THE UNITED STATES GEOLOGICAL SURVEY. 487 



tlie four sheets before him the geologist, mining engineer, Land- 

 owner, or other inquirer has in view in graphic form all that the 

 geologist can tell him of the area. A general text accompanies 

 the folio ; and, when considered necessary, a full, detailed descrip- 

 tion will be published in the form of a bulletin. This is as far as 

 the director of the survey considers that he is legally authorized 

 to go in the preparation of a geologic map. On the scale now 

 used this map will require many years for its completion. Its 

 value depends upon its thoroughness, and it is thought that qual- 

 ity, up to the scale adopted, is to be considered before the ques- 

 tion of area. The standard adopted is to do the field work up to 

 and beyond the scale of the map, and to represent on the map all 

 that the scale will permit. The result thus far is shown in the 

 folios published, and the folios of the future will prove the qual- 

 ity of the work now being done. Cost and practical working 

 methods limit the ideal perfection of field work and of the result- 

 ing maps ; but in all cases the ideal standard will be aimed at, 

 and the attempt made to present the best results obtainable under 

 the conditions surrounding the work. 



Economic Work. Some one has said that utility is the bane 

 of science, and a greater man has written that Philosophy is 

 never more exalted than when she stoops to minister to human- 

 ity. Geology is essentially practical in many of its branches, and 

 thus commends itself to those interested in the material welfare 

 of individuals, communities, and nations ; and, at the same time, 

 its great problems concerning the history of the evolution of the 

 earth and of life, including man, command the attention of in- 

 telligent mankind. In its economic aspect the Geological Survey 

 touches the interests of the people in many and varied ways. 

 Human endeavor is limited to the surface of the earth and its 

 immediate underground resources, and whatever is of assistance 

 here is an aid in the development of the higher material civiliza- 

 tion. 



In the first place, good topographic maps are essential. They 

 are needed in the construction of roads of all kinds, and in prob- 

 lems of water supply and drainage. In all future military opera- 

 tions such maps will be of service. As a basis for representing 

 the distribution of mineral resources they can not be dispensed 

 with, and in all investigations relating to the surface of the earth 

 they are of great value. 



Mineral Resources. The organic law of the survey provides 

 that the director shall have charge of the examination of the min- 

 eral resources and products of the national domain. This has 

 been interpreted to mean a statistical examination of the products 

 from the mineral resources, and a geologic examination of their 

 occurrence and character. The former has led to the compilation 



