44 CONVERGENCE OF EVIDENCE OF A 



drawing northwards, raise the Pacific level above that 

 of the Atlantic. But, if such were the case, then that 

 same force should, by drawing the water away from 

 the Atlantic shore of the isthmus, depress the level of 

 the Caribbean Sea below the general level of the 

 Atlantic. It would be completely at variance with 

 that which we suggested, in vol. i., as the cause of 

 the greater accumulation of land in the northern than 

 in the southern hemisphere. And it would leave the 

 observed oscillations of the barometer unexplained. 

 For, as stated in our preceding chapter, in the 

 southern hemisphere the barometer is lower when 

 that hemisphere is in advance in the orbital motion 

 of the earth than when the northern hemisphere is 

 in advance: and also in the northern hemisphere 

 the barometer is lower when that hemisphere is 

 in advance, than when the southern hemisphere 

 is in advance. And, since the average height of 

 the barometer is lower in the southern hemisphere 

 than in the northern hemisphere, therefore the evi- 

 dence deduced from the barometer tends to show 

 that in the motion of the solar system through 

 space the southern hemisphere of the earth is in 

 advance. 



The evidence deduced from these various sources 

 harmoniously converges towards the demonstration 

 of a motion of the earth in the direction of the south 

 pole. The denial of that motion throws all into dis- 

 cord and confusion. And even though the evidence 



