APPENDIX 



extended in circles around each tree, but the water is never 

 allowed to touch the bark. This method is, perhaps, better 

 adapted to the general needs of the arid region than the 

 more expensive plan of the Californians. It is interesting to 

 note that the modern New Mexico method was developed in 

 the midst of Indian and Spanish settlements, which still pur- 

 sue the methods of antiquity without the slightest abatement 

 of their evils. 



One of the most interesting results of irrigation, in a social 

 and economic way, is its influence upon the density of popu- 

 lation. The densest population in the eastern States obtains 

 in Rhode Island, where there are two hundred and seventy- 

 six persons to each square mile. In a representative locality 

 of southern California, which is in the midst of the older 

 settled irrigated districts, there are five hundred persons to 

 the square mile, practically all of them engaged in horticult- 

 ure by means of irrigation. The Nile lands of Egypt sup- 

 port a population of twelve hundred and twenty-seven persons 

 to the square mile. There is, therefore, no risk whatever in 

 predicting that the arid lands of the West will ultimately 

 sustain much the densest population in the United States. 



While the perfect conditions for the irrigation industry 

 exist only in an arid land, there is no doubt that the same 

 methods can and will be used largely in the eastern portion 

 of the United States. There is seldom a year when large 

 districts east of the Mississippi do not suffer heavy losses 

 from the lack of rain at the time when it is needed. What 

 irrigation can accomplish under such conditions has been 

 strikingly illustrated by Dr. Clarke Gapen, Superintendent of 

 the State Insane Asylum at Kankakee, Illinois. This gentle- 

 man became convinced that if he could control the moisture 

 during the dry period of the Illinois summer, he could readi- 

 ly produce, on the farm operated in connection with the pub- 

 lic institution, the large quantities of late vegetables which 



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