The Tides. 217 



will also examine the remarks of others on this subject and see 

 how they agree. 



The Neve Am, Cjc. says : " The close relation which the times 

 of high water bear to the times of the moon's passage shows that 

 the moon's inflaence in raising the tides must be greater than the 

 sun's. In fact, while the whole attraction of the sun upon the 

 earth far exceeds that of the moon, yet, owing to the greater prox- 

 imity of the latter, the difference between its attraction at the 

 center of the earth and at the nearest and most remote points of 

 its surface, which produces the tides, is abaut two and one-half 

 times as great as the sun's attraction at the same points." 



The argament might answer if the moon was very near the 

 earth so as to gather the water by tangental motion into a wave 

 beneath it until resisted by gravitation, provided also, that suffi- 

 cient time was allowed, as we are not dealing with a uniform en- 

 velop of water, but with oceans separated by continents, and 

 although the velocity of the tides is great, the translation of the 

 water is very slow, not such as would be required in heaping up 

 the water as the moon overleaps the continents from ocean to 

 ocean, whereas the wave comes up as though impelled by a sud- 

 den blow or stroke. An article on tides by repulsion in Yol. 4 

 of the South. Litt. Mess, says : " When La Place ^ had ascertained 

 the fact, that as the mooon passed over the Atlantic it was low 

 water under her and the swell was on either side of her, north 

 and south, and the further from the moon the greater the swell, is 

 it not a little strange that he should have come to the conclusion 

 that the moon was drawing up the water towards herself," further 

 from the same ; " as whenever the moon is vertical to any place, 

 it is invariably low water." These remarks, when properly ap- 

 plied, are correct so far as the position of the wave is concerned. 

 Bowditcb in Mech. Celeste says: "Bj^ a remarkable singularity, 

 the low water takes place when the two bodies are in the meridian, 

 and the high water when they are in the horizon ; so that the tide 

 subsides at the equator, under the body that attracts it." li ap- 

 pears that the origin of the lide is lost sight of, and the time 



•1 La Place. Born, 1748; died, 1827. 



