Amery, 22 June 1926, RTA, RT/2694 (1). Kerr served as secretary to the Rhodes Trust from 1925 to 1939. He became 11th Marquess of Lothian when he succeeded his cousin in the title in 1930. With respect to this later period, I refer to him as Lothian. Amery was Colonial Secretary in Stanley Baldwin's government. 11 The letter from Lindemann to his father is cited in Clark, op. cit. (note 1), pp. 144–145 (1971 edn); p. 149 (1973 edn). 12 Correspondence dating from between June and September 1927 in RTA, RT/2694(1), and the Cherwell Papers, Nuffield College, Oxford (hereafter CP), file D54. 13 Fisher to Lindemann, 23 June 1927, CP, D54/1. 14 Einstein to Haldane, RTA, RT/2694(1); and Einstein to Lindemann, undated but probably early July 1927, CP, D54/6, translation at D54/4. The words I quote are from the letter to Lindemann. The sentiment in the reply to Haldane was similar: ‘I really have not sufficient matters of real importance to submit’. 15 Einstein to Lindemann, 28 August 1927, CP, D54/5, translation at D54/4. 16 The second secretary at the German Embassy in London conveyed Einstein's agreement in a letter to Kerr on 22 September 1927, RTA, RT/2694(1). By then, Lindemann and Fisher knew that the Trustees were already making other arrangements. 17 Lindemann to Fisher, 3 September 1927, RTA, RT/2694(1); and Fisher to Lindemann, 6 and 25 September 1927, CP, D54/3 and 7. 18 Fisher to Einstein, 10 October 1927 (copy), RTA, RT/2694(1). 19 Einstein to Kerr, 24 May 1928, RTA, RT/2694(1). 20 Kerr to Borden, 15 February 1927 (copy), RTA RT/2694(1); cited in Philip Ziegler, Legacy: Cecil Rhodes, the Rhodes Trust and Rhodes scholarships (Yale University Press, New Haven and London, 2008), p. 115. 21 Abraham Flexner, Universities: American, English, German (Oxford University Press, New York, 1930); and Élie Halévy, The world crisis of 1914–1918: an interpretation (Clarendon Press, Oxford, 1930). 22 J. C. Smuts, Africa and some world problems: including the Rhodes Memorial Lectures delivered in Michaelmas Term, 1929 (Clarendon Press, Oxford, 1930). Of the book's six chapters, three were devoted to the Rhodes Lectures; the other three were based on lectures delivered elsewhere. 23 Memorandum dated 27 May 1930, RTA, RT/2694(2). Relevant correspondence is also in CP, D55. 24 Einstein to Lindemann, 12 June 1930, CP, D55/10. 25 Lothian to Lindemann, 19 June 1930, CP, D55/12. 26 Lindemann to Lothian, 4 October 1930 (copy), CP, D55/14. 27 Lothian conveyed the invitation in a letter to Einstein on 16 October 1930, expressing the hope that Einstein's acceptance ‘would contribute in no small way to the establishment of that good understanding between our two countries which Mr. Cecil Rhodes himself had at heart in establishing the German Rhodes Scholarships’; RTA, RT/2694(2). 28 Einstein to Lothian, 14 November 1930, RTA, RT/2694(2). 29 Elsa Einstein to Lindemann (from Caltech), 11 February 1931, CP, D56/1. In his reply, dated 24 February 1930 (copy at CP, D56/2), Lindemann assured Elsa that he would try to protect Einstein from ‘importunate invitations’ and ensure that he had free time, including some for sailing, ‘so that I hope he will not feel he is wasting his time here altogether’. 30 Entry from Einstein's travel diary, 1 May 1931: ‘eine ebenso bizarre wie langweilige Angelegenheit’. I am grateful to Diana Kormos-Buchwald, director of the Einstein Papers Project at Caltech, for giving me access to Helen Dukas's transcription of the entries relevant to Einstein's visit to Oxford in 1931, microfilmed from photocopies of the original diary in the Einstein Archive, Hebrew University of Jerusalem. Einstein's account is cited in Josef Eisinger, Einstein on the road (Prometheus Books, Amherst, NY, 2011), p. 124. Eisinger's book offers a documented account of the travels that Einstein undertook and commented on in his rather irregularly kept travel diaries in the 1920s and 1930s; chapters 6 and 8 cover his stays in Oxford. 31 Eisinger, op. cit. (note 30), pp. 124–125. 32 On Einstein's rejection of the idea of a shorthand transcription, see letters from Sir Francis Wylie, as Warden of Rhodes House, to H. L. Brose (of University College, Nottingham), 24 April 1931 and Kenneth Sisam (then assistant secretary at the Clarendon Press), 6 May 1931 (both copies), RTA, RT/2694A. 33 Ridley to Lindemann, 8 May 1931, CP, D60/4. 34 Lindemann to Ridley, 8 May 1931 (copy), CP, D60/5. A copy of the summary, entitled ‘The Rhodes Lectures, 1931. By Professor Albert Einstein’, is in RTA, RT/2694A. Typed drafts of the summary, some of them with pencilled corrections (seemingly in Lindemann's hand), and brief reports on the first two lectures are in CP, D59/1–17. 35 Reports on the lectures, presumably Ridley's, appeared in The Times on 11 May, 18 May and 25 May. 36 Nature127, 765 (16 May 1931); 127, 790 (23 May 1931); 127, 826–827 (30 May 1931). Oxford Magazine, 49, 688–689 (14 May 1931); 49, 719–720 (21 May 1931). This latter report for the OM, signed ‘J.G.’, was almost certainly by the young physicist James Griffiths, later president of his college, Magdalen. The OM did not report on the third lecture. 37 For an up-to-date account of the issues at stake and the relevant secondary literature, see Daniel Kennefick, ‘Three and a half principles: the origins of modern relativity theory’, in The Oxford handbook of the history of physics (ed. Jed Z. Buchwald and Robert Fox), pp. 789–813 (Oxford University Press, 2013). 38 In an extensive literature on the problems in cosmology that Einstein was addressing at the time of the lectures, see especially Helge Kragh, Cosmology and controversy: the historical development of two theories of the universe (Princeton University Press, 1996), chapters 1 and 2; Harry Nussbaumer and Lydia Bieri, Discovering the expanding universe (Cambridge University Press, 2009), chapters 6–14 and 18; Christopher Smeenk, ‘Einstein's role in the creation of relativistic cosmology’, in The Cambridge companion to Einstein (ed. Michael Janssen and Christoph Lehner), pp. 228–269 (Cambridge University Press, 2014); Helge Kragh, ‘Physics and cosmology’, in Buchwald and Fox, op. cit. (note 37), pp. 892–922 (esp. pp. 897–903); and papers cited, with respect to specific points, below. 39 Kragh, ‘Physics and cosmology’, op. cit. (note 38), p. 899. 40 On the conceptual difficulty of identifying any single discoverer of the expanding universe, see Helge Kragh and Robert W. Smith, ‘Who discovered the expanding universe?’, Hist. Sci.41, 141–162 (2003). 41 Cormac O'Raifeartaigh, Brendan McCann, Werner Nahm and Simon Mitton, ‘Einstein's steady-state theory: an abandoned model of the cosmos’, Eur. Phys. J. H.39, 353–367 (2014). 42 From the outline of the second lecture, in the printed summary cited above (note 34), p. 4. 43 A. Einstein, ‘Zum kosmologischen Problem der allgemeinen Relativitätstheorie’, Sitzber. Preuss. Akad. 235–237 (1931; read on 16 April). An English translation is appended to Cormac O'Raifeartaigh and Brendan McCann, ‘Einstein's cosmic model of 1931 revisited: an analysis and translation of a forgotten model of the universe’, Eur. Phys. J. H.39, 63–85 (2014), at 82–85. 44 Harry Nussbaumer, ‘Einstein's conversion from his static to an expanding universe’, Eur. Phys. J. H.39, 37–62 (2014). Eddington's paper had appeared in May 1930 as ‘On the instability of Einstein's spherical world’, Mon. Not. R. Astron. Soc.90, 668–678 (1929–1930). 45 Georges Lemaître, ‘Un univers homogène de masse constante et de rayon croissant, rendant compte de la vitesse radiale des nébuleuses extra-galactiques’, Ann. Soc. Sci. Brux. ser. A, 47, 49–59 (1927). 46 The blackboard was presented immediately after the lecture to the Lewis Evans Collection, now held in the Museum of the History of Science (inventory no. 44725), at the instigation of the keeper of the collection, Robert T. Gunther, and Gavin de Beer, at the time a fellow of Merton College. See Wylie's letter to Fisher, 13 May 1931, and Gunther's acknowledgement of the gift, 19 May 1931, both in RTA, RT/2694A. The MHS also has a blank blackboard (inventory no. 11714). This is thought to be the second of the two blackboards that, according to the Times report, Einstein used in his second lecture, although it might conceivably be one that he prepared for the week before. I am grateful to Jonathan Bowen for sharing his late father's account of trying to salvage a board used in the first lecture: E. J. Bowen had apparently intervened too late to prevent the erasing of what Einstein had written. 47 Ari Belenkiy, ‘“The waters I am entering no one yet has crossed”: Alexander Friedman and the origins of modern cosmology’, in Origins of the expanding universe 1912–1932 (ed. Michael J. Way and Deidre Hunter), Astr. Soc. P. 471, 71–96 (2013). 48 O'Raifeartaigh and McCann, op. cit. (note 43), pp. 73–74. 49 Ibid., p. 74. 50 The Latin oration by the Public Orator and classical scholar, Arthur Blackburne Poynton, is printed in the Oxford University Gazette61, no. 1972, 627–628 (3 June 1931) and the Oxford Magazine49, 744 (1930–1931). Also, with a German translation, at http://www.einstein-website.de/z_information/oratorrede.html (accessed 15 November 2017). For an account, with an incomplete translation in English, see Oxford Times, no. 3663 (29 May 1931), p. 17. Poynton worked valiantly to find analogies between Einstein's work and elements of Epicurean and Platonic philosophy that would have been more familiar to the audience. 51 ‘Der Dekan schlief dabei wundervoll in der ersten Reihe’: Einstein, op. cit. (note 30), 23 May 1931. 52 ‘Professor Einstein at Oxford’, The Spectator, no. 5370, 845 (30 May 1931). 53 ‘Report to the Rhodes Trustees by the Oxford secretary for the academic year 1930–1931’, typescript, RTA, RT/1296(3). 54 The tone of the report in the Oxford Times, no. 3660 (15 May 1931), p. 10, was typical, despite a complaint that no provision had been made for an interpreter. 55 Manchester Guardian, 10 June 1921. 56 ‘Report to the Rhodes Trustees’, op. cit. (note 53), f. 1. 57 Elsa Einstein to Lindemann, 11 May 1931, CP, D56/9. I quote from the English translation accompanying the letter (D56/8). Translations of a number of letters are lodged with the original German versions in the Cherwell Papers. 58 Einstein to Lindemann, 6 July 1931, CP, D56/17, translation at D56/16. 59 Lindemann to Lothian, 27 June 1931 (copy), CP, D56/13. 60 Lothian to Einstein, 20 May 1931 (copy), RTA, RT/2694(2). 61 The publication of the last Rhodes Memorial Lectures, by Hubble in 1936, left Einstein's the only ones to remain unpublished. 62 Chapman to Wylie, 6 May 1931, RTA, RT/2694(2), along with related correspondence. 63 Lothian to Wylie, 20 May 1931 (copy), RTA, RT/2694(2). 64 Mentioned in Chapman to Lothian, 10 June 1931, RTA, RT/2694(2). 65 Lindemann's comment is cited in Lothian's letter to Wylie, 20 May 1931 (see note 63). 66 Allen to Lothian, 9 June 1933, RTA, RT/2694A. 67 A. Einstein and W. de Sitter, ‘On the relation between the expansion and the mean density of the universe’, Proc. Natl Acad. Sci. USA18, 213–214 (1932). 68 In negotiations with subsequent lecturers, the Trustees' retention of the copyright was made clear from the start. Nevertheless, the remaining lectures had a chequered history. Hopes that Benedetto Croce would deliver them in 1932 foundered on advice that he was a poor lecturer and that he was unwilling to lecture in English. The Swedish economist Gustav Cassel replaced Croce for 1932, though with only moderate success: his English ‘while perfectly clear and fluent in private conversation, was almost unintelligible in public utterance’; see Oxford Secretary's report for 1931–1932, RTA, RT/1296(3), f. 6. The moderate Indian independence activist Srinivasa Sastri declined, on health grounds, to deliver the 1933 lectures, which had been intended as a bridge-building exercise between India and Europe. Thereafter, financial constraints and the difficulty of finding suitable lecturers meant that only one further series of lectures was given. This was the very successful set of three by Hubble (a former Rhodes Scholar) in 1936. Attempts to resurrect the lectures after the war came to nothing. 69 Einstein to Dean of Christ Church, 28 May 1931, Christ Church Archives (hereafter CCA), DP xx.c.1. 70 Einstein to Lindemann, 9 June 1931, CP, D56/11. Again I quote from the English translation attached to the original letter, at D56/10. 71 Throughout, I use the term ‘studentship’ exclusively in this sense. Similarly, the title of ‘student’ should be read in the Christ Church context to designate what in other colleges would be called a fellow. 72 Dean to Einstein, 29 June 1931 (draft typescript), CCA, DP xx.c.1; copy also in CP, D56/14. Correspondence in the Christ Church file shows how carefully the letter was adjusted in the light of comments submitted by Lindemann and two of his colleagues in the Christ Church Senior Common Room, the philosopher Gilbert Ryle and the ancient history tutor and Senior Censor (head of the college's academic affairs), Robert Paton Longden. Although decisive, the vote on the college's governing body in favour of the offer to Einstein (16 to 5) was not unanimous, and it was only taken after the defeat (by 16 to 10) of an amendment proposing that the decision should be postponed until Hilary Term 1932; see CCA, Christ Church Governing Body Minutes 1929–1940, 17 June 1931, f. 65. The funds were to be diverted from unused stipends for lapsed posts. 73 Einstein to Lindemann, 6 July 1931 and 15 July 1931, CP, D56/17 and 19, translations at D56/16 and 20. 74 Einstein to Dean, 13 July 1931, CCA, DP xx.c.1. 75 Lindemann to Dean, 9, 20 and 23 July 1931, CCA, DP xx.c.1. 76 CCA, Christ Church Governing Body Minutes 1929–1940, 21 October 1931, f. 70. 77 Dean to Einstein, 23 October 1931 (copy), and Einstein to Dean, 29 October 1931, CCA, DP xx.c.1. 78 Anderson to Dean, 24 October 1931, CCA, DP xx.c.1. 79 The old statutes, in force from 1881 to 1926, had made British nationality a condition of election to the competitive prize studentships that provided a traditional stepping stone on the way to a permanent college position. 80 Dean to Anderson, 24 October 1931 (copy), CCA, DP xx.c.1. 81 Anderson to Dean, 2 November 1931, CCA, DP xx.c.1. 82 Announced as ‘Die Theorie der Elektrizität im Rahmen der Allgemeinen Relativitätstheorie’ and reported on in ‘Lecture by Professor Einstein’, Cambridge Review53, no. 1310, 382 (13 May 1932). 83 Harrod, op. cit. (note 1), p. 47. Einstein even attended the occasional meeting of the Governing Body, though always (as Harrod recalled) with a supply of paper on his knee on which he surreptitiously worked through mathematical equations. 84 Margaret Deneke, ‘Professor Albert Einstein’, f. 2, typescript of chapter of Deneke's memoirs, ‘What I remember’, Deneke Papers, Box 43, Bodleian Library, Oxford. See also Einstein's travel diary, op. cit. (note 30), 11 May 1931. 85 For Margaret Deneke's engaging account of conversations and musical evenings with Einstein during his stay in 1932, see Deneke, op. cit. (note 84), ff. 6–20, and the notebook ‘Conversations with Professor Einstein’, Deneke Papers, Box 25, Bodleian Library, Oxford. 86 Fluent German speakers were not at all numerous in Oxford. Apart from the Deneke family and Lindemann, Einstein appears to have spoken German with A. S. Russell, Dr Lee's Reader in Chemistry at Christ Church, and H. G. Fiedler, the university's German-born professor of German, but probably with few others. 87 Clark, op. cit. (note 1), p. 479 (1971 edn); p. 450 (1973 edn). I am grateful to Andrew Robinson for drawing my attention to Clark's account of this event. Rutherford's lecture was published as The artificial transmutation of the elements, being the thirty-fifth Robert Boyle Lecture: delivered before the Oxford University Junior Scientific Club on 2nd June 1933 (Oxford University Press, London, 1933). 88 Deneke, op. cit. (note 84), ff. 21–25. 89 The lecture was published as On the method of theoretical physics: the Herbert Spencer Lecture delivered at Oxford 10 June 1933 (Clarendon Press, Oxford, 1933); typescript in CP, D58/5–13. It also appeared in the journal Phil. Sci.1, no. 2, 163–169 (1934), and is conveniently reproduced in Ideas and opinions by Albert Einstein (Alvin Redman Limited, London, 1954), pp. 270–276 (same pagination in Souvenir Press edition, London, 1973) and Kent, op. cit. (note 1), pp. 12–19. As a prefatory acknowledgement to the Clarendon Press edition indicates, the lecture was translated from Einstein's German by Gilbert Ryle, the classicist Denys Page and the physicist Claude Hurst, all students of Christ Church. 90 The contrast between Einstein's early indifference to considerations of mathematical simplicity and his comparatively late embrace of the ideal of the heuristic value of mathematics in the two years or so before he formulated the general theory of relativity is carefully drawn in John D. Norton, ‘“Nature is the realisation of the simplest conceivable mathematical ideas”: Einstein and the canon of mathematical simplicity’, Stud. Hist. Phil. Mod. Phys.31, 135–170 (2000). 91 The lecture, entitled ‘Einiges zur Atomistik’, was announced in the Oxford University Gazette63, 588 (8 June 1933). The fee for the lecture, which honoured the Deneke sisters' late father, was £26; see Deneke, op. cit. (note 84), ff. 12 and 26. Contrast the fee of £525 for the Herbert Spencer Lecture, to which Douglas Veale, the Registrar of the University, referred in his formal letter of invitation to Einstein, 27 April 1932 (copy), CP, D58/1. 92 Deneke, op. cit. (note 84), f. 26. 93 For example, in The Times, 14 June 1933, p. 12. 94 Deneke, op. cit. (note 84), f. 26. 95 A. Einstein, The origins of the general theory of relativity: being the first lecture on the George A. Gibson Foundation in the University of Glasgow delivered on June 20th, 1933 (Jackson, Wylie and Co., Glasgow, 1933). For an extended press account, see ‘Relativity. Professor Einstein at Glasgow. Gibson Foundation’, The Scotsman, 21 June 1933, p. 10. 96 Einstein to Lindemann, 1 May 1933, CP, D57/7, translation at D57/6. 97 Daily Herald, 25 July 1933, p. 16. 98 A photograph of Einstein and Churchill together in the garden at Chartwell on 22 July 1933 has been frequently reproduced, e.g. in Eisinger, op. cit. (note 30), facing p. 129. 99 The photograph in Figure 4 is one of several taken by Leslie Cardew on 11 September 1933, soon after Einstein's arrival at Roughton Heath. A trimmed version appeared in the Daily Herald, 12 September 1933, p. 8 (though not in all editions), and a very similar photograph, clearly taken on the same occasion, appeared in the Daily Mail on 12 September 1933, p. 12. The female figure is Marjory Howard, one of two secretaries whom Locker-Lampson provided for Einstein. The armed man is a gamekeeper on the estate, Herbert Eastoe, identified in Clement Court, ‘Man who guarded Einstein in Norfolk’, Eastern Daily Press, 22 March 1979. I am grateful to Andrew Robinson for drawing my attention to this item, which includes interesting reminiscences about Einstein's stay by local people, and to Kendra Bean of the Science and Society Picture Library for her help with the identification and dating of the Cardew photographs. 100 Joanna McManus, ‘Einstein in Britain: a portrait’, Notes Rec. R. Soc. Lond.68, 311–315 (2014). Correspondence in CCA, DP xx.c.1, indicates that, with only days to go before his departure from England, Einstein declined another request for permission to allow his portrait to be painted, by the fashionable society artist Philip de László. 101 Reported in ‘Freedom of the mind’, New Statesman and Nation6, no. 137, 404–405 (7 October 1933). For brief footage of Einstein delivering his address, see the Albert Hall website at https://www.royalalberthall.com/about-the-hall/news/2013/october/3-october-1933-albert-einstein-speaks-at-the-hall/ (accessed 27 March 2018). An extended version of the address was published by the anti-fascist Friends of Europe group as Europe's danger; Europe's hope (London, 1933). 102 ‘Rings of police guard Einstein meeting’, Daily Herald, 4 October 1933, pp. 1–2; ‘Guarding Einstein: cordon of police round the Albert Hall’, Daily Mail, 4 October 1933, p. 14. 103 ‘An unwise agitation’, Daily Mail, 26 September 1933, p. 10. 104 ‘Meddling’, Daily Mail, 2 October 1933, p. 12. 105 ‘Stop this fooling’, Evening News and Evening Mail, 3 October 1933, p. 8. 106 ‘Guarding Einstein’, op. cit. (note 102). 107 Einstein to Lindemann, 21 November 1933, CP, D57/26. 108 Einstein to Dean, 9 May 1934, CCA, DP xx.c.1. See also, in a similar spirit, Einstein to Lindemann, 22 January 1935, CP, D63/4. 109 CCA, Christ Church Governing Body Minutes 1929–1940, 23 May 1934, ff. 164–165. 110 Dean to Einstein, 31 May 1934 (copy), CCA, DP xx.c.1. 111 P. K. Hoch and E. J. Yoxen, ‘Schrödinger at Oxford: a hypothetical national cultural synthesis which failed’, Ann. Sci.44, 593–616 (1987). 112 CCA, Christ Church Governing Body Minutes 1929–1940, 13 June 1934 and 30 January 1935, ff. 167 and 190–191. 113 Dean to Einstein, 31 May 1934 (copy), CCA, DP xx.c.1. 114 Ibid. 115 Einstein to Dean, 24 June 1935 and 26 May 1936, CCA, DP xx.c.1. 116 CCA, Christ Church Governing Body Minutes 1929–1940, 29 January and 17 June 1936, ff. 230 and 246. 117 Kostas Gavroglu, Fritz London: a scientific biography (Cambridge University Press, 1995), chapter 3. In addition to the material on London, the chapter offers important broader insights into Lindemann's efforts to accommodate refugee scientists in Oxford. 118 My use of the terms ‘arts university’ and ‘transformation’ echoes Jack Morrell's compelling interpretation of Oxford science between the wars in Morrell, op. cit. (note 2).