A new exhibition at the British Library in London has gathered together magical items from around the world to shed new light on JK Rowling and her Harry Potter universe.

If your childhood (or, indeed, adulthood) was a swirling world of Avada Kedavras and Marauder’s Maps, then the magical curiosities on show at the British Library’s Harry Potter: A History of Magic are unmissable. BBC Culture takes a look at five of the exhibition’s most fascinating wizarding jewels, which typify the vast, folkloric heritage that inspired JK Rowling to create the Harry Potter series.

The phoenix

Unicorns, dragons and centaurs feature heavily in the world of Harry Potter, and while JK Rowling didn’t invent these magical beasts herself, she certainly gave age-old myths a new lease of life. She re-imagines the phoenix, a bird from Greek mythology, in her second Potter book, The Chamber of Secrets. It’s a swan-sized scarlet bird with a gold beak and talons, who endearingly looks a bit like a half-plucked Christmas turkey when it gets near its 'Burning Day' – the day the bird extinguishes and is reborn as a new, baby phoenix from its ashes.

What JK Rowling does invent is the idea that phoenix feathers can feature as constituent parts of a wizard’s wand, such as those of Harry and Lord Voldemort. A phoenix’s tears can also heal wounds, as Fawkes, Professor Dumbledore’s bird, does to Harry after he’s wounded by the Basilisk in the second book. Notoriously difficult to domesticate, they can nevertheless become a loyal pet for life; when Professor Dumbledore is killed later in the series, Fawkes sings the ‘Phoenix Lament’ – a mournful song so heartbreaking that it feels like it comes from inside the listener.

This book manuscript from the 13th Century shows a phoenix rising from its ashes; proving that JK Rowling’s predecessors were possessed of equally vivid imaginations. 

Bezoar stone

In his first-year Potions class, Harry learns an important lesson about the humble bezoar from Professor Snape: “a bezoar is a stone taken from the stomach of a goat and it will save you from most poisons.” It does indeed save one Harry Potter character – Ronald Weasley, no less – in the Half-Blood Prince after he’s poisoned by an oak-matured mead that was meant as a gift for Professor Dumbledore.

The word ‘bezoar’ comes from the Persian pād-zahr, meaning antidote. Bezoars are indigestible food masses generally found in the stomach of animals like goats and were believed to be antidotes to poison as early as the Moorish occupation of Spain. The gold around this bezoar proves how much the object must have been revered.

Tombstone of Nicolas Flamel

Nicolas Flamel is  the famous creator of the Philosopher’s Stone in the first book in the series; his discovery of the elixir for eternal life puts him at a whopping 665 years old – only beaten by his wife, Perenelle, who is 668 and with whom he lives a quiet, peaceful live in Devon. Well, at least until the stone is destroyed at the end of the book and he and his wife pass away.

Nicolas Flamel was, however, a man in real life, and this is his tombstone. A French scribe and manuscript seller from the Middle Ages, he somehow developed a posthumous reputation as an alchemist and inventor of the Philosopher’s Stone, which could turn base metal into gold and provide eternal life. “If you Google hard enough, a lot of people think that he’s still alive in India somewhere,” says Alex Lock, one of the curators of the exhibition.

A mandrake

Harry and his friends first meet mandrakes in their second year Herbology class. The root is harvested for its ability to return victims of petrification – a Dark paralysis spell – to their normal state. But these aren’t just any old roots; they’re sentient little creatures whose screams become fatal when they reach adulthood. That’s why young wizards learn to pick mandrakes when they’re still seedlings.

The mandrake root has been vastly important in folklore since ancient times, inevitably down to the fact that the roots can sometimes look a bit like shrivelled, earthy humans. People would attach a dog on a rope to the plant in order to pull it out as they were afraid of the root’s deadly scream, as is pictured in this Herbal, an encyclopaedia of plants that explained their medicinal and occult properties. Mandrakes are also well-known for their hallucinogenic and narcotic effects.

The crystal ball

Harry Potter was never a huge fan of crystal balls – he meets them as a third year student in his Divination class, taken by eccentric teacher Professor Sybill Trelawney. In this lesson, young wizards learn how to predict the future, but all Harry and Ron can see is a foggy white swirl. Harry fails again in The Order of the Phoenix to predict anything in his Divination OWL (wizarding SATs).

As well as having an actual Harry Potter-esque crystal ball to gaze into, the British Library is currently housing a rather quirky example of a crystal ball – the small, dark orb of ‘Smelly Nelly’, a British witch who wore heaps upon heaps of perfume because she thought it would appeal to the spirits that would assist her with her divination. According to an observer from the 1960s, “this small black crystal is interesting in that it is a moon crystal. That is, it is used at night to catch the reflection of the moon on its surface. The witch then gazes into the moon's mirrored reflection and gets her reading.”

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