Twenty-two years after a pair of notebooks filled with Charles Darwin’s early musings went missing from the Cambridge University Library, they were anonymously returned in good condition last month along with a note to the elated librarian: “Happy Easter.”

“Happy” scarcely begins to describe the reaction of Jessica Gardner, the university librarian who spearheaded an international publicity blitz in 2020 to recover the notebooks. Filled with Darwin’s scrawled handwriting and sketches from 1837, including the famous “tree of life” drawing, the notebooks recorded his thought process as he began sketching out ideas that would later develop into world-famous theories still revered and studied today, including the theory of natural selection.

On March 9, outside her office in an area of the library with no cameras, someone placed a bright pink gift bag. Gardner and her colleagues first recognized the original blue box that had been taken from the archives. Then, inside a brown envelope, they found the notebooks they had long sought inside tightly wrapped cling wrap, along with the typed note wishing her a Happy Easter.

“I still feel shaky,” she said in an interview Tuesday, when the university announced that the notebooks had been recovered. “It’s really hard to express how overjoyed I am.”

After waiting a few days — the police, who are continuing an investigation, instructed the university to wait before removing the notebooks from the plastic wrap — the university’s conservation experts delicately unsheathed them. Along with a team of experts, they looked through every page of both books, searching for damage or missing pages.

Jim Secord, the director of the university’s Darwin Correspondence Project, which has assembled the scientist’s writings, was among those who handled the notebooks, having also handled them in the 1990s before they went missing. He said it was immediately apparent that they were genuine, and that they had been kept in good condition with no missing pages.

Forgery was not a concern, he said — it would have been far too difficult to forge the several types of ink, the aged paper or the clasps on the leather binding, let alone the box it came in from the archives.

“There’s no question, I think, they are the real notebooks,” he said.

The notebooks had been held in the library’s Special Collections Strong Rooms, where the rarest and most valuable items in its collection are stored. They were taken out to be photographed in September 2000. During a routine check a month later, the small box that contained the two notebooks was found to be missing, the library said. Years of fruitless searching led the library and national experts in cultural heritage theft to conclude that they had most likely been stolen.

The return of the notebooks brings relative closure to the academics eager to bring them home to the university’s treasured collection of Darwin’s correspondence. But it has done little to settle the many mysteries that remain: how the notebooks went missing, who took them, what happened in those 22 years, and why they were returned now.

The police in Cambridgeshire said in a statement that the investigation remained open, adding that “we share the university’s delight that these priceless notebooks are now back where they belong.”

There’s no way to know what prompted someone to hand back the notebooks. But Gardner said she believed the public appeal for information in 2020, which prompted worldwide media coverage, including an article in The New York Times, could have been a factor. Perhaps someone’s conscience was pricked.

Getting the notebooks back at any point would have been a joy, but Gardner was particularly pleased that they can now be included in an exhibition starting in July. The exhibition, “Darwin in Conversation,” will come to the New York Public Library in spring 2023.

“Charles Darwin means so much to people around the world,” Gardner said. The university’s archive includes thousands of his letters, but “these two are so important,” she said.

The contents of the notebooks had long been digitized, so scholars could still study his words and images even when the books themselves were missing.

But Secord said that they contained “unparalleled insight into how an individual comes up with a discovery,” and that there was incalculable value to seeing the physical objects. Imagining Darwin scribbling in a grubby book, one that would have been readily available at stationery stores across London at the time, reflects how ordinary settings can give rise to enormous thought, he said.

“I do think they help to make the discoveries real and concrete,” he said, “and I think for us that’s really important to see.”

This article originally appeared in The New York Times.

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