258 On the Rise of Water in the Chesswater Mine. [Oct. 



dation for his notions as to the nearer parts having an excess of gra- 

 vity to the centre of the orbit, the tide thereby occasioned would be 

 a solar tide, and wouid correspond to the forces of the attraction of 

 the <-un, and not of the moon. In truth, however, there is no foun- 

 dation for the opinion of your Correspondent, as to the excess of 

 centrifugal and centripetal forces in the farther and nearer parts ; 

 and therefore I need not pursue the argument against them. What 

 I wish chiefly to suhmit to your consideration, and through your 

 work to those who will admit of no improvement on the discoveries 

 of Newton, is the circumstance, that the Newtonian theory of the 

 antilunar tide, as well as that opposed to it by Mr. Ferguson, re- 

 quires certain movements of the earth, which withdraw the pheno- 

 menon from being the simple effect of gravitation. 



This, though not conclusive, appears to my mind a strong cb-- 

 jection to the Newtonian theory. The lunar tide is admitted on all 

 hands to be a simple effect of the moon's attraction; but when we 

 inquire as to the cause of the opposite tide, another principle is in- 

 troduced in aid of what on the nearer hemisphere is of itself 

 sufficient. Every analogy pleads against this : besides, if the 

 moon's attraction is strong enough to produce such an effect on one 

 side of the earth, what arrests its progress, what sets the bound to 

 its operation, on the opposite side? It must operate with a force 

 diminished merely by the increased distance; and therefore any 

 other additional principle would, as I have elsewhere stated, pro- 

 duce a redundant effect. 



I beg leave to put a question, to which I hope for a reply. Sup- 

 pose the miracle of Gideon were to be repeated on a more extensive 

 scale ; that the voice which bade the planets roll were to fix them 

 stationary in any points of their orbit ; in such circumstances, 

 would or would not the antilunar tide cease to flow? The lunar 

 tide, it will not be disputed, would continue to oblongate the earth. 

 Would there be no corresponding swell on the opposite hemisphere? 

 Let the Newtonian explain how this would happen on his prin- 

 ciples ; I need not recall to your recollection the simplicity with 

 which it is explained on mine. 



I am, dear Sir, yours faithfully, 



John Campbell. 



Article V. 



On the Rise of Water in the Chess-water Mine. 

 By Mr. John B. Longmire. 



[To Dr. Thomson ] 

 SIR, 



I rkad in a late Number of your valuable journal some questions 

 by Mr. Movie, of Helston, in Cornwall, respecting the entrance of 

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