EBB AND FLOW. 195 



its place. If there were a fresh quantity of water added, 

 it must be by flowing and eruption from the earth. If 

 there were dilatation only, this must take place either by 

 solution into greater rarity, or by a tendency to approach 

 another body, which as it were evokes the waters, attracts 

 them, and lifts them to greater elevation. And, doubtless, 

 that state of the waters, whether considered as ebullition, 

 or rarefaction, or harmony with some one or other of the 

 heavenly bodies, cannot seem incredible, that is to a moderate 

 extent, and on the supposition of the lapse of considerable 

 time, in which such swellings and accretions may gather 

 and accumulate. Therefore the difference observable be 

 tween the ordinary, and the half monthly tide, or the most 

 copious of all, the half yearly one, in which the addition to 

 the mass of waters, is not equal to the difference between 

 ordinary ebb and flow, and has besides a large interval of 

 time insensibly to form, may, on the hypothesis of eleva 

 tion and depression, be consistently explained. But that 

 so great a mass of water should burst forth as to ex 

 plain that difference which is found between the ebb and 

 flow, and that this should take place with such extreme 

 rapidity, namely, twice a day, as if the earth, according to 

 the fantastic notion of Apollonius, performed respiration, 

 and breathed waters every six hours, and then again in 

 haled them, is very hard to believe. And let no man be 

 misled by the unimportant fact that in some places wells 

 are said to have a simultaneous motion with the ebb and 

 flow of the sea, whence one might conjecture, that waters 

 inclosed in the entrails of the earth boil up in like manner, 

 in which case that swelling of the waters cannot be attri 

 buted to a progressive motion. For the answer is an easy 

 one, that the flow of the sea by its encroachment may per 

 forate and gorge many hollow and loose places of the earth, 

 turn the course of subterraneous waters, or cause a rever 

 beration of the inclosed air, which by a continued series of 

 impulsions may raise the water in this sort of wells. Ac 

 cordingly this does not take place in all wells, nor even in 

 many, which ought to be the case if the entire mass of 

 waters had a property of periodically boiling up, and a 

 harmony with the tide. But on the contrary, this rarely 

 happens, so as to be regarded almost as a miracle, because 

 in fact such apertures and spiracles as reach from wells to 

 the sea, without circuity or impediment, are very rarely 

 found ; nor is it unimportant to mention, what some relate, 

 that in deep pits situated not far from the sea, the air be- 



