Chap. IV.] GRAVITATION AND INERTION. 63 



brought into play in the ocean and atmosphere by 

 the motions of the earth. 



As regards the earth's onward motion through 

 sj)ace, we have shown that, in consequence of the 

 action of friction along the shores and bottom of the 

 ocean, vis-inertia3 causes a current along the surface 

 of the deep and central parts of the ocean, where it 

 is comparatively free from the opposing action of the 

 force termed friction, in the ordinary acceptation of 

 the term ; whilst counter -currents return inshore to 

 the source of action. In this case the vis-inertia3, 

 which drives a current through the surface of the 

 deep and central parts of the ocean in the opposite 

 direction to that of the motion of the earth, is astral 

 gravitation drawing those particles which, in conse- 

 quence of their position in the ocean, are most free to 

 follow the influence of its attraction, towards the 

 position which its power of gravitation tends to give 

 them. And the friction which opposes the force of 

 astral gravitation along the shores and bottom of the 

 ocean is the earth's gravitation, which, in consequence 

 of the particles in those parts of the ocean being 

 more under its dominion than those at the surface of 

 the deep and central parts of the ocean, draws them 

 into the position which it tends to give, and conse- 

 quently carries them to those positions in relation 

 to the surface of the earth which the particles most 

 under the dommion of astral gravitation tend to 

 vacate. 



