STUDIES IN NATURE 



of the land lie great stretches of ocean, and to 

 the south-west the ocean is warmed by the 

 southern sun, and also by a slow but mighty 

 current in the water, which comes from the 

 tropical seas near the Gulf of Mexico, and is 

 called the Gulf-stream. We already know that 

 warm water tends to evaporate and mix with the 

 air as invisible vapour. The winds which blow 

 over the warm ocean will therefore take up a 

 large amount of water-vapour, and when they 

 reach our colder regions the vapour may con- 

 dense as rain, just as drops of water condense 

 on the inside of our bed-room window when it 

 is chilled by the outside air on a cold night. It 

 is but natural then that south-west winds should 

 often bring rain. To the east and north-east of 

 Britain lie large tracts of land, and very little sea 

 until we reach the frozen Arctic Ocean. Winds 

 passing over the vast plains of Russia and cen- 

 tral Europe can absorb no moisture, and when 

 they reach our shores are usually very dry. 



Besides noticing the connection between 

 rainy days and the direction of the wind, let 

 us also think which winds bring hot and which 

 bring cold weather. Now we shall find that 

 there is a difference in this according to the 

 season of the year. In winter the north-east 

 winds usually bring cold, or even frost, while 

 south-west winds accompany mild and open 

 weather. In summer a north-east wind, if it is 

 not too strong, means hot, scorching sun, with 



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