Columbia subject headings:
Harvard subject headings:
Inland water transportation--United States--History.
Merchant marine--United States--History
Merchant ships--United States--History.
Shipping--United States--History
United States. Navy--History.
Princeton subject headings:
Inland water transportation--United States--History.
Merchant marine--United States--History.
Merchant ships--United States--History.
Shipping--United States--History.
United States. Navy--History.