1770-1838 1774-1809 1805-1866 1805-1885 approximately1758-approximately1839 bernard biography clark congresses discoveryandexploration economicdevelopment explorers familysacagawea fiction france frontierandpioneerlife history indianinterpreters jean-baptiste lewis lewisandclarkexpedition(1804-1806) meriwether moralandethicalaspects personalism pioneers politicalecology sacagawea shoshoniindians shoshoniwomen socialscientists technologyandcivilization toussaint trappers william