486 THE POPULAR SCIENCE MONTHLY. 



tudes, in Britain, for instance, we fall within the sway of the south- 

 rushing polar current deflected to the east by the earth's rotation, and 

 sometimes within that of the north-rushing current from the equator, 

 deflected to the west by the rotation which it shared with the earth at 

 the zone from which it started. In Britain this southwest wind comes 

 to us laden with vapor from the great mass of the Atlantic, and 

 makes Ireland and our western shores unusually damp and rainy. The 

 relative temperatures of sea and land in the temperate zones are con- 

 tinually changing with the seasons. In summer and autumn the At- 

 lantic is colder than the European Continent, and this has a tendency 

 to produce a west current at the surface. In winter and spring the 

 Atlantic is warmer than the continent, and this has a tendency to 

 produce an east wind. Sometimes one of these varying tendencies 

 gains the predominance and sometimes another, and the result is con- 

 stant and often rapid change and variety. The heat and moisture 

 which the wind brings with it depend entirely upon where it comes 

 from, and what it has passed in its way. A west wind blows to us 

 from the Atlantic, and usually brings rain ; an east wind brings up 

 the fog of the German Ocean ; and in winter and spring the prevalent 

 northeaster brings the cold and often the snow of Russia and Nor- 

 way. At the sea-side, unless it be overpowered by a general current, 

 there is a breeze from ofi" the sea during the day, and a breeze from 

 off the land during the night. The quantity of rain that falls in this 

 zone at different points is extremely variable, and depends upon the 

 position of a place with regard to mountain-masses and the seas from 

 which the vapors come. In England the rainfall is greatest on the 

 west side of the island, and smallest on the east. The difference with- 

 in a short distance is sometimes very striking. There are 140 inches 

 a year at Borrowdale, in the lake district, and not more than 20 inches 

 at Shields and Sunderland, which are directly opposite on the east 

 coast. But the habitual humidity of the atmosphere often varies but 

 little between places the rainfall of which is very different. The 

 number of days upon which more or less rain falls, varies in England 

 from 100 to 300, but in the Mediterranean region the number of days 

 is fewer, the quantity is smaller, and there is an almost regular period 

 of entirely dry weather in summer. Taking the north temperate zone 

 as a whole, there is, as a rule, least rain in places away from hills in 

 the interior of continents, and most in insular and mountainous situa- 

 tions. Gardenefs Chronicle. 



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