Bowl-Dia. 6.7" (17cm) Black painted wooden bowl, glazed, detachable wooden base. Inside of bowl painted white with black lubber line painted on side. Mounted in a brass gimbal ring 7.9" (20cm) dia. which is attached within a wooden box 9.45 x 9.45 x 5.9" (24 x 24 x 15cm) with sliding wooden lid with brass handle at top.
Card-Dia. 5.1" (13cm) White paper card with black markings. Graduated to 32 points with decorated East point and quadrantally in degrees from East & West points. Brass pivot cap mounted at centre.