Agriculture--United States--Early works to 1800 1 Boundary disputes 1 Friendly Association for Regaining and Preserving Peace with the Indians by Pacific Measures 1 Germantown (Philadelphia, Pa.)--History--Colonial period, ca. 1600-1775 1 Germantown (Philadelphia, Pa.)--History--Sources 1 Indians, Treatment of--North America 1 Indians--First contact with Europeans 1 more ... Legal issues 1 Mason-Dixon Line 1 Medicine--Early works to 1800 1 Meteorology--Observations 1 Native Americans 1 Pennsylvania--Boundaries 1 Pennsylvania--History--Colonial period, ca. 1600-1775 1 Quakers--Abolition--18th century 1 Quakers--Indian Relations--18th century 1 Quakers--Pennsylvania--18th century 1 Quakers--Philadelphia--18th century 1 Slavery 1 Weather 1 less ...