Disadvantage of a mercury barometer:
1. A major disadvantage of the mercury barometer is its bulk shape and fragile glass tube.
2. The mercury levels may be difficult to read under unsteady conditions, as on board a ship at sea.
1. Aneroid barometer does not need a mercury column, so it is compact. It is easier to handle.
2. It is easier to read, as the measurements are calibrate minutely.
3. It is highly sensitive and can be used to record small changes in pressure