One of Northern Ireland's most distinguished musicians, he was born in Hillsborough, County Down, and went on to conduct both the Halle and London Symphony orchestras.
The hat forms part of the Hamilton Harty Papers in the Special Collections at Queen's University Belfast, where it is held among annotated conducting scores, arrangements of Handel and Berlioz, letters, photographs and a non-collapsible top hat.
Other important material held at Queen's includes the near-intact private library of antiquarian Thomas Percy (1729-1811); the manuscripts, notebooks and correspondence of folk music collector Edward Bunting (1773-1843), the first scholar to record the repertoire of traditional Irish harpists; and the notebook of Irish anecdotes, reports on seances and other papers produced by cousins and literary partners Edith Somerville (1858-1949) and Violet Martin (1862-1915), who published as "Somerville and Ross".
Send suggestions for this series on the treasures, oddities and curiosities owned by universities across the world to: matthew.reisz@tsleducation.com.