
A diagram of the Torricelli barometer, showing Evangelista Torricelli (1644) upending a fully-filled tube of mercury into a larger bowl of mercury, the height of the mercury "column", below the void formed at the top, being the measure of atmospheric press. [1]

A diagram of the Torricelli barometer, showing Evangelista Torricelli (1644) upending a fully-filled tube of mercury into a larger bowl of mercury, the height of the mercury "column", below the void formed at the top, being the measure of atmospheric press. [1]

In barometers, Torricelli barometer is a device that measures atmospheric pressure, made by talking a long tube of mercury, filled to the top, then ceiled with a thumb, then upended into a larger bowl of mercury, after which “gap” or void is formed in the top of the tube, which varies with the pressure or weight of the height of the atmosphere.

Overview
In 1644, Evangelista Torricelli constructed the device, which was generally based on the Berti water column barometer (c.1639) (see: Berti vacuum experiment), itself stimulated into inception from debates over the Galileo vacuum device (1632).

See also
● Guericke barometer
● Pascal atmospheric pressure experiment
● Torricelli vacuum

References
1. Sella, Andrea. (2016). “Torricelli’s barometer” (Ѻ), Chemistry World, Sep 5.