Following his graduation from Merton College, Oxford, with a degree in English language and literature he took on the post of assistant librarian at the University of Leeds in 1938.
[1] Except for a stint in the Royal Army Medical Corps during the Second World War from 1940–46,[1] Masson remained a librarian for the rest of his working life.
Following his demobilisation he took on the role of curator of special collections at Liverpool and married his wife, Olive Newton, in 1950 before returning to Leeds in 1956 to become curator of the Brotherton collection, an assemblage of (mostly) English literature including many rare books and manuscripts bequeathed to the University by Lord Brotherton of Wakefield on his death in 1930.
Traveller's Rest, published in 1965 in New Worlds magazine, introduced Masson to his audience; a study in the uselessness of war focusing on a soldier's perceptions of reality in combat, perhaps influenced by his own experiences twenty years earlier.
These were included in the 2003 re-issue of Caltraps.... Masson also wrote several articles on the functions and effects of phonetic sound-patterning in poetry between 1951 and 1991.