A pair of Charles Darwin's notebooks have been reported missing from Cambridge University Library, twenty years after they were last seen.
Staff thought they'd been "mis-shelved" within its vast archives in 2000, but the matter was only reported to police last month.
The manuscripts are estimated to be worth millions of pounds.
The notebooks, which include Darwin’s seminal 1837 Tree of Life sketch, were taken out ofstorage to be photographed at the library’s photographic unit, where the work was recorded as completed in November 2000.
In a routine check in early 2001 it was found that a blue box containing the notebooks had not been returned to its proper place.
Cambridgeshire Police have been informed and their disappearance has been recorded on the national Art Loss Register for missing cultural artefacts. The library's missing notebooks have also been added to Interpol’s database of stolen artworks – Psyche.
The appeal launch on November 24 coincides with what is commonly known each year as ‘Evolution Day’ – recognising the anniversary of Darwin’s publication of On the Origin of Species on November 24, 1859, and highlighting the great naturalist's immense contribution to the history of science.
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