IRRIGATION AND DRAINAGE 143 



day find difficult to ascribe to so remote a civilization. 

 Cities were built up and entire areas developed, whose 

 inhabitants relied solely for subsistence on these irrigation 

 works. The remains of these ancient systems can still be 

 traced in sufficient detail to give an idea of their extensive- 

 ness and efficiency. 



In America irrigation was practiced by some Indian tribes 

 (or nations) long before the earliest white man set foot on 

 the continent. In parts of New Mexico there remain to the 

 present day irrigation systems which are abundant testimony 

 to the skill and foresight of these inhabitants. Canals still 

 in a fair degree of preservation extend many miles around 

 and across plateaus, connecting the sources of water with the 

 places where it was to be applied. For designing works 

 of this sort, these aborigines possessed no instruments such 

 as we have today for the making of precise measurements. 

 They adopted the device of filling the ditches with water 

 as they dug, being guided in this way as to the route which 

 the canal was to follow. The results were ditches of marvel- 

 ously even grade. 



234. Recent irrigation. Irrigation in America under the 

 regime of the white man may be said to have begun with 

 the Mormon settlement of Utah. Smythe, in his book The 

 Conquest of Arid America, gives an exceedingly interesting 

 account of the way in which these Mormon wanderers 

 reclaimed an unpromising desert and made of it one of the 

 most fertile regions of the United States. For a full account 

 of this pioneer effort in irrigation, the student is referred to 

 Smythe's book. 



235. Reclamation service. In 1912, during the presidency 

 of Theodore Roosevelt, the United States Government for 

 the first time definitely adopted the great policy which led 

 to the establishment of the Reclamation Service. Briefly 

 stated, it was this: The Government stands ready to finance 

 and execute projects in irrigation and drainage which in the 



