What is a Fortin's Barometer and how does it works?
A Fortin barometer is a cup shaped barometer with an adjustable cistern. Its working is very much similar to any other barometer. It uses atmospheric pressure to balance the weight of a column of mercury against it. So, any change in atmospheric pressure is accompanied by an immediate change in level of the mercury and can be measured in the calibrated scale. Fortin Barometer is a highly accurate and reliable barometer mostly used for meteorological measurements.
The way the Fortin barometer works is different in a sense that it uses atmospheric pressure to balance the weight of a column of mercury against it. From that, any change in the atmospheric pressure is accompanied by an immediate change in the level of the mercury and can be measured against the scale engraved on the barometer.