Barometers

Suction pumps in early mines mysteriously failed to lift water higher than 33 feet. Investigating this physical limit, Galileo’s student Evangelista Torricelli invented the barometer. His elegant mercury experiment proved that the atmosphere exerts measurable pressure that dictates this limit.
 Evangelista Torricelli Italy 1643 Barometers

Suction pumps in early mines mysteriously failed to lift water higher than 33 feet. Investigating this physical limit, Galileo’s student Evangelista Torricelli invented the barometer. His elegant mercury experiment proved that the atmosphere exerts measurable pressure that dictates this limit.