There was a report by Rossi who was in contact with Italian physicists. Italian... three Italian physicists working under quite difficult conditions during the German occupation had managed to investigate the interaction of cosmic ray mesons with atomic nuclei. And they found to their great surprise that negative cosmic ray mesons were not captured by the nucleus, and by all theoretical expectation they should have been because the meson had been invented in order to... to explain the very strong interaction inside the nucleus. Well... so this was a puzzle which took up quite some time at the Shelter Island conference, and several people had ideas about it, most of them silly. The good idea came from Marshak, my former student and now a professor at Rochester. Marshak said 'Well, maybe there are two mesons. Maybe there's a cosmic ray meson, and there is another which makes the nuclear forces and maybe the Yukawa meson is produced when cosmic rays come in to the atmosphere and hit a nucleus, they make a Yukawa meson and maybe that then decays into the meson which we actually see.' That was an ingenious idea, and a little later Marshak and I jointly wrote a paper about it.