 Oliphant retired as Professor of Particle Physics in 1964 , and was appointed Professor of Ionised Gases . In this chair he produced his first research papers since the 1930s . He was appointed Professor Emeritus in 1967 . He was invited by the premier , Don Dunstan , to become the Governor of South Australia , a position he held from 1971 to 1976 . During this period , he caused great concern to Dunstan when he strongly supported the decision of the Governor @-@ General , Sir John Kerr , in the 1975 Australian constitutional crisis . 
