Compass card

Dry compass

Card: Mica covered with paper, white with black markings, N point indicated by a five-pointed star, graduated quadrantally in degrees and to 1/2 points. At centre of card is a hole 0.5" (1.3 cm) dia to accommodate pivot cup. Brass balancing weights secured at E & W points.

Needle: A single flat bar needle 5.5" (14.0 cm) long with pointed ends and expanded centre.

Pivot: Cone shaped brass pivot cup with jewel at top secured through centre of needle.

Object Details

ID: ACO0869
Type: Compass card
Display location: Not on display
Creator: Froment
Date made: circa 1825
Credit: National Maritime Museum, Greenwich, London, Admiralty Compass Observatory
Measurements: Overall: 15 mm; Diameter: 140 mm