124 ABOUT THE WEATHER. 



The peculiar distribution of land and water upon the 

 globe, is one of the most important influences which essen- 

 tially modify the simple regularity of the distribution of 

 the weather. Land, when exposed to the rays of the sun, 

 becomes warm much more rapidly, and acquires a far 

 higher temperature than water, which, however, once 

 warmed, for the same reason cools the more slowly. The 

 immediate consequence of this is, that the hottest zone, the 

 region of the calms, is not divided into two equal parts by 

 the equator, but on account of the greater quantity of land 

 in the northern half, lies wholly on this side. This pro- 

 jection towards the north is most striking in the Indian 

 Ocean, where the north-east trade-wind blows in winter, but 

 in summer is wholly supplanted and replaced by the over- 

 powering south-east trade-wind. But on account of the 

 revolution of the earth, this must deviate to the west so 

 soon as it passes the equator, and thus the two trade- 

 winds are here formed, the north-east and south- 

 west winds, regularly alternating every six months, 

 which are called by sailors the monsoons. To us Euro- 

 peans, however, it is a fact of greater importance and 

 interest, that by the great Sahara so intensely heated 

 by the sun, the region of calms, and therefore that of the 

 Polar current or trade-wind, is pushed farther northward 

 into the south of Europe; so that the returning, warm 

 Equatorial current does not reach the ground nearly so far 

 south as is the case in Asia and America; or when it 

 descends early, as the Sirocco in Italy, or as the Fohn 

 in Switzerland, it is much hotter than elsewhere. It is 

 principally on this account, that Europe has a mild climate 

 so much farther toward the pole, than any other place in 

 the same latitude. While Rye is still cultivated in Ranen- 

 fiord in Norway, the same latitude of North America is 



