Columbia subject headings:
Essex County (Mass.)--History--Periodicals.
Essex Institute--Periodicals.
Science--Periodicals.
Harvard subject headings:
Essex County (Mass.)--History--Periodicals.
Essex Institute--Periodicals.
Science--Periodicals
Princeton subject headings:
Essex County (Mass.)--History--Periodicals.
Essex Institute--Periodicals.
Periodicals.
Science--Periodicals.