📖 An era of ink and genius: mechanical barometers, also known as aneroid bartenders, are tools used to measure atmospheric pressure without the use of liquids. Invented in 1843 by the French Lucien Vidi, these devices offer a practical and portable alternative to mercury barometers. The heart of a mechanical barometer is a sealed metal capsule, called aeroid capsule, inside which a partial void has been created. The variations of external atmospheric pressure cause the deformation of the capsule: when the pressure increases, the capsule compresses; When it decreases, he expands. These movements are amplified by a system of levers and gears that move a needle on a ranking dial, thus indicating the value of the atmospheric pressure. Unlike mercury bars, mechanical barometers do not contain.
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