188 FROM NEBULA TO NEBULA 



hand, in the course of their separation and removal to 

 the original distance, would naturally repeat these 

 phases, but in just the reverse order (See Fig. 7). 



Speaking specifically of the earth, then (though the 

 principle applies universally), her tides are caused by a 

 conflict between two ruling gravitational forces, namely, 

 (1) the integral attraction of the earth upon her own 

 mass, and (2) the extraneous attraction of the sun; the 

 first seeking ever to concentrate her heavier substances 

 at her center and to deploy the lighter on the outside, 

 the latter ever striving to compel her to recognize the 

 sun's rival power and advance her heavier parts toward 

 him. Were the earth solid clear through, as the moon 

 appears to be, she would turn the same face to the sun 

 continuously, but having great mobile oceans, she com- 

 promises by shifting them from in front of the sun, thus 

 giving her center of gravity, as it were, a chance to make 

 obeisance to him. 



COMPUTATION or THE TIDAL FORCES 



It will be remembered that, according to Newton's 

 idea, the waters making up the tidal mounds are con- 

 strued as being drawn thither obliquely from the rounded 

 sides of the earth ; whence he argues that the tidal forces 

 of the sun and moon do not vary in accordance with the 

 rule of inverse squares, as the law of gravitation has it, 

 but of the inverse cubes. As a result of this hypothesis, 

 he estimated the ratio of the sun's effect to thai of the 

 moon as (about) one to four. If we are right, however, 

 in our new hypothesis that the tides are acts of equili- 

 brism, the solar and lunar tidal forces vary, not accord- 

 ing to the exception, but strictly according to the letter 

 of the law itself. Thus calculated, they vary as 180 to 1, 

 this time with the sun having the advantage a total 

 change of 720 points! 



Knowing as we do the relative masses of the earth 

 and sun (1 to 332,000) and the earth's radius as compared 

 with the solar distance (1 to 23,000), we can easily find 

 by applying the law of gravitation that the earth's at- 



