Columbia subject headings:
Philadelphia (Pa.)--Economic conditions.
Philadelphia (Pa.)--Population--History--19th century.
Philadelphia (Pa.)--Social conditions.
Harvard subject headings:
Philadelphia (Pa.)--Economic conditions.
Philadelphia (Pa.)--Population--History--19th century.
Philadelphia (Pa.)--Social conditions.
Princeton subject headings:
Philadelphia (Pa.)--Economic conditions.
Philadelphia (Pa.)--Population--History--19th century.
Philadelphia (Pa.)--Social conditions.