68 THE CLIMATE OF AUSTRALASIA 



and very scanty rains, which fall at irregular 

 intervals. The recognition of these meteoro- 

 logical provinces is of primary importance, 

 because it helps us to understand why the same 

 meteorological variation affects some localities 

 simultaneously, and others at different times. 

 For the solar variation affects different regions 

 by a different chain of circumstances. Thus 

 Mauritius, being in a different meteorological 

 province from Bombay, may feel the effects of 

 the same variation in the great controlling 

 agent at a different date. 



Moreover, there are interesting cases in 

 which areas on the earth's surface, which are 

 antipodal in position, have their meteorological 

 variations reversed. Some parts of India lie 

 under high pressure, while their antipodes in 

 North America are under low pressure.* This 

 opposition is to some extent a necessary con- 

 sequence of the antipodal positions of land and 

 water on the globe. Nearly every point on 

 the land of the globe has water at its antipodes. 

 In fact, only x / 27 of the land surface of the 

 world has land at its antipodes. As there is 

 then a see-saw oscillation between the conditions 

 of continents and oceans, it is only natural that 

 antipodal localities, though they may show the 

 same cycle, have their meteorological circum- 

 stances reversed 



* Sir Norman and W. J. S. Lockyer, " On the Similarity of the 

 Short-period Pressure Variation over large Areas," Proc. Royal Soc. , 

 Vol. LXXL, 1903, pp. 134-5. 



