Only appearing in Who's Who as the husband of the composer Dame Elizabeth Maconchy, he served for nearly 40 years as librarian of the Royal College of Surgeons, in London (1929-68). His many specialist publications included a bio-bibliography of the vaccination pioneer Edward Jenner (1951), Betsy Sheridan's Journal (1960, reissued 1986), a catalogue of Jonathan Swift's library (1988) and a study of the writings of Nehemiah Grew (1990). He also translated the Latin works of Sir Thomas Browne for Sir Geoffrey Keynes's complete edition.
Billy LeFanu was descended from a Huguenot family who had escaped from Catholic persecution in France to tolerant Dublin. Though always feeling himself Irish, he was one of the first members of his family to work in England. After Eton and King's College, Cambridge, and a brief spell of teaching he became assistant librarian of the Hellenic Society in 1927, and moved to the Royal College of Surgeons two years later. Under the auspices of the Rockefeller Foundation he undertook in 1937 a survey of London's medical libraries, and proposed co-operative reorganisation.
The surgeons' college with its library was destroyed in the Blitz, but LeFanu had evacuated the books and, in addition to his work as an air raid warden and member of the Home Guard, organised the supply of periodicals to Army and Navy hospitals. While the college was rising from the ashes he threw himself into the development of medical libraries in the United Kingdom and North America. He was chairman of the meeting of the International Congress of Medical Librarians in London in 1953, and vice-president of the meeting in Washington in 1963. He gave valuable assistance to medical libraries at the Royal College of Nursing, the Osler Library at McGill University and the Royal College of Physicians in Dublin, and was an examiner and lecturer at University College London School of Librarians. Never robust, this slim, smiling figure was always at hand with shrewd experienced advice based on a rare knowledge of books, scientific and classical, in English and other European languages.
His quiet satisfaction in his Huguenot ancestry led him to become President of the Huguenot Society (1956-59) and Chairman of its publications committee (1959-79). He was proud of a portrait of one of his ancestors, who as a small child had escaped hidden in an apple barrel. His breadth of interests gave him many admirers. As a member of the Linnaean Society he was a keen naturalist and at his Essex home planted an orchard with an unusual variety of fruit trees.
Sharing Dean Swift's criticism of the treatment of the poor, LeFanu was a radical in his politics, questioning inequalities of wealth in contemporary Britain. In matters of faith he shared the tolerant humanist attitudes contained in Sir Thomas Browne's Religio Medici. He valued the ministrations of the parish of Eaton, in Norwich, and during our conversations in his last weeks he told me, with a whimsical smile, that his mind was not acute enough to grasp all the doctrines involved in Holy Communion.
He was devoted to his wife Elizabeth Maconchy and her career, delighting in her prolific musical achievements and sharing her admiration for Vaughan Williams, and was always at hand to assist her in every way. She predeceased him by five months, and he was buried beside her, attended by the care and affection of his children and grandchildren.
William Richard LeFanu, librarian: born Bray, Co Wicklow 9 July 1904; married 1930 Elizabeth Maconchy (died 1994; two daughters); died Norwich 1 April 1995.