358 ILLINOIS STATE ACADEMY OF SCIENCE 



whereby the slow effect by conductivity is replaced by 

 the relatively quick procedure of preheating the coal, 

 thus securing autogenous chemical reaction throughout 

 the mass. 



For the present at least we are content to leave the 

 ultimate goal of fuel gas and stop at the coke stage, 

 especially in view of the fact that the coke produced in 

 this manner comes into the class of smokeless fuels with 

 combustion characteristics quite comparable to the 

 anthracite or semi-anthracite type. 



