PAPERS ON CHEMISTRY AND PHYSICS 



347 



COMPOSITION OF COALS 



This question was first installed, so to speak, in the 

 chemical laboratory at the University of Illinois in 1902, 

 and it is no exaggeration to say that today in this year 

 of grace, 1921-22, it is more installed than ever. The 

 slight hitch which occurred 20 years ago in the curve for 

 the output of anthracite means that for the major part 

 of that year the country at large was deprived of its 

 smokeless fuel, and dire necessity was the mother of the 

 practice of burning bituminous coal. Hence, the ques- 

 tion, ''What is coal?" 



"We have already seen that geographically the Illinois 

 fields are about midway between the deposits of the East 

 and the AVest. In a general way this is true also geologi- 

 cally. The fact is still further emphasized when we look 

 at the coals chemically. In this chart, we have average 



^600 



L 



I 



-.400 



I 



leao zees 

 Fig. 5. 



/890 I89S 1900 I905 I9/0 /9IS I920 



Growth of Coal Production since 1880. 



analyses showing the composition of three types, a low 

 volatile Eastern bituminous coal, an Illinois coal and a 

 lignite. For our purpose in this discussion it is desired 

 to call attention to one characteristic diiference only, 

 that is the shaded portion. This represents the residual 

 oxygen or "hydroxy" compounds which remain from 

 the initial organic material after all the vicissitudes of 

 decay and geological alteration have taken place. 



