CAUSE OF THE SEASONS 



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north, or until its rays fall vertically upon the tropic of 

 Cancer. This occurs on the 21st of June, which is called 

 the summer solstice. -At this time our days are the longest 

 and our nights the shortest. But the days are not the 

 hottest, as the heat gradually accumulates for some time, 

 more being received each day than is given off. 



As the earth proceeds in its orbit from this point, the 

 inclination of the north pole toward the sun becomes less 



HUT IN THE TROPICS. 

 Made of thin walls but a heavy thatched roof to keep out the rain. 



and less, until on the 23d of September the sun is directly 

 over the equator. The north pole now begins to point 

 away from the sun. On December 21 the direct rays of 

 the sun fall upon the tropic of Capricorn, and the sun has 

 reached its farthest point south, our days being then the 

 shortest and the days in the southern hemisphere the 

 longest. From this point until March 21, when the sun is 



