Mathematical and Physical Papers. 



229 



For the sake of comparison of methods, we have added the results 

 of a few analyses of Kansas coals from neighboring mines, made by 

 Dr. W. R. Crane, and recorded on page 278 of volume III of the 

 University Geological Survey of Kansas. 



No. 



Name. 



J. H. Bennett Coal Company No. 1, coal . . . 

 J. H. Bennett Coal Company No. 1, dust. . . 

 Coal from neighboring mines. Weir City- 

 Kan.: 



Kansas & Texas No. 18 



Kansas & Texas No. 47 



Durkee Coal Company No. 4 



Hamilton & Braidwood No. 2 



Central Coal Company No. 5 



Durkee Coal Company No. 1 



The Excelsior Coal Company 



Average of seven 



Devlin & Miller mine No. 1, coal 



Devlin & Miller mine No. 1, dust 



Coal from a neighboring mine, Frontenac, 

 Kan 



Moisture. 



1.849 

 1.45 



3.57 

 3.16 

 2.34 

 2.63 

 3.14 

 2.57 

 2.58 



2. 



1.79 

 1.20 



3.06 



Volatile 

 and com- 

 bustible. 



40.55% 

 28.12 



36.96 

 39.21 

 36-. 88 

 38.80 

 34.87 

 36.34 

 36.73 



37.11% 



39.13 

 31.23 



35.92 



Fixed 

 carbon. 



50.25% 

 51.03 



51.84 

 53.87 

 55.69 

 53.74 

 55.39 

 54.99 

 55.02 



54.70% 



53.41 

 54.22 



54.89 



Ash. 



7.36% 

 19.40 



7.63 

 3.76 

 5.09 

 4.83 

 6.60 

 6.10 

 5.62 



5.67 

 13.35 



6.13 



In the results of our examination we would call attention espe- 

 cially to the decrease in the volatile and combustible matter and 

 the increase in fixed carbon and ash. 



The dust after the explosion is probably mingled with dust from 

 the roof and floor of the mine or it would be the best index of the 

 amount of coal consumed by the explosion. In the one case the 

 ash increased 2.35 times, and in the other 2.54. While this com- 

 parison is not accurate, it would indicate that a considerable pro- 

 portion of the finely divided carbon was oxidized in the explosion. 



The decrease in the volatile and combustible material is also in- 

 teresting, and we would mention the fact that the finely divided 

 coal is browner in color than the finely divided dust, and, also, 

 when placed on white paper, leaves a much more decided streak. 

 Experiments with regard to the action of air on the finely divided 

 dust are being carried on. 



