Complex sentence: From 1946 he was also a Fellow of the Royal Society of Edinburgh (his proposers including C. T. R. Wilson), was President of that Society from 1967 to 1970 and won their Makdougall-Brisbane Prize for 1968-70.
Split into simpler sentences: From 1946 he was also a Fellow of the Royal Society of Edinburgh (his proposers including C. T. R. Wilson) and was President of that Society from 1967 to 1970. Feather won the Makdougall Brisbane Prize of the Royal Society of Edinburgh for 1968-70.