APPENDIX 



NOTE AS TO METHODS OF IRRIGATION 



To those who are unfamiliar with the life of the arid region 

 the actual process of irrigation seems a deep mystery. They 

 regard it as an effort to overturn the laws of nature, and 

 think it must be accompanied by a struggle as severe as it is 

 inscrutable. But irrigation is, after all, a perfectly natural, 

 and even a familiar, process. The man who waters his plat 

 of grass and the woman who waters her door-yard pansies 

 are irrigators in a rude and humble way. The citizen who 

 grumbles at the sight of withered lawns in a public park 

 during a dry summer yearns for irrigation without knowing 

 it. A generation which has harnessed the lightning should 

 see nothing incongruous in the ancient expedient of storing 

 the rain and distributing it to meet the varying needs of 

 plants which nourish human life. 



The control of water for irrigation in the West presents 

 about the same problems to the engineer as the control of 

 water for domestic purposes in large cities and towns. The 

 water must be diverted from a flowing stream at a level suf- 

 ficiently high to command the territory to be irrigated ; or it 

 must be impounded in reservoirs at a season of floods or un- 

 usual flow, such as occurs everywhere when the ice and snow 

 are melting ; or it must be sought in the bowels of the earth 

 by means of wells and lifted to the surface by pumps, except 



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