Charles Darwin kidney bean in 'conservation spa'

About 400 kidney beans sent to Charles Darwin in 1857 have been carefully cleaned, ready to be added to an online archive.

Academics in Cambridge hope to finish cataloguing and digitalising thousands of items collected by the English scientist by the end of next year.

Cambridge University Library posted a video on Twitter of one dwarf kidney bean being cleaned with a polyurethane sponge and silicone-tipped shaper during "a trip to the conservation spa".

Conservation and collection care manager, Anna Johnson, said researchers would be able to access the material online, meaning items would be "preserved for much longer".