What Were the Key Arguments in the Early Classical Physics Water Pump Debate?

AI Thread Summary
The early classical physics debate on water pumps centered around Rene Descartes' rejection of the vacuum theory, proposing instead that the pump operates through the weight of water counterbalancing air pressure. This discussion highlights the tension between philosophical interpretations and practical physics, particularly regarding gauge versus absolute pressure. The mechanics of a draw pump, which uses atmospheric pressure to lift water, illustrate the limitations imposed by atmospheric pressure, with a theoretical maximum lift of about 32 feet. Practical applications reveal that the actual limit is slightly lower due to various factors. Understanding these principles is crucial for grasping the foundational concepts of fluid mechanics in classical physics.
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I read in the Britannica Encyclopedia yesterday that Rene Descartes rejected the idea that a water pump works because nature abhors a vacuum, and instead said that it works "by the weight of the water which counterbalances that of the air". I have an idea of the two contrary concepts opposed here, but its still a little fuzzy. Can someone help me understand what was at stake in those early discussions about classical physics and the water pump?
 
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I think that Descartes just didn't understand physics.
 
It is tough to translate philosophy to physics, but this sounds a bit like the "debate" between gauge and absolute pressure. A person who doesn't know the difference might not recognize that there is a limit to the value of negative gauge pressure (equal in absolute value to atmospheric pressure) and that absolute pressure can't go negative.
 
This argument possibly refers to a draw pump . That is a type of pump which has a vertical axis piston and cylinder arrangement with simple valves as used to draw water by hand from deep wells and bore holes . In use pump first draws a vacuum in the riser pipe and atmospheric pressure acting on water below ground then forces a column of water up into the pump body and ultimately out into a receiver (bucket) .

There is a limit to the depth which such a pump can raise water from . Simplistically limiting depth is equal to the height of a column of water which gives a static pressure at bottom of riser pipe equal to atmospheric pressure . That is about 32 ft . Practical limit is a bit less .
 
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