THE TIDES AND TIDAL ROTATION 83 



of this book, a quantity less than 1/lOth of the sun's 

 daily evaporating effect!* 



Here I fancy the reader saying, "Your argument 

 seems plausible, but its very simplicity condemns it. 

 It is inconceivable that more than two centuries of 

 brilliant scientists should have overlooked things so 

 obvious. There must be a screw loose somewhere/' This 

 is always the hardest argument for the pioneer to 

 answer. I daresay it was used to Copernicus when, 

 after fourteen centuries of Ptolemaic tradition seven 

 times longer than that with which I have to contend 

 he dared to suggest that maybe after all it was only 

 our earth and not the universe that was moving. 



The first impulse of the general reader, had he orig- 

 inally analyzed all this is the class-room, would doubt- 

 less have been to scoft' at the notion that the tidal action 

 of this one-fiftieth of an inch as compared with the full 

 ocean depth of 13,000 feet can by any possibility con- 

 stitute the sufficient explanation of the enormous 

 diurnal tides witnessed on our coasts, or that even the 

 accession out of nothingness of a fresh sheet of water 

 of that thickness could swell the ocean to the formidable 

 tidal states we see. However, had the same reader been 

 faced with the harsh alternative of either accepting this 

 myth or repudiating the principle of universal gravita- 

 tion altogether, he would probably have followed the 

 example of the whole scientific world before him, and 

 humbly submitted to the inevitable. 



In a former chapter we saw how Newton in striving 

 to prove his theory of centripetal gravitation, was con- 



*I leave to others the calculation of what the tidal depths 

 should be under my theory, partly because mathematical discussion is 

 beyond the scope of the present book, and partly because the prin- 

 ciple of depression of the water as opposed to that of lifting*, raises a 

 question of physical fact to which only careful experimenting can 

 furnish conclusive answer. It may be said generally, however, that 

 the effects of both sun and moon would be hundreds of times greater 

 than under the present computations. 



