CHAPTER VI. 



TRADE-WINDS STORMS THEIR EFFECTS MONSOONS THEIR VALUE 



LAND AND SEA BREEZES EXPERIMENTS HURRICANES 



THOSE OF 1831 ROTATORY STORMS THEIR TERRIBLE EFFECTS 



CHINA SEAS HURRICANE IN 1837 WHIRLWINDS WEIGHT 



OF ATMOSPHERE VALUE OF ATMOSPHERIC CIRCULATION 

 HEIGHT OF ATMOSPHERE. 



'ORE proceeding to speak of the power 

 and the dreadful effects of wind, it is 

 necessary* to say a word or two about the 

 trade-winds. 



It is supposed that the " trades " derived their 

 name from the fact of their being favourable to 

 navigation, and, therefore, to trade. They consist 

 of two belts of wind, one on each side of the 

 equator, which blow always in the same direction. 



In the last chapter it was explained that the 

 heated atmosphere at the equator rises, and that 

 the cooler atmosphere from the poles rushes in to 

 supply its place. That which inshes from the 

 south pole is, of course, a south \v_'nd, that from 

 the north pole a north wind ; but, owing to the 

 Earth's motion on its axis from west to east, the 



