Bowl-Black painted brass, filler plug at side, glazed bottom, annular bubble trap below verge ring. A card lifter is fitted to side of bowl, operated by a lever and spring, it passes through a gland in lower edge of bowl where a metal rod is connected to pivot stem which can be raised to lift card off pivot. Inside of bowl painted silver, four black painted lubber lines are carried on metal strips attached to side; the lubber lines are continued across underside of verge glass in the form of a cross. Verge ring is graduated to 360 degs. Verge glass carries a central spigot to acommodate an azimuth sight and which also has a claw to adjust pointer on card. Azimuth sight has two hinged arms; 7.1" (18cm) and 5.1" (13cm) long-the shorter has a slit sight and the other a slit with thread. Mounted in black painted brass gimbal ring 11.22 (28.5cm) diameter.
Card- Dia. 8.8" (20cm) white painted mica(?) with black markings, graduated to 32 points and to 260 degs. Fitted with a metal steering pointer to indicate course to be steered whcih can be turned by a claw operated by a knob attached to spigot at centre of verge glass. Large unpainted float mounted below card.
Pivot-~Unsighted but stem can be seen attached to bridge mounted across bottom of bowl.