THE EARTH'S SHAPE 



tinental land areas rise. Finally, we find the nose of the 

 pear in the central Atlantic, between the Madeiras and 

 the Bermudas. Of course, the resemblance to a pear is 

 not a very marked one. Our observer a thousand miles 

 above the earth would not be able to perceive it, nor 

 would the astronomers in the moon, if any astronomers 

 existed there. But the earth is pear-shaped to a small 

 extent nevertheless, and in the case of such an enormous 

 mass a very slight deviation from rotundity will produce 

 very great effects. 



Most of us have played at such ball games as bowls 

 or billiards ; and I have assumed that everybody knows 

 something about golf. What happens in a game 

 at bowls to the bowl which is not evenly weighted 

 all through? It will not run straight. It has a bias. 

 What happens to a billiard ball which is not perfectly 

 round, or has lost its symmetry through age ? It wobbles. 

 And what happens to a badly made golf ball ? That 

 performs all sorts of exasperating antics. It ducks, it 

 soars, it curls, it takes a slice. It also wobbles. Now that 

 is exactly what the spinning, unevenly shaped globe which 

 we call the earth has been doing for millions of years. 

 It has been wobbling ; and as we showed in the last 

 chapter, it has always been trying to right itself. Thus 

 the two poles have not always been in the same position ; 

 the oceans have not always been where they are. The 

 waters have sometimes crawled up the land towards 

 the poles and sometimes receded. Regions that have 

 sometimes been frozen and cold have become warmer, and 

 have covered themselves now with oceans, and now with 



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