Renaissance tools, such as forceps and teeth extractors, look pretty much the same today.

“We had a fabulous set of surgeon tools from the Atocha just sitting in a humble case, where they were the last stride before people step into the treasure gallery,” Kendrick said. “I bet people zoomed past them to get to the bling and never even noticed them.”

Three times a week, Harry Potter went to the greenhouses behind the castle to study herbiology, learning to take care of strange plants and fungi. At the exhibit, barrels that say “lift and sniff” are filled with fennel, rosemary and cumin.

It was believed that fennel seeds built confidence and courage when hung over doorways to ward off evil spirits and keep away ghosts. Rosemary placed under a pillow was thought to repel evil spirits and bad dreams. Cumin seeds thrown at a wedding ceremony would ensure the bride and groom a happy life and keep chickens — and husbands — from wandering.

Mandrakes and frogs

To tell the story, the museum put together glass cases filled with old corked bottles, labeled horned slugs, frog parts, sands of time, jellyfish stingers and the elixir of life.

In Harry Potter’s second year, he learned how mandrakes, real plants studied by botanists, were the key ingredient of a curative potion for his severely injured classmates.

When mandrake roots are dug up, the plant screams and kills all who hear it. That’s why the kids wore earmuffs in the book.

Mandrakes, associated with medicinal and magical properties, were included in two Bible references and four references in the literary works of William Shakespeare. Possessing mandrakes was one of the charges brought against Joan of Arc in the 1431 trial that resulted in her being burned at the stake.

“These roots do exist,” one museum worker said of the manmade mandrakes in the exhibit. “And the roots do sort of resemble a human figure.”

Before changing the battery in one of the “mandrakes,” the worker said: “Cover your ears.”

The crown of the exhibit is the golden goblet, recovered from the Atocha. It would have held a bezoar stone, which was thought to be a universal antidote against any poison.

Potter uses such a stone to save Ron Weasley from poisoned mead.

The exhibit even found a way to incorporate a large heavy cannon, which was used for the previous pirate exhibit and would have been problematic to move. It was part of the ceremony to open the Quidditch World Cup (basically soccer on brooms).

“I worried when we were working on the exhibit that we might not have the right balance,” Kendrick said. “I didn’t want it to be too cheesy or too much of the kids and not enough of the history. I think we got it right. And I hope people enjoy it as much as we enjoyed doing it.”

A previous version of this article misstated the century of the artifacts on display.