THE EARTH A MAGNET, 17 



except the north-eastern parts of Eussia; Turkey, 

 Arabia, and the whole of Africa ; the greater part of 

 the Indian Ocean, and the western parts of Australia ; 

 nearly the whole of the Atlantic Ocean ; Greenland, 

 the eastern parts of Canada, and a small slice from the 

 north-eastern part of Brazil. All these form one region 

 of westerly decimation ; but, singularly enough, there 

 lies in the very heart of the remaining and larger region 

 of easterly magnets an oval space of a contrary character. 

 This space includes the Japanese Islands, Manchouria, 

 and the eastern parts of China. It is very noteworthy 

 also, that in the westerly region the declination is much 

 greater than in the easterly. Over the whole of Asia, 

 for instance, the needle points almost due north. On 

 the contrary, in the north of Greenland and of Baffin's 

 Bay, the magnetic needle points due west ; while still 

 further to the north (a little westerly), we find the 

 needle pointing with its north end directly towards the 

 south. 



In the presence of these peculiarities, it would be 

 pleasant to speculate. We might imagine the existence 

 of powerfully magnetic veins in the earth's solid mass, 

 coercing the magnetic needle from a full obedience to 

 the true polar summons. Or the comparative effects 

 of oceans and of continents might be called into play. 

 But unfortunately for all this, we have to reconcile 

 views founded on fixed relations presented by the earth 

 with the process of change indicated above. Let us 

 consider the declination in England alone. 



In the fifteenth century there was an easterly decli- 



c 



