Complex sentence: The position as research lecturer at Perth lasted from 1937 to 1945, after which he became assistant chief geologist in the Mines Department of Victoria until 1947, and lastly senior lecturer at the University of Melbourne until 1952.
Split into simpler sentences: The position as research lecturer at Perth lasted from 1937 to 1945. After the War he became assistant chief geologist in the Mines Department of Victoria until 1947, and lastly senior lecturer at the University of Melbourne until 1952.