Alan William Halliday Pearsall, historian and museum curator: born Leeds 14 November 1925; staff, National Maritime Museum 1955-85; died London 31 March 2006.
Professor Don Schurman, Canadian doyen of British imperial marine affairs, recently wrote that, in his historical acquaintance of half a century, "the only person who understood perfectly the connection between the British Empire and the sea was Alan Pearsall". Others among four generations in the field would agree, but Pearsall's reputation was most remarkable in that it was based almost entirely on personal contact.
He wrote comparatively little, yet was a source of first and last resort in two large areas: the operational history of railways and especially railway ferries, and almost any aspect of British naval history from the 17th to the 20th century. These came together, with much else, in his 30-year career at the National Maritime Museum in Greenwich, from which he retired in 1985 as "Historian", a role of sufficient practical duties for an essentially unpractical man but really justified by his extraordinary value as adviser, teacher and scholarly oracle to colleagues at Greenwich, and to the wider specialist communities and information-seeking public that the museum serves.
Pearsall's office, and the Blackheath flat that he bought new in the early 1960s and which was never improved or repainted until almost the end of his life (no radio, television, or other modern appliances), were genizahs of apparently disordered books and paper. Their synthesis emerged from his retentive mind mostly in discussion, short notes and acknowledgements of his aid in dozens, if not hundreds, of other people's books and projects.
He belonged to some 30 learned and other specialist bodies and was active in half of them, read encyclopaedically, and for relaxation studied and annotated British and European railway timetables. About naval and shipping history, railways, industrial buildings and maritime fortifications, his knowledge was profound and, while there were subjects of which he knew and cared nothing (a non-driver, he could only identify cars by colour), he always encouraged the interests of others, recognising that advance often springs from unlikely connections.
Until his mobility decreased, Pearsall could regularly be found with like-minded enthusiasts investigating old railway, military or naval sites, while at many a conference the cry "Ask Alan" would see him rise from an inconspicuous seat and modestly cast light on some obscure issue.
The key to Pearsall's reputation, self-effacing kindness and quiet but well-developed sense of humour, lay in his background. He was born in Leeds, son of William Pearsall FRS, a pioneer of British freshwater biology, who rose to hold chairs in Botany at both Sheffield and London universities. His mother, Marjorie Williamson, was also a brilliant student of botany at Manchester, had wide cultural interests, and, after marrying William Pearsall when both were lecturers at Leeds, became a teacher and a dominating early influence.
Both parents fostered and structured their children's enthusiasms, Alan Pearsall's younger brother Ian becoming a notable research engineer until his sudden death in 1982, aged 53. However, both boys nearly died in childhood, Alan from nephritis (inflammation of the kidneys) when he was nine. Against the odds, after a week in a coma he survived, but could not return to school until he was 13. He none the less matriculated from Morecambe Grammar School in 1942 and immediately volunteered for the wartime Navy, aged 17.
After four years, latterly in the Indian Ocean, where he weathered two mutinies, he returned home a living skeleton. It took him another year to recover before he went to read History at Trinity Hall, Cambridge, and then began a PhD at London University under Professor Gerald Graham. Here, with other "buffs" who became known as the "Euston Troupe", he and his brother also extended a family passion for railways, which in 1962 resulted in his still-useful study, North Irish Channel Services.
The doctorate never materialised but Graham remained a friend and encouraged Alan Pearsall to apply for a general assistant's job at Greenwich, where he arrived in September 1955 and in the 1960s was for some years the museum's diligent and expert Curator of Manuscripts. His final historian's role was in part a response to his unpredictable health and, among other things, informed major redevelopment of the museum's historical galleries through the following decade.
His own output included specialist articles and reviews, a substantial museum pamphlet on the Second Dutch War, contributions to Society for Nautical Research and Navy Records Society publications and, most recently, revisions to obscure naval lives in the Oxford Dictionary of National Biography. As part of the London Docklands History Group, he helped preserve important buildings there before the area began to resemble Manhattan, while current climate research based on historical sources can be traced back to his advocacy of the use of weather data found in 18th-century ships' logs.
Pearsall's retirement in 1985 was marked by his investiture with the reconditely suitable but now discontinued Imperial Service Order, and (as he was told) a small private dinner at which he arrived to find 50 people waiting to honour him. Never openly astonished, he smilingly observed that a bomb dropped on the room would wipe out maritime historical scholarship at a stroke.
Happily, he was to remain engaged in it for another 20 years. His last two conversations in hospital were, appropriately, about advice to a postgraduate student on naval aspects of the Crimean War, and a specialist discussion with an old railway friend. Neither he nor his visitors anticipated that, by the next morning, he would have followed a lifetime's habit and quietly slipped away.
Pieter van der Merwe