noun: an abnormal backward flow of body fluids
noun: the outward flow of the tide
Schauberger
1. It is a known fact that in high pressure boilers a reflux from high to medium pressure takes place under certain circumstances without the hermetic seal being broken[10]. Up to now this occurrence could not be explained and because of it the manufacture of miniature pressurised boilers was abandoned, which meant, of course, that veritable mechanical monsters had to be put up with, which consumed a great deal of space and material. [The Energy Evolution - Harnessing Free Energy from Nature, The Liquefaction of Coal by Means of Cold Flows]
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