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During the 17th century there was an obvious need to lift of liquids at a certain height so as to make various apparatuses to work. Pumps were normally used to accomplish this task, but these were only slightly improved versions of the pump of Heron of Alexandria dated back to the Hellenistic period almost 16 centuries earlier. These were incapable to lift the water at a height higher than 10 meters above the original level of the water.
Siphons are of little help if one wants to lift water over a hill using it, in order to bring water to a village behind a hill, for example. This is because the siphon does not function if the height of the column is such that the liquid pressure is higher than the atmospheric one. Mine-pits, were often flooded from underground water, but if people were digging at great depths the commonly used pumps were not sufficient to pump it out. For all these, the explanation given, at the time, was that it was due to the imperfections of the materials used e.g. the pipes were made out of wood and any seals were also imperfect letting air in. The solution came from a collaborator of Galileo, namely Evangelista Torricelli (1608-1647).
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