18thcentury alaska bering biography discoveriesingeography discoveryandexploration explorers history kamchatskai͡aėkspedit͡sii͡a(2nd:1733-1743) kamchatskai͡aėkspedit͡sii͡a(2nd:1733-1744) kamchatskai︠a︡ėkspedit︠s︡ii︠a︡(1st:1725-1730) kamchatskai︠a︡ėkspedit︠s︡ii︠a︡(2nd:1733-1743) kamchatskai︠a︡ėkspedit︠s︡ii︠a︡(2nd:1733-1744) russia russian russians scientificexpeditions travelbering vitusjonassen камчатскаяэкспедиция(2nd:1733-1743) камчатскаяэкспедиция(2nd:1733-1744)