Bowl-Grey painted brass, filler plug at side, expansion chamber at base below outer cover. Inside of bowl painted white with two black lubber lines 90 degs apart. Mounted in grey painted brass gimbal ring 6.1" (15.5cm) in diameter.
Card-Dia. 3.9" (10cm) white painted, mica(?) with black marking, graduated to 1/4 points. Attached to white painted float at centre.
Needle- Two cylindrical needles can be seen mounted below card, either side of float.