A hand-written draft of the Sorting Hat’s song by JK Rowling has been added to an exhibition of previously unseen artefacts from the Harry Potter stories.

The collection, which will go on display at the British Library in London, marks the 20th anniversary of the series’ first book, Harry Potter And The Philosopher’s Stone.

The exhibition features early drafts handwritten by JK Rowling.The exhibition features early drafts handwritten by JK Rowling (JK Rowling/PA)

The poem, which featured in the book as the boy wizard arrived at Hogwarts school for the first time, reads:

“Oh, you may not think I’m pretty

“But don’t judge on what you see

“I’ll eat myself if you can find

“A smarter hat that me.”

Harry Potter: A History Of Magic promises to treat visitors to a range of original drafts and drawings by both Rowling and illustrator Jim Kay for the first time.

The exhibition features real examples of ancient witchcraft.The exhibition features real examples of ancient witchcraft (The British Library Board/PA)

Julian Harrison, head curator at the British Library, said of the new addition: “It’s always so thrilling to see an author’s original draft in their own handwriting, and JK Rowling’s draft of the Sorting Hat song is no exception.

“It’s integral to the Harry Potter stories, and it’s amazing to see how it was originally written and amended.

“We hope this provides an exciting taster of what kind of material visitors can expect to see in our exhibition.’

The display, created with Bloomsbury publishers, will also feature ancient texts and objects about magical folklore from the library’s archives that lent inspiration to the world-famous stories.

Among them are a 15th century depiction of a potions class and the 16th century Ripley Scroll that explains how to create a Philosopher’s Stone, as well as hand-coloured pictures of dragons, unicorns and a phoenix rising from the flames.

Tickets for the exhibition, which opens on October 20 until February 28 next year, will be available online only from 12 noon on April 3.