Columbia subject headings:
Economies of scale--United States--History--19th century.
Manufacturing industries--United States--History--19th century.
Harvard subject headings:
Economies of scale--United States--History--19th century.
Manufactures--United States--History--19th century.
Manufacturing industries--United States--History--19th century.
Princeton subject headings:
Economies of scale--United States--History--19th century.
Manufacturing industries--United States--History--19th century.