204 EBB AND FLOW. 



in a place where the influence of the heavenly bodies does 

 not penetrate ; but, which is our present subject, the more 

 superficial crusts or formations of the earth appear to agree 

 with the conversions of the sun, air, and waters, as far as 

 solid and fixed bodies can agree with liquid and fluid, 

 that is, not that they move towards the poles, but are 

 pointed and turned towards the poles. For since every 

 revolving sphere, which has fixed poles, participates of the 

 nature of moveable and fixed ; after, by its consistency or 

 self-determining nature, the rotatory force is bound up, 

 still the force and tendency to direct itself remains, is aug 

 mented and gathered into one ; so that direction and ver- 

 ticity to the poles in hard bodies is the same with the 

 revolution on their poles in fluids. 



The third inquiry remains. Whence and how arises that 

 reciprocal action of the tides, once in six hours, which 

 coincides with a quarter of the diurnal motion, with that 

 difference to which we have adverted. To understand this, 

 let us suppose that the whole globe was covered with water, 

 as in the general deluge ; we conceive the waters as form 

 ing a complete and unbroken globe, would always roll in a 

 progression from east to west each day to a certain extent : 

 not certainly a great space, on account of the remission 

 and debilitation of that motion as it approaches the earth ; 

 seeing the waters were no where obstructed or confined. 

 Let us suppose again, that the whole land was an island, 

 and that it extended longitudinally between south and north, 

 which conformation and position most restrain and ob 

 struct the motion from east to west; we think that the 

 waters would keep on in their direct and natural course for 

 a certain time, but, reverberated by the shores of that island, 

 would roll back in equal intervals, that there would be, 

 therefore, only one influx of the sea a day, and in like 

 manner only one reflux, and that to each of these about 

 twelve hours would be apportioned. And let us now sup 

 pose what is true and matter of fact, that the land is divided 

 into two islands, those, namely, of the new and old world ; 

 for Australia, by its position, does not much alter the effect, 

 as neither does Greenland nor Nova Zembla, and that 

 these two islands extend through nearly three zones of the 

 world, between which two oceans, the Atlantic and Southern, 

 flow, and these nowhere find a thoroughfare, except towards 

 the Poles ; we think it necessarily follows, that these two 

 ramparts impart and communicate the character of double 

 reaction to the entire mass of waters. Whence arises that 



