Twenty years after the publication of the first of J.K. Rowling’s books about the boy who went to Hogwarts School of Witchcraft and Wizardry, the British Library is celebrating with a major exhibition which brings together an impressive array of objects and texts to explore some of the folklore, traditions, and magical histories in the world of Harry Potter.

There are mandrakes and bezoar stones, dragon eggs, mermaids, and mirrors. From the British Library’s own chamber of secrets, treasures brought out for the exhibition include a seventeenth-century manuscript that once belonged to Gabriel Harvey, which outlines ‘Howe experyments to be invysible must bee preparedd’. There is also the thirteenth-century Liber Medicinalis, containing the first documented use of ‘Abracadabra’, with an explanation of how to write the word repeatedly on successive lines, omitting one more letter each time, to create a cone-shaped amulet that could be worn around the neck to drive out fever. Readers of the Potter series will recall that magical books in Hogwarts are often emphatically material – perhaps furry, or noisy, or even violent things which might leak ink, require stroking, or at least must be handled with care. They would not be out of place alongside these intriguing testaments to ancient magical traditions chosen from the British Library’s collections.

But in some ways the most absorbing exhibits are the personal contributions from J.K. Rowling herself. There are handwritten drafts of chapters in biro on very ordinary A4 paper; typed pages of drafts with revisions by Rowling and her editor; and incredibly detailed charts that were part of her planning, showing how she managed the challenging task of weaving together very complex plots over seven books. There is a first edition paperback copy of Harry Potter and the Philosopher’s Stone annotated by Rowling, again in biro pen, with a mixture of charming illustrations and reflections on her experience of writing and rewriting. After Hermione’s encounter with a troll, for example, Rowling fills the blank space at the end of the chapter with a picture of some scissors and an unfurling ribbon, commenting: ‘This was the cut I refused to make – my editor wanted to lose the whole troll-fighting scene. I’m glad I resisted’. These material traces offer a magical glimpse into the processes involved in one of the biggest publication successes of the twentieth century.