14 CLASSIFICATION OF THE PUBLIC LANDS. 



The Geological Survey has been in existence as a distinct organi- 

 zation for about 34 years. The organizations which it succeeded and 

 whose functions it continued to perform and gradually to enlarge 

 upon as new duties were given it by Congress collected engineering 

 material that was epitomized in topographic maps and geologic ma- 

 terial that appeared either as geologic maps, as reports on geologic 

 problems, or as data on the mineral resources of the Territories. 

 Early in the Survey's history the necessities of its geologic work 

 required the organization of a topographic branch for the prepara- 

 tion of base maps. Although these maps were intended to serve 

 primarily as bases on which to delineate and present geologic mate- 

 rial, they have proved to be of great value for other and wider uses. 

 Not the least of these uses is that to which they are put in land 

 classification. The thousands of maps issued are graphic engineer- 

 ing reports on the physical and cultural features of the areas they 

 represent. They are essential to the study of drainage areas, irriga- 

 bility of lands, possible power development, and rights of way, and 

 supplemental sheets now prepared give additional data on the dis- 

 tribution of timber and of springs, of desert and of grass land, and 

 of cultivated and irrigated areas. 



On March 20, 1888, Congress, by joint resolution, directed the Sec- 

 retary of the Interior, through the United States Geological Survey, 

 to make a special investigation of the practicability of constructing 

 reservoirs for the storage of water in the arid regions of the United 

 States. This work was supported for a time by appropriations but 

 was later discontinued by Congress after many raservoir sites had 

 been examined and segregated and a number of reports valuable in 

 the classification of the lands of the arid regions had been published. 



After the irrigation survey was abolished the division of hy- 

 drography was organized within the Geological Survey, at first as 

 a part of the topographic branch and later with special small appro- 

 priations, its purpose being to continue that part of the work of the 

 irrigation survey that involved the study of the available water 

 resources of the Western States and Territoijgas. As the value of 

 this work to reclamation became manifest, Congress responded by 

 increasing the amount of the funds annually available for this pur- 

 pose until in 1903 they reached the sum of $200,000 a year. 



On June 17, 1902, the reclamation act (32 Stat., 388) was passed. 

 This act represented the culmination toward which the work of the 

 division of hydrography had up to that time been tending. That 

 work gave definite information as to available supplies of water and 

 the lands -on which the water could be used. The reclamation act 

 authorized the construction of works for the application of these 

 waters and the reclamation of the tributary lands. But the reclama- 

 tion fund is not available for general studies of water supplies ; it can 



