Columbia subject headings:
Lumber trade--Maine.
Lumbering--Maine.
Penobscot River (Me.)--History.
Harvard subject headings:
Lumber trade--Maine.
Lumbering--Maine.
Penobscot River (Me.)--History.
Princeton subject headings:
Lumber trade--Maine.
Lumbering--Maine.
Penobscot River (Me.)--History.