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Mass and Moles

Deep underground in a vault beneath Paris lives the most important lump of metal in the world - Le Grand K. Created in the 19th century, it's the world's master kilogramme, the weight on which every other weight is based. But there is a problem with Le Grand K - it is losing weight. Professor Marcus du Sautoy explores the history of this strange object and the astonishing modern day race to replace it.

Release date:

1 hour

Last on

Tue 11 Aug 2015 23:30


Role Contributor
PresenterMarcus du Sautoy
DirectorMike Cunliffe
ProducerMark Woodward