The first one.......

Friends, have you ever heard about the word Barometer - Pronunciation: [b u rom´ u t u r]. You heard it somewhere, but can’t able to recall it right. Don’t worry “The First One” is there for you - a Barometer is an instrument for measuring atmospheric pressure. Two common types are the aneroid barometer and the mercurial barometer (invented first). Evangelista Torricelli invented the first barometer, known as the "Torricelli's tube".

Evangelista Torricelli was born October 15, 1608, in Faenza, Italy and died October 22, 1647 in Florence, Italy. He was a physicist and mathematician. In 1641, Evangelista Torricelli moved to Florence to assist the astronomer Galileo.

It was Galileo that suggested Evangelista Torricelli use mercury in his vacuum experiments. Torricelli filled a four-foot long glass tube with mercury and inverted the tube into a dish. Some of the mercury did not escape from the tube and Torricelli observed the vacuum that was created.

Evangelista Torricelli became the first scientist to create a sustained vacuum and to discover the principle of a barometer. Torricelli realized that the variation of the height of the mercury from day to day was caused by changes in the atmospheric pressure. Torricelli built the first mercury barometer around 1644.

Now I believe that, you are cleared about the term barometer. See you in next post, bye…