Edwin. — Meteorology of New Zealand. 



567 



time the movement is back again northwards. These changes 

 follow the date of the change of declination. Temperature 

 decreases in all northern systems during the southward move- 

 ment, but increases in all the southern systems, the reverse 

 taking place with the northward movement. 



The demands of life, land, and water are enormous, con- 

 stant, and imperative, and therefore there must be continual 

 changes in atmospheric conditions near the earth's surface, 

 necessitating constant renewal. 



The Theory op the Mechanical Principle of Atmospheric Circu- 

 lation. 



■ws 



VP. Variable polar winds. 

 PA. Anticyclones of Arctic 

 region. CP. Cyclones of 

 Arctic region. W. West- 

 wind belt of Northern 

 Hemisphere. ANB. Anti- 

 cyclones of northern belt. 

 CN. Cyclones of Northern 

 Hemisphere. E. Equator- 

 ial belt of low pressure. 

 ASB. Anticyclones of south- 

 ern belt. CS. Cyclones of 

 Southern Hemisphere. 

 W. West -wind belt of 

 Southern Hemisphere. 

 AA. Anticyclones of Ant- 

 arctic region. CA. Cyclones 

 of Antarctic region. VA. 

 Variable winds of South 

 Pole. 



Feathered arrows show routes, 

 all of which are eastward. 

 Unfeatbered arrows show 

 wind-movements. 



