Darwin Correspondence Project

American teacher. Taught at a school in Philadelphia, circa 1821–35. Member of the House of Representatives, 1835–6, 1841–7. Assistant to the state geologist in the geological survey of Pennsylvania, 1837–41. Professor of geology, University of Pennsylvania. Secretary of the American Philosophical Society, 1848–74; treasurer, 1851–74. Member, City Council of Philadelphia, 1856–62.