There are few greater pleasures than the rediscovery of a book that you think you have lost. By which I don't mean that copy of Great Expectations you were certain was on the bedside table and now has mysteriously vanished: no, I mean a book you know you read, know you loved, and knew at the time that everything about it - title, author, tiniest detail, grandest theme - would stay with you for ever and ever and ever. But ... wait. Suddenly all you can remember is one telling detail, and the rest has flown the coop. There's that scene with the fork, the radio and the bolt of lightning, but nothing else. There's a tall woman with bright red hair and a limp, but farther than that you can't get. It's maddening. What on earth is a reader to do?

Turn to BookSleuth , that's what. Last week, readers may recall, author Alan Garner revealed he had, for years, suffered from just such a loss. He could recall a boy able to magically descend through the staircase in a pillar box to a garden where a girl could be found; he could recall “a wise but erratic old gentleman”. He had been through decades of anguish, he told us, as a result of his inability to recollect anything more.

I'm pleased to say he is anguished no more. One of our readers put a query in on his behalf on the aforementioned Booksleuth, a feature you'll find if you head to abebooks.com, one of the good websites for sourcing out-of-print books. There you'll find souls who ask such things as: “I'm looking for the name of a humorous fictional book about a college professor that winds up with his own personal cannon, one that fires oil cans filled with concrete. Any help would be appreciated.” There's a woman who recalls a book in which a girl marries an Alaskan ship captain; someone wants to find a ghost story about a house that can't be slept in. Have a browse - perhaps you can help. Alan Garner got his answer because a kind soul wondered whether it wasn't Marion St John Webb's “Mr Papingay” books he was after . . . yes, came the delighted answer - exactly those. “My yearning for a pillar box and a girl and an old gentleman is resolved and a 64-year itch has gone,” Garner says. “Now I may rest. Thank you!”

Happy endings are rare enough in life, I find - even rarer than they are in novels. It's immensely satisfying when one gets a glimpse that, as the stories sometimes tell us, they might just be possible.

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