WINDS. 



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coasts is said to be owing to the moisture brought by the winds. We 

 think this is produced by the descent of the cold currents of air flow- 

 ing from the upper strata to the warmer surface areas, condensing the 

 vapor which has arisen from evaporation over a small extent of ocean 

 near to the coast. The action of the Southwest Monsoon, particularly, 

 is often referred to, as transporting the vapors which cause the copious 

 rains on the coast of India; — but according to the theory, the currents 

 of air seeking this coast are cold, and comparatively dry ; but descend- 

 ing into the vapor plain, to the w r armer areas, they produce condensa- 

 tion, and great precipitation follows. The effect may be increased by 

 the height of the Western -Ghauts, which rise immediately above the 

 line of coast, and act to retard and condense a portion of the vapor as 

 it is left behind. 



It has been thought that winds from certain directions always bring 

 rain ; but in places not far distant from each other, they are altogether 

 from opposite quarters wdiich produce this phenomenon. It often 

 happens that the wind from the same direction at one season produces 

 rain, while at another it is attended with fine weather. This is the 

 case with the northeast winds of Europe, and also with the northeast 

 winds on our own coasts. Everyone is familiar with the name of dry 

 northeaster. In Europe, at one season, the moisture is condensed on 

 the Ural Mountains, lying perpendicular to the flow of vapor, by 

 which the rivers flowing to the north and south from them are sup- 

 plied ; — consequently, none can flow onward to the west. At other 

 times, the vapor passes onward, and is condensed farther to the west, 

 in the centre of Europe. Many instances could be cited to show that 

 this is the case in other places. In Germany, more rain falls than on 

 the coast of France in the same latitude. 



It has been often observed that the rains of one wind are different 

 in character from another. This evidently depends upon the rapidity 

 of the condensation : if the air which flows in be but a few degrees 

 cooler, the condensation will be slower, and the precipitation more 

 nearly allied to mist. As the difference in temperature is greater and 

 more sudden, there will be violent rains, and often hail, — and this 

 latter extends in narrow widths over areas ; while beyond them, the 

 temperature not falling so low, rain only will take place. 



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