The collaboration, which was one of the bulwarks in Wannell’s life and one of his greatest achievements, started in 1999 when Dalrymple was researching White Mughals and continued for 20 years.

Dalrymple knew he was onto a good thing after showing Wannell an 18th-century Persian traveller’s tome. “[He] opened it on a chapter describing the writer’s impressions of Calcutta, and began to translate from it as fluently as if he were reading from a modern-day newspaper.”

As a houseguest, though, Wannell could be trying. Left in charge of Dalrymple’s house in Delhi for a month, Wannell emptied both wine cellar and woodshed and appropriated various objet d’art he found appealing to augment his own quarters. On another occasion, when he was meant to be immersed in translating Persian court documents, he fell deeply in love with a dancer (whose wife was especially tolerant) and frequently absented himself from his desk.

Dalrymple writes: “Bruce was always powered by his enthusiasms and when he was fascinated with something, nothing could restrain him. Equally, when his interest ebbed, there was very little that you could do to bring him back.”

Other contributors – British journalist, Flemish artist, Kurdish percussionist et al – are united in their cogent admiration, reminiscing fondly about a man who could talk indefatigably about Sufi shrines or any similarly arcane subject, present his dinner hostess with a delicacy like Afghan mulberries together with strict instructions on how they should be served, disregard a bed to sleep on a carpet, and charm haughty ambassadors or curmudgeonly security guards into allowing him whatever he wanted.

The book’s co-editor, Barnaby Rogerson, writes amusedly about being “Wannelled” – “getting coaxed into some wonderfully romantic quest, only to realise halfway through the journey that you were being used as an unpaid chauffeur.”

As Tales makes clear, Wannell’s career path rarely trespassed on convention, to the dismay of his father, with whom he never saw eye-to-eye. He grew up in England and studied French and German at Oxford University: called upon to read out a 2,000-word essay that he’d failed to write he made it up on the spot, to the astonishment of students behind him who could see he was holding blank sheets of paper.

His interest in the Islamic world was sparked by a two-year stint teaching at Isfahan University in Iran. During the 1980s he worked for aid agencies in Pakistan and Afghanistan, parleying with warlords, succouring the needy, and seizing every opportunity to delve deeper into Islam, remaining unperturbed if the inscriptions that he wanted to inspect at a historical site lay within a battle zone.

He was always happy to drop heavy hints that he worked for foreign intelligence agencies as well. By the time he left the region in 1993, he had become a Muslim and written scripts in Pashtu and Dari for a BBC World Service series of “soaps”.

A commission to write about Islamic culture led to lengthy travels in the Middle East (generously advanced, never fulfilled, as related in Tales by publisher Nova Robinson’s contribution, “The book that never was by the most interesting man in the world”). In time he became a vastly popular guide for an upmarket tour operator, despite habitual unpunctuality and a tendency not to suffer fools gladly.

Perennially impecunious, Wannell lived for part of each year in low-rent council housing in York, Britain, and it was here that he succumbed to pancreatic cancer in January aged 67. Dalrymple ends his contribution with what could be Wannell’s epitaph: “What a world is lost when someone dies.”