THE EARTH'S SHAPE 



ocean. But now let the reader move round the earth to 

 a point exactly opposite that at which he took his first 

 observations and look down again. He will now see the 

 Australian continent and the land which covers the 

 South Pole, but except for the pointed tail of South 

 America, and perhaps a glimpse of the blunter point of 

 South Africa, he will be looking down on a globe which 

 seems to be largely covered with water. 



Why should this be ? It must be due to the shape of 

 the earth. The fact is, the earth would make a very bad 

 golf ball. It is by no means of that perfection of sym- 

 metry which they say enables a golf ball to fly well and 

 to run true on the putting greens. The earth is, in fact, 

 not perfect as a sphere, either within or without. Its 

 centre is not in the same place as the centre of its 

 weight, and it is not round in shape. Everybody has 

 heard that the earth is slightly flattened at the poles; 

 but its irregularity goes much further than that. If we 

 could strip it of its oceans, which fill up a good many 

 of its imperfections, we should find its shape not that of 

 a neat, round golf ball at all. The earth^s actual shape 

 without its oceans, its "geoid," as it is called, is that 

 of a pear. The stalk of the pear is in the southern part 

 of Australia, and contains Australasia and the Antarctic 

 continent. This is surrounded on all sides but one 

 (towards South America) by a sort of belt of depression 

 in which the waters lie. That is the waist of the pear. 

 This again is surrounded on all sides but one (towards 

 the east of Japan) by a belt of elevation. That is the 

 protuberant part of the pear, and here the great con- 

 Si 



