THE RAIN BELT EXTENSION. 123 



Professors Aughey and Wilber, of the University of Nebraska, 

 declare that Western Nebraska and Eastern Wyoming will show a steady 

 climatic change. 



Professor Wilber says he has talked with hundreds of fanners upon 

 the frontier, whose uniform testimony was to the effect that there was a 

 gradual development of the resources of the soil, by the increase of 

 moisture in its various forms, which follows upon cultivation. 



More recently, Mr. Harrington, editor of the American Meteorological 

 Journal, in quite an elaborate discussion of this question concludes that 

 " increased rainfall occurs along the line of largest immigration to the 

 plains, and as the invasion is still going on on an enormous scale, it is 

 hardly safe to say that the attendant meteorological change will not con- 

 tinue farther." 



Whether or not these deductions will antagonize the scientific 

 hypothesis, that this planet of ours is gradually approaching the sup- 

 posed rainless condition of the moon, or whether, even if established 

 beyond a question, they would be regarded in the nature of " local oscil- 

 lations " that are only apparent exceptions to the hypothesis is a 

 matter that perhaps does not immediately concern practical people. The 

 question is, what is actually bringing about this increase of rainfall? 

 Probably the two main causes are, first, the subjection of a vast territory 

 to rapid and continuous cultivation, by constant stirring of the soil and 

 uprooting the native grasses, thus overcoming the resistence to free capil- 

 lary action ; and second, the extensive planting of timber and smaller 

 growths, both of which, on a large scale, tend to increase atmospheric, as 

 well as terrene humidity, and consequent precipitation. Another influ- 

 ence that may have a bearing on results is the increased humidity of 

 Western winds, caused by evaporations from extended irrigation districts 

 along the base of the Rocky Mountains. But whatever the true causes 

 are, results will be of deep interest to all the country likely to be effected. 



