218 



WEATHER AND CLIMATE 



The Effect of the Earth's Rotation on Winds. Experiment 



78. Revolve a globe from left to right and while it is revolving draw 

 a piece of chalk from the pole toward the equator. Does the line 

 as marked on the globe follow a meridian? What is its genera! 

 direction in lower latitudes? While the globe is revolving, allow 

 a drop of water to run from one pole to the other. Note the path 

 it takes. 



The rotation of the earth affects the direction of move- 

 ment of all bodies free to move over its surface. Thus if 



EFFECT OF PREVAILING WIND ON GROWING TREES 



a current of air starts from the north pole to flow south, it 

 will, as it goes along, tend to move toward the right, and so 

 when it reaches middle latitude it is no longer moving 

 south but southwest. Why this is so can be fairly well 

 understood if the conditions of this moving body of air 

 are considered. 



