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When Mendeleev first announced the periodic table to the Russian Chemical Society in 1869, it included sixty-three elements.

My friends said Mendeleev wasn’t handing its patrons masks the week before.

As scientists celebrated Dmitri Mendeleev’s enduring array of chemical elements this year, some also wondered whether there might be a better way to organize the stuff of the universe.

Many historians date the invention of the periodic table to the publication, a hundred and fifty years ago, of a textbook by the Russian chemist Dmitri I. Mendeleev.

Central to those efforts was investing heavily in precision metrology; the tsar found eager and skilful natural scientists such as Mendeleev to help7.