Dated 18th century Azimuth Compass
A wooden cased compass with stand made during the last quarter of the 18th century by M.J.P. Maya of Rio de Janiero. The bottom of the compass card is dated 1779. The compass contains a decorative painted card with very fine and delicate details of compass rose cardinals and sub cardinal points as well as a 360 degree scale(divided into 4 scales of 0-90 degrees). The needle is mounted on a sharp pivot at the center of the case as to permit the needle to rotate freely in the horizontal plane. On top of the compass housing are two upright sight vanes on either side. Each vane has a vertical slit, down the center. The sight vanes were moved until they were aligned with the sun, the moon, or the pole star. In this way a reading of the azimuth North could be compared with the magnetic north to maximize accuracy. The compass bowl has remnants of old red paint and the gimbal ring retains its brass/bronze coloring. The compass measures 6 1/4″ in diameter. The box is 11 1/2″ square.