October 11, 1972 Dear Les, A couple of weeks ago I sent you a very brief note about some historical data. I was glad to see the enclosed piece by Olby that just came out in Nature, that I think puts a more accurate complexion on this kind of discussion. I am, however, putting together a memoir about the discovery of bacterial recombination, and I am trying to develop a more precise picture of the context of my early work with Francis Ryan. Harriett Taylor was another major actor, and with both of them now gone there are obvious difficulties in checking on some of the details. I have seen your very elegant account in "Genetic Organization" of the interweaving of DNA biochemistry with contemporary genetics. I would be curious now to have a more detailed account of how you first learned of and reacted to Avery's publication and the same for your then student Harriett Taylor. It is clear that I was stimulated to read Avery myself by Harriett; what is somewhat less clear in my mind is what Francis Ryan's role was at just that moment (January 1945). A few months later I had proposed to Francis to study the possibility of transforming Neurospora as a way of clearing up the biological significance of transformation. This did not work, but it led in turn to studies on the selective detection of reverse mutations and eventually of recombinants in bacteria. Another question that puzzles me more retrospectively than at the time was how it came about that Harriett worked on the lag phase of yeast for her Ph.D. dissertation. This seems to be not only a rather dull problem in general, but without any evident connection either with the general currents of genetics at that time or with the traditions of the department. So I must be missing something. Was this an experimental problem that she came to you with and demanded the privilege of pursuing as she saw fit? Or was there some other point of entry that led to it? I had some recollection that Szelig Hecht had played some role as her advisor, but that may be quite incorrect and it still does not add much clarity to understanding why this particular problem attracted her effort and attention during that time. So, my two puzzlements about Harriett are 1) how she came to learn of Avery and 2) how she came to choose her dissertation topic. With best regards, Josh