R. C. Hanna, brother of Geoffrey Hanna 1945 My elder brother Geoffrey graduated in 1941 along with Brian. The two of them were awarded DSIR studentships to be taken up after the war. PhD's were to be few ! Next memory is of them sharing accommodation at ADRDE Malvern with another physicist, John Robson. What talent! Two went to Canada where John measured the half life of the neutron, Geoff, with Bruno Pontecorvo, set an upper limit to the mass of the (electron) neutrino and much more. Brian I knew again when I returned to Cambridge for a PhD. He acted as compere of the entertainments presented at the Cavendish Dinner. He urged the singers to relax."This is not Bach!" I remember a couplet from one song. "And when I've ceased contributing to knowledge “Then I can be the master of a Cambridge college". Untrue ! Considering the whole of the material presented, Professor Bragg took on the role of Queen Victoria. Brian Pippard 1945 It was towards the end of the war, and an advertisement came out that Pembroke wanted to appoint some Stokes Students for research in physics; and John Ashmead (who was my superior in Malvern) suggested I should try for this. So I went in for it, and in due course I was invited for interview. There were five or six of us in the Master’s Lodge, waiting to be interviewed by the committee, which consisted of Prof. Bragg, and Prof. Todd, and Prof. Norrish, and the Master of Pembroke, and that sort of thing—pretty formidable. We were all chatting; and everyone else was so wonderfully clever, they’d all published papers in the Royal Society Proceedings—and they were sent for, and each had half an hour or so; and my turn came, and I think they took about ten minutes or quarter of an hour, and dismissed me. I’d published nothing, because of the war. So I was somewhat surprised when I found I’d been awarded one of the three studentships. I didn’t mind—I came back to Cambridge, rooms in college and all that sort of thing, and got to work. And it was about a year later, at a garden party, old Monty Butler the Master took me aside, and said that I ought to know they’d decided to put up the pay of the other two Stokes Students… But not mine. He said, ‘For one thing, they’re married, and you’re not—you’re living in college… And the other thing is… you weren’t really on our short list, but we did need someone to look after the Chapel music.’ [As Brian was fond of saying later: ‘If you’ve got it, flaunt it!’] Robert W. Whitworth 1954 I can claim the privilege of being one of Brian's early research students even though when I last met him he knew me well but denied ever having been my supervisor. The story is that my project on liquid helium (not Brian's subject) was proposed by Donald Osborne. Donald got me started over a few weeks in the long vacation and then promptly left for East Anglia. Brian was appointed my supervisor, but after one year he went on sabbatical to the United States, and David Shoenberg took over. In those days one had to stand on one’s own feet, but I learnt a lot from Brian, most especially to concentrate on understanding a problem rather than just following the mathematics. I have done my best to emulate him in this respect, finding it both productive and very satisfying. I hope you have a very good meeting on 11th May. David Llewelyn Williams 1957 I joined the Mond laboratory in 1957 with a First in Physics from the University College of North Wales. For the first two years I shared a research room with Brian, where, as a bumbling graduate student, I could observe his consummate experimental skill. His impressive manual dexterity when handling delicate specimens was perhaps a tribute to his musical training. His experiments were meticulously planned in advance so as to obtain as much information as possible and they always finished in time for him to leave for his college duties. He somehow tolerated my own inexperience and he certainly taught me how to plan experiments. He also revealed to me a way of thinking which I had not previously encountered. Suddenly a lot of Physics made more sense to me. His book, Classical Thermodynamics, published during my time there, has also influenced many of my students. In the summer of 1967, Brian was invited to lecture at the Simon Fraser Summer School held at the emerging resort of Whistler, British Columbia. He was joined by Charlotte and the three girls and I recall an idyllic time in fine weather. Brian played on the rather marginal piano at the Inn and his lectures were pretty good too! Subsequently Brian visited us on two further occasions; I recall a small dinner featuring a large salmon at our home and also a Chinese Banquet in his honour hosted by Simon Fraser. I like to think he enjoyed his time here in Vancouver and was pleased with my progress at U.B.C. I owe Brian a debt of gratitude, both for his forbearance with my shortcomings and for the enlightenment he provided which made my success possible. I am indeed privileged to have known him. John Waldram 1959 My first sight of Brian was in the newly instituted ‘Advanced Half-Subject’ in 1957. It was the first time that any form of ‘modern physics’ had been allowed into Part I, and Brian was scheduled to deliver a course on wave mechanics: I was one of his large excited audience. He certainly impressed me. In his trademark roll- necked sweater, he lectured entirely without notes—and without error—his voice light, his presentation elegant and illuminating, a little theatrical. The following year Joe Vinen sent me from Pembroke to Clare for supervisions with Brian, and for the first supervision he requested an essay on special relativity. We’d been subjected to an amusing but muddled course on it from Teddy Bullard, and I’d been forced back to the textbooks, where I discovered four-vectors. Rather pleased with myself, I prepared my essay in this new language, and handed it in ahead of time. When the day came, my partner Andrew Bennet and I climbed the stairs to Brian’s rooms, and discovered he shared the set with a theologian, Charlie Moule: in penetrating through the sitting room to Brian’s inner sanctum, we had to run the gauntlet of ten earnest dog-collared figures beavering away on the text of the New English Bible. We found Brian at a dimly-lit table, and sat down. Brian coughed, peered at me, held up my darling essay fastidiously by one corner and enquired tartly ‘What is this?’ before letting it flutter dismissively to the table. I came later to understand how deeply he mistrusted any abstract form of mathematical formalism: he knew only too well how students can wrap themselves in elegant equations, and fail to understand what they are doing. On this occasion he wasn’t content until he knew I could explain it all, as Einstein would have approved, by imagining myself travelling on a very fast train or riding along with a photon. Andrew meanwhile kept his mouth shut, and opened his eyes ever wider as my interrogation continued. Brian’s dislike of formalism went even further. The following summer, before I started research with him, he sent me off with half a dozen papers to read at home. As soon as I glanced at them, I realised I was in trouble: they were all concerned with the new BCS theory of superconductivity, and written in second quantisation, which I’d never seen before. Useful libraries were far away. All I could do was return to Cambridge several days early, hoping to make sense of it all, and deeply fearful of failing before I’d even begun. But to my uneasy surprise, Brian never mentioned those papers again, nor did we discuss BCS theory until my third year, when I had experimental results to analyse. Much later I came to understand. The fact was, Brian hadn’t learnt second quantisation either, and had no intention of doing so—just as he’d always refused to learn to drive —but he’d thought it useful to have someone around who had. During my first year he put me up to give a seminar on the recently discovered Giaevar tunnelling in superconductors, and seeing that my seminar came out full of creation operators, he must have concluded he’d achieved his objective. What I got from him, instead, was a master-class in experimental technique. I was extremely lucky. He’d just decided he should give up working at the bench (he was spending much time planning the new Magnet Lab), and handed over to me the apparatus he’d been working with. Its experimental design was a model of effective simplicity. For instance, the frequency of the klystron source had to be stable to one part in a million over periods of up to ten minutes, which Brian achieved, not with some elaborate feedback network, but using no more than draught protection, a micrometer tuner with weight and pulley to eliminate backlash, and a stack of carefully aged high-tension batteries as power supply. (These batteries were not without hazard, as they had very little internal resistance, and the stack voltage was 2000V.
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