1 32 History of Nature. [BooK 1 1 . 



CHAPTER XCVI1. 



What is the Reason of the Ebb and Flow of the Sea : and 

 where it is that they keep no Order. 



OF the Nature of Waters much hath been said ; but that 

 the Tide of the Sea should flow and ebb, is a very wonderful 

 Thing indeed. The Manner thereof is various, but the Cause 

 is in the Sun and Moon. Between two Risings of the Moon 

 they flow twice and twice go back, and always in the Space 

 of four-and- twenty Hours. And first as she riseth aloft 

 together with the World, the Tides swell ; and presently 

 again, as she goeth from the Height of the Meridian Line 

 and inclineth Westward, they subside : again, as she moveth 

 from the West, under our Horizon, and approacheth to the 

 Point contrary to the Meridian, they flow, and then they are 

 received back into the Sea until she rise again : and never 

 keepeth the Tide the same Hour that it did the Day before : 

 for it giveth Attendance upon the Planet, which greedily 

 draweth with it the Seas, and evermore riseth to Day in some 

 other Place than it did yesterday. Nevertheless, the Tides 

 keep just the same Times between, and hold always six 

 Hours a-piece : I mean not of every Day and Night or Place 

 indifferently, but only the Equinoctial. For in regard of 

 Hours, the Tides of the Sea are unequal : forasmuch as by 

 Day and Night the Tides are more or less one Time than 

 another : in the Equinoctial only they are equal in all Places. 

 A powerful Argument this is, and full of Light, to convince 

 the Dulness of those who are of opinion, that the Planets 

 being under the Earth lose their Power : and that their 

 Virtue beginneth when they are above only. For they shew 

 their Effects as well under as above the Earth, as well as the 

 Earth which worketh in all Parts. And plain it is, that the 

 Moon performeth her Operations as well under the Earth as 

 when we see her visibly above : neither is her Course any 

 other beneath than above our Horizon. But yet the Altera- 

 tion of the Moon is manifold, and first every seven Days: 

 for while she is new, the Tides be but small, until the first 



