RAINFALL AND EVAPORATION 



amount of water for their full develop- 

 ment. Hence the term "dry-land crops" 

 simply means certain plants that are able 

 to thrive and give good returns in regions 

 where the rainfall is low or irregular. 

 Again, it is commonly said that the cli- 

 mate of the Great Plains region is 

 changing and becoming drier and the 

 same is popularly supposed to be true 

 with regard to the rainfall of South 

 Africa. 1 But is this really so? The rec- 

 ords compiled by Mr. E. C. Chilcott and 

 Dr. L. J. Briggs of the Department of 

 Agriculture, are worthy of the close at- 



1 In the Transvaal, South Africa, the rainfall varies from 

 about 15 inches at Bloemhof to 50 inches in the Woodbush 

 Forest. The dry-land farmer in this colony has there- 

 fore a good rainfall as compared with the dry-land far- 

 mer in America. With regard to the total amount of rain, 

 the Transvaal has nothing to complain of. But it is its 

 unfortunate distribution that creates farming difficulties. 

 The only certain rainfall occurs during the period of No- 

 vember to March. Rains are indeed common in October 

 but sometimes do not come. In this part of Africa there 

 is no snow. 



93 



