What is the name of the instrument for measuring atmospheric pressure?

The instrument for measuring atmospheric pressure is barometer, which is divided into mercury barometer and metal box barometer. The principle of mercury barometer is Torricelli experiment, which uses the height of mercury column to represent atmospheric pressure. There is a spring in the metal box barometer, and the change of air pressure will cause the spring to deflect, so there will be visual numbers.

Mercury barometer was invented by Moreland in 1670 and improved by German A. Sprung. It is an instrument for measuring atmospheric pressure, and its measuring principle comes from Torricelli experiment. Based on the principle that the weight of mercury in the inverted glass column in the mercury tank is balanced with the surrounding atmospheric pressure, the atmospheric pressure is expressed by the height of the mercury column. A standard atmospheric pressure is equal to 76 cm Hg.

Aneroid barometer

Empty box barometer is also called solid metal barometer. This is a portable instrument for measuring atmospheric pressure. It uses the pressure of the atmosphere on the metal empty box (the box is close to vacuum) to deform the empty box, and drives the pointer through the lever system to make the pointer point out the value of the air pressure at that time on the dial. An empty box barometer is not as accurate as a mercury barometer. Generally, stations are only used as reference instruments and are mostly used for field observation.