Type O.1

Observer's compass-Experimental Model
Bowl: Brass painted black. Fill hole on side. Glazed. Expansion chamber on underside of bowl. Bowl fitted to spring plate and has four steadying arms on side. Vernier on base plate. White inside with 90 degree arc attached to side of bowl.
Card: Thin white strip marked to 8 points. Has black dome at centre. Has four arms marked 0, 1, 2, 3.
Needle: Four needles slung beneath card.
Pivot: Unsighted

Object Details

ID: ACO0341
Type: Liquid compass - aircraft
Display location: Not on display
Creator: Admiralty Compass Observatory
Date made: 1923
Credit: National Maritime Museum, Greenwich, London, Admiralty Compass Observatory
Measurements: Overall: 102 mm; Diameter: 160 mm