bunghole
noun: a hole in a barrel or cask; used to fill or empty it
Schauberger
trout, which, floating upwards, are able to surmount freely overfalling waterfalls several metres high, if particularly hollowed out flow-guiding stones cause the falling water to flow in 'cycloid-spiral-space-curves', the form of motion that arises and can be observed above every bunghole through which water is able to free-fall. This how the water-inwinding suctional forces evolve and the reactive forces acting in the opposite direction come into being in the axis of the suction-vortex. It is the latter forces that are at issue here. Today's science, which measures and weighs everything exactly, overlooked them, because the 'producer of measure and weight' can neither be measured with a yardstick, nor weighed with decimal scales. [The Energy Evolution - Harnessing Free Energy from Nature, The Life-Current in Air and Water]
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