PART IV. THE WEATHER CYCLE. 



IF our weather be determined by the remote 

 upwelling of water from the deep seas, it may 

 be thought to be absolutely at the mercy of 

 irregular proceedings that we can neither 

 control nor foretell. It may seem necessary 

 once for all to abandon the quest for that Holy 

 Grail of meteorology the key to the succession 

 of good and bad seasons. The highest aim of 

 meteorology is to determine whether there is 

 any regular succession of wet and dry periods, 

 and, if there be, the discovery of the law that 

 regulates them. Belief in ordered, periodic 

 weather cycles has existed at least since the 

 time when Joseph made the family fortune by 

 predicting the seven lean and seven fat years 

 in Egypt, and turning it to account by his 

 preferential trade. The search for the secret 

 of Joseph's success has engaged the attention 

 of ambitious men from that day to this. The 

 search has been stimulated by many encourage- 

 ments on the way. Weather records often 

 show remarkable periodicity, which has led 

 man after man to think that the key was almost 

 within his grasp. Meteorological literature 

 abounds with remarkable cases of the occur- 

 rence of the same weather conditions at regular 



