210 ILLINOIS STATE ACADEMY OF SCIENCE 



7. Agricultural Development. 



Maps showing the character of the soil and the con- 

 figuration of the ground indicate to the settler the desir- 

 ability or undesirability of any particular piece of land 

 for farming, and so assist him in its proper cultivation. 

 Hence soil maps are of increased value where printed on 

 topographic maps. 



8. Development of Mineral Resources. 



Geological study showing the mineral resources of a re- 

 gion must be preceded by a topographic map of the area on 

 which to plot the field data. Many promising mineral areas 

 in the west now await topographic mapping for their de- 

 tailed study and development. 



9. Utilization of Timber Resources. 



The economical examination of timber bodies, the lo- 

 cation of logging railways and tramways, the estimation 

 of costs of logging operations, the determination of areas 

 that can be logged from different bases of operation, the 

 selection of lines of communication, lookout points, fire 

 lines, etc., are all dependent upon a knowledge of the topo- 

 graphy as well as the forest cover of the region considered. 

 Hence a topographic map is fundamental to the wise ad- 

 ministration of forested areas, decreasing the cost and 

 materially increasing the efficiency of forest management. 



10. Utilization of Grazing Resources. 



Efficient administration of grazing lands requires map- 

 ping of the topography and vegetative cover, in order that 

 the kind of stock and number of animals that can be car- 

 ried may be determined, and that appropriate seasonal use 

 of the range may be planned. Such maps are invaluable 

 aids in range management. 



11. Educational Uses. 



In the study of physical geography, topographic maps 

 of the U. S. Geological Survey are of widely recognized 

 value. To the trained reader such maps give a great 

 variety of information such as suggestions of climate, 

 character of underlying rock, industries of an area and 

 geologic history. 



