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The experiment uses a simple barometer to measure the pressure of air, filling it with mercury up until 75% of the tube. Any air bubbles in the tube must be removed by inverting several times. After that, a clean mercury is filled once again until the tube is completely full. The barometer is then placed inverted on the dish full of mercury.
The barometer arose from the need to solve a theoretical and practical problem: a suction pump could only raise water up to a height of 10 metres (34 ft) (as recounted in Galileo's Two New Sciences). In the early 1600s, Torricelli's teacher, Galileo, argued that suction pumps were able to draw water from a well because of the "force of vacuum."
An aneroid barometer is an instrument used for measuring air pressure via a method that does not involve liquid. Invented in 1844 by French scientist Lucien Vidi, [23] the aneroid barometer uses a small, flexible metal box called an aneroid cell (capsule), which is made from an alloy of beryllium and copper. The evacuated capsule (or usually ...
The parent of all mercury pressure gauges is the mercury barometer invented by Evangelista Torricelli in 1643. [15] An early engineering application of the mercury pressure gauge was to measure pressure in steam boilers during the age of steam. The first use on steam engines was by James Watt while developing the Watt steam engine between 1763 ...
A sphygmomanometer (/ ˌ s f ɪ ɡ m oʊ m ə ˈ n ɒ m ɪ t ə r / SFIG-moh-mə-NO-mi-tər), also known as a blood pressure monitor, or blood pressure gauge, is a device used to measure blood pressure, composed of an inflatable cuff to collapse and then release the artery under the cuff in a controlled manner, [1] and a mercury or aneroid manometer to measure the pressure.
Barometric light was first observed in 1675 by the French astronomer Jean Picard: [4] "Towards the year 1676, Monsieur Picard was transporting his barometer from the Observatory to Port Saint Michel during the night, [when] he noticed a light in a part of the tube where the mercury was moving; this phenomenon having surprised him, he immediately reported it to the sçavans, ... "[5] [6] The ...
1441 – King Sejongs son, Prince Munjong, invented the first standardized rain gauge. ... 1643 – Evangelista Torricelli invents the mercury barometer. [22]
Evangelista Torricelli invented the mercury barometer in 1643. The motivation for the invention was to improve on the suction pumps that were used to raise water out of the mines. Torricelli constructed a sealed tube filled with mercury, set vertically into a basin of the same substance.