Well, I went back to South Africa, and I set up a lab in the physiology department. I had plenty of space there. And I got a grant from the South African cancer thing to do cofactor, Phage Cofactor Genetics. And I actually did all of that there. I had very little equipment; I had a very nice girl that I could hire. Betty van Zyl, she was a Cape coloured girl, and I taught her how to pour petri dishes, and we had to do everything with quite primitive thing. But I'm very proud of that, because I actually did that paper. I actually did get recombinants for cofactor mutants, I developed methods of doing it, and I published it, and I was very proud because when I sent the manuscript to Max Delbrück, before I published it, he actually… he called together a seminar to discuss this important work. And of course this is what I took back to Cambridge. So I mean, to sit there… and I continued to work on my coding theory, and in fact by a… by 1950, early '54… by late '54, I had enough information, and I'd thought of a trick to actually prove that all overlapping triplet codes were impossible. And in fact that appeared the… I wrote an RNA Tie Club thing from South Africa that was circulated, and then Gamow was very… thought it very important, and it got published in PNAS. He submitted that paper. So that was my theoretical paper. That was… I think, if I remember, it was in '55. And that of course… it was entitled On the Impossibility of All Overlapping Triplet Codes and I'm very proud of that paper because that was done, as I say, you know, without… it was just really knowing how to divide by four, actually, which spurred… and it's a good paper, that. And I think did a lot… did a lot to clear up things. And of course at the same time Francis had come to the conclusion that the code was degenerate, that in fact we can't assign it, we can't deduce it from first principles. We just have to go and find out what it is. Which is what... what had to be done. So the… and then we had these negotiations which went backwards and forwards, and I was really wanting to get out of South Africa and this was going… and in the middle of this I got an offer of a job at Berkeley, to go there. Because I'd known Gunther Stent because of my time there. I was very… I was very torn between knowing what to do. I further got an offer from Josh Lederberg to go there, and the reason I got this, I discovered… to go to Wisconsin, and the reason I got this, I discovered is that Gunther Stent put my name on one of his grants, and Josh Lederberg saw this and decided, 'Well, if he's going to get him, I'll make a counterbid'. So I had these letters. I actually also got a letter from a company in England, saying Sir Cyril Hinshelwood had written to them. That was very nice but I was pretty desperate to go. And then finally the… the MRC came through and we arranged to leave and the reason I left then was I had come to the conclusion that I really wanted to be a scientist, and that lots of people had stayed back in South Africa and had become, you know, important people there. But the testing ground is at the centre, the personal testing ground, and you've got to go to the…  the metropolis, if I can call it that, and you've got to test yourself at the international level, because otherwise you don't know whether you're any good or not. And so that's really what it was, and… and since at that time I believed that in Africa... in South Africa the colour of my skin would always, if things changed, make me an outcast, because that's the way it looked at that time. I just decided that I would just go and do science and that's how I went back and that was… that was a conscious decision.

[Q] But you were in correspondence with Francis during this period?

Over this period, yes. I… this correspondence exists of course and a lot of it is in Judson's book, and in this we… the idea was we would do the gene protein problem. We would tackle this problem in bacteriophage, and so a lab would be set up and… and in fact this… this… so this was the idea: we'd all get together and we'd do this work. And people had arranged to come from America. Seymour Benzer was going to come, George Streisinger was going to come, and in the Cavendish, this was where we'd do it.