This is a wooden compass with a paper card. Thomas Greenough (1710-1785) was a mathematical instrument maker in Boston who specialized in backstaffs and other instruments for nautical use. It is thus not surprising that the central image on this card (which is terribly worn and faded) depicts a man on shore sighting with a backstaff and a two-masted ship at sea. Joseph Frye (1711-1794), the original owner of this compass, probably acquired it in 1762, at the time that the Massachusetts General Court
granted him a township in Maine. The town of Fryeburg was incorporated in 1777. The Museum also has the manuscript "Tables Useful in Surveying Land, made and presented by Joseph Frye to his son, Joseph Frye, Jr., November 18, A.D. 1783."
Ref: Silvio A. Bedini, Early American Scientific Instruments and Their Makers (Washington, D.C., 1964), pp. 85-92.