LESSONS IN PHYSICS. 49 



instead of being north and south winds, are northeast winds 

 north of the equator, and southeast winds south of the equator. 

 Those currents going from the equator, having the more rapid 

 motion of places near the equator, are constantly getting in ad- 

 vance of places having the same longitude as those from which 

 they started, so that north of the equator they are southwest 

 winds instead of south winds, and south of the equator they are 

 northwest winds instead of north winds. Numerous observations 

 show that the winds between 32 N. and 25 S. have the direc- 

 tions given above. 



As the land is a better absorber of heat than the water, in the 

 torrid zones and during summer in the temperate zones, it be- 

 comes hotter than the water during the day, and the air over the 

 land becomes hotter and lighter than that over the water, which 

 gives rise to a wind from the sea toward the land, called the sea 

 breeze. The land is also a better radiator than the water, so 

 that during the night the land becomes cooler than the water, 

 and the air over the land becomes heavier than that over the 

 water, which gives rise to a wind from the land toward the sea, 

 called the land breeze. The land and the sea breeze illustrate 

 how variations in the surface of the earth serve to promote mo- 

 tions in the air. 



L. S. 4 



