Donald John Mackinnon (KES 46-49) came to King Edward’s at the age of 16 from a small school in Ullapool, Wester Ross. He left in 1949 to study Physics at University College, Southampton, joining Plessey Company research lab in 1955. In 1957 he went to work at Atomic Energy of Canada in Chalk River, Ontario, studying the effect of bombarding metals, held at liquid helium temperatures, with fast neutrons. He returned to the UK in 1961 to work for the Glasgow Health Board as a Medical Physicist, working firstly in Radiotherapy and latterly running an Equipment Advisory Service, retiring in1990. Donald passed away in December 2025.