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In page Vladimir Vernadsky:

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Vernadsky participated in the First General Congress of the zemstvos, held in Petersburg on the eve of the 1905 Russian Revolution to discuss how best to pressure the government to the needs of the Russian society; became a member of the liberal Constitutional Democratic Party (KD); and served in parliament, resigning to protest the Tsar's proroguing of the Duma. He served as professor and later as vice rector of Moscow University, from which he also resigned in 1911 in protest over the government's reactionary policies[citation needed].