Columbia subject headings:
Fertility, Human--United States--History--19th century.
Migration, Internal--United States--History--19th century.
Rural population--United States--History--19th century.
United States--Economic conditions--1865-1918.
United States--Economic conditions--To 1865.
United States--Population--History--19th century.
Harvard subject headings:
Fertility, Human--United States--History--19th century.
Migration, Internal--United States--History--19th century.
Rural population--United States--History--19th century.
United States--Economic conditions--1865-1918.
United States--Economic conditions--To 1865.
United States--Population--History--19th century.
Princeton subject headings:
Fertility, Human--United States--History--19th century.
Migration, Internal--United States--History--19th century.
Rural population--United States--History--19th century.
United States--Economic conditions--1865-1918.
United States--Economic conditions--To 1865.
United States--Population--History--19th century.