Bowl- Brass painted black, filler plug at side, an expansion chamber consisting of a single corrugation is provided at the upper part of bowl. Base of bowl is glazed. Inside of bowl is painted white, fitted with four vanes projecting from side of bowl.
Card- Clear celluloid with black markings graduated to 360 degs, mounted on a white painted float. Dia. 3.2" (8cm)
Needle- Two needles enclosed in metal tubes 2.25" (5.7cm) long, mounted below float.
Pivot- Pivot stem attached to centre of glass at bottom of bowl and carries a steel pivot point which engages in jewelled pivot cup at centre of float.