Aneroid barometers don't use any liquid. Here's why:

* How Aneroid Barometers Work: Aneroid barometers rely on a sealed, flexible metal chamber called an aneroid cell. As air pressure changes, the cell expands or contracts. This movement is amplified by a system of levers and gears, which ultimately moves a needle on a calibrated dial to indicate the air pressure.

* Mercury Barometers: Mercury barometers use the weight of a column of mercury to measure air pressure.

* Alcohol Barometers: Alcohol barometers are less common but can also be used to measure air pressure.

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