An early 19th-Century brass circumferentor, unsigned, the compass with silvered dial, circle divided in 4 quadrants, the edge-bar needle with agate cap, the alidade with 2 removable sights, the circle with sights and universal ball and socket tripod mounting, and trade label John Cail Gray St. Newcastle upon Tyne, in oak case - 10¾ins. (27.3cm.) square.