OUR COAL SUPPLY 



111 



being wasted than is being used for the benefit of mankind. 

 The two chief sources of loss are: 



1. Only about one-half of the coal is being removed from 

 the mine; the other half is being left in such a condition that 

 it probably can never be recovered. 



2. We have seen in the preceding pages of this chapter, 

 and shall see still more clearly in Chap. X, that only a small 

 portion of the energy in the coal burned is now being utilized. 



126. The Coal Fields of the United States. The map, 

 Fig. 85, shows the location of the more important coal fields 



FIG. 85. Distribution of coal fields in the United States. 



of the United States. The large eastern field extending from 

 Pennsylvania to Alabama yields chiefly anthracite, semi- 

 anthracite and semi-bituminous coals. The central fields, 

 consisting of the Illinois, Indiana, Kentucky, Iowa, and Mis- 

 souri fields yield chiefly bituminous and cannel coals. The 

 large northwestern field of the Dakotas, Montana, and Wyom- 

 ing yields bituminous and lignite coals. The fields of Colorado 

 yield bituminous and semi-anthracite coals (see Table III, 

 page 95, Composition of Solid Fuels, for the distinction in 

 different kinds of coals). 



