Columbia subject headings:
Harvard subject headings:
Cambridge, John, 1748-1831--Correspondence.
Cambridge, Mary, 1754-1832--Correspondence.
Merchants--Prince Edward Island--Correspondence.
Prince Edward Island--Commerce--History--18th century--Sources.
Prince Edward Island--Commerce--History--19th century--Sources.
Princeton subject headings:
Cambridge, John, 1748-1831--Correspondence.
Cambridge, Mary, 1754-1832--Correspondence.
Merchants--Prince Edward Island--Correspondence.
Prince Edward Island--Commerce--History--18th century--Sources.
Prince Edward Island--Commerce--History--19th century--Sources.