Liquid compass
Bowl: Grey painted brass, filler plug at top expansion chamber at rear. Inside of bowl painted white. Radium covered wire lubber line mounted under verge glass, extending from top to bottom. Mounted in a vertical metal ring dia. 8.75 ( 22.7cm) by four legs whcih have springs which act as an anti-vibration device. A bracket for securing the compass is fitted at base of ring and a compass is fitted at base of ring and a corrector magnet carrier is fitted at top.
Card: Mica strip. Black with white markings graduated to 360 degrees. Secured to high domed white painted float.
Needle: Magnets (unsighted) mounted in float.
Pivot: Brass stem secured to base of bowl. It is thought to be of the inverted type. An arm projecting from top of bowl carries a cup which engages the top of the float and prevents it from lifting off the pivot.