Noun
barometer that shows pressure by the height of a column of mercury
Source: WordNetBuilding upon Galileo's notes, he built the first mercury barometer and wrote a convincing argument that the space at the top was a vacuum. Source: Internet
Mercury barometers A mercury barometer has a glass tube closed at one end with an open mercury-filled reservoir at the base. Source: Internet
The mercury barometer stood lower the higher one went. Source: Internet