When the tide at sea rises, the wa­ter in wells falls, and vice versa – some­thing known since around 100 BC and ex­plained only in 1940

Sky at Night Magazine - - MYSTERIOUS GRAVITY -

The Greek philoso­pher Po­sei­do­nios, who lived be­tween 135 and 51 BC, dis­cov­ered this ef­fect. He no­ticed that, when a spring at the tem­ple of Her­a­cleium in mod­ern­day Cadiz in Spain was low, the tide in the nearby At­lantic was high, and vice versa. The ex­pla­na­tion is that the grav­ity of the Moon, the prin­ci­pal cause of the tides, not only makes the ocean bulge up­wards but it does so to the rock as well. The wa­ter­logged rock in which a well sits is like a wet sponge. It sucks wa­ter out of the well when the sponge is stretched up­wards (high tide) and squeezes wa­ter back into the well when the sponge is re­leased (low tide).

The Moon doesn’t just cause tides, it causes the Earth it­self to bulge, some­thing that was seen (but not un­der­stood) in the un­usual be­hav­iour of a well

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