I had an experiment which Francis dissuaded me from doing, which was to see if nematode genes would work in bacteria. I had been very impressed by our steam engineering approaches, namely that if you bung DNA together hard enough it will... it will work. And I knew that Bacillus subtilis was an organism that could accept DNA. And therefore I said, well, if I get a mutant of Bacillus subtilis in let us say, a glycolytic enzyme, molecular biology had shown us that the glycolytic enzymes were the same throughout the whole of nature, so that function would be retained. So triosephosphate isomerase from me and E. coli [Escherichia coli] and yeast and lobsters is all a very similar protein. Therefore I argued very naively that if I could get... if I could get a mutant of Bacillus subtilis, and I could make it so it wouldn't revert itself, which is make double mutants, then I could take nematode DNA and see if I could restore the gene to Bacillus subtilis. And... and then if I got that in, then I'd have a piece there, then I could climb in with others, because this would have to be brute force, the others would be by genetic homology. So I had a whole scheme then worked out in about 1972/73 to do this transformation experiment. What I calculated is how many events. Now, this concept of event is quite interesting. I invented a unit for it called an Av.