mercury barometer

American  

noun

1. a barometer in which the weight of a column of mercury in a glass tube with a sealed top is balanced against that of the atmosphere pressing on an exposed cistern of mercury at the base of the mercury column, the height of the column varying with atmospheric pressure.

---

Usage

What does mercury barometer mean? A mercury barometer is a barometer with a column of mercury whose height varies according to the atmospheric (barometric) pressure. A barometer is an instrument for measuring atmospheric pressure, which is used in forecasting the weather. Mercury barometers are no longer in wide use, having been replaced by other methods of measuring pressure, such as aneroid barometers, which use a small capsule with flexible walls that expand or contract in response to changes in atmospheric pressure.

Example Sentences

A mercury barometer is shown in Figure 11.21.

From Textbooks • Aug. 12, 2015

Figure 11.21 A mercury barometer measures atmospheric pressure.

From Textbooks • Aug. 12, 2015

A mercury barometer is a device that measures atmospheric pressure.

From Textbooks • Aug. 12, 2015

For this purpose, however, a barometer is used that is more easily carried than a mercury barometer.

From The Story of Great Inventions by Burns, Elmer Ellsworth

If we take a mercury barometer up a hill we will observe that the mercury falls.

From The Mastery of the Air by Claxton, William J.