Bowl - Black painted brass, filler plug at side, expansion chamber at base. Bottom of bowl glazed. Base of bowl fitted with a metal collar carrying two lead weights 180 degs apart. The verge ring has a raised inner edge which is graduated to 360 degs. The verge glass has a black portion at centre 4.25" diameter. At centre of verge glass is a raised glass disc 1.25" in diameter for locating an azimuth sight. Inside of bowl painted black fitted with a bracket on fore side painted white with a black painted lubber line. A white wire lubber line is attached to aft side. Mounted in a black painted gimbal ring 13" (33cm) in diameter. On upper edge of ring are four raised and curved lead weights, placed one on each side of pivot points.
Card - Diameter 6.5" (16.5cm) Mica (?) ring 0.75" (1.9cm0 wide. White with black markings graduated to 32 points abd quadrantally in degrees. N point indicated by red triangle with wings either side. Attached to pivot point by wire framework of eight struts.
Needle -Two needles approx. 2.5" long of circular section mounted below card.
Pivot - Unsighted but stem can be seen attached to bridge mounted across bottom of bowl.