Aneroid Barometer consists of two flat, highly evacuated metal cans which deform in response to change in air pressure. This deformation is indicated by a pointer. The pointer mechanism and metal cans are placed behind the glass cover for easy observation. The action caused by the change in air pressure can be demonstrated by pumping the attached rubber ball.
100mm Dial graduated 28 to 31 inches of Mercury and 960-1060 millibars with plated blazel cover glass and index plastic base. Approximately 16cm dia