I cannot claim to have known Jon well, but we did go back a long way. He was in the year below me at school. We met again as graduate students at Oxford, when I volunteereed for an experiment he turned out to be running. I will always be grateful to him for organising the soul disco in the upstairs room at the 'Cape of Good Hope'. It really was heaven's disco; pounding 60s and 70s soul both classic and obscure, a dark and sweaty room full of dancers, and a good chance of meeting friends. Anyone who has done a research degree knows what a lonely and miserable existence it can be. I remember Jon's event as the highlight of the week.
Jon was obviously a marvelous colleague and devoted husband and father. My thoughts are with all who were close to him.