The History of Pressure Measurement 1594 Galileo Galilei, born
in Pisa (Italy), obtains the patent for a machine to pump water
from a river for the irrigation of land. The heart of the pump
was a syringe. Galileo Galilei found that 10 meters was the
limit to which the water would rise in the suction pump, but had
no explanation for this phenomenon. Scientists were then devoted
to find the cause for this. 1644 Evangelista Torricelli (rorr).
Italian physicist, filled a tube 1 meter long, hermetically
closed at one end, with mercury and set it vertically with the
open end in a basin of mercury. The column of mercury invariably
fell to about 760 mm, leaving an empty space above its level.
Torricelli attributed the cause of the phenomenon to a force on
the surface of the earth, without knowing, where it came from.
He also concluded that the space on top of the tube is empty,
that nothing is in there and called it a "vacuum". 1648 Blaise
Pascal, French philosophei physicist and mathematician, heard
about the experi