PAPERS OX CHEMISTRY AND PHYSICS 351 



coking and the other has distinctly coking properties. 

 We have here the first real forward step in the study of 

 the carbonization. The results obtained by these meth- 

 ods were well summarized by the late Professor Vivian 

 Lewes in his Cantor lectures delivered in London in 

 1911. He called the non-soluble, that is the non-coking 

 substance, the degradation product of celhilose or cellu- 

 losic residue, and soluble, or coking substance, he called 

 resinic material. In the light of jDresent-day studies, 

 these names are not happily chosen, but that fact does 

 not interfere with the value of the method itself. A 

 continuation of this line of investigation is being very 

 ably carried on by Professor Bone of London and by 

 Professor "Wheeler of the I'niversity of Sheffield. 



In our own laboratory at the Laiiversity of Illinois, it 

 continues to be the most prolific source of information 

 and furnishes the most numerous avenues of approach 

 to the fundamental characteristics of these two type sub- 

 stances. It is along these lines, moreover, that we have 

 made the most encouraging progress in our studies as 

 to the underlying principles involved in the carboniza-- 

 tion of coal. 



It will be altogether impossible to go into a detailed 

 discussion of the facts which have been developed, not 

 only because there are so many of them, but also because 

 there are so many which are in process of development 

 and have not yet reached full maturity, and the plucking 

 of immature fruit of this sort is not conducive to mental 

 health and tranquility. 



A few points, however, will give a general idea of what 

 has been accomplished. 



In the chart here shoA\^i, we have an illustration of 

 the two type substances, the larger amount being the 

 insoluble residue or non-coking substance and the 

 smaller portion being the so-called • resinic or coking 

 material. The amount in each sample will give also a 

 ■general idea of the relative proportion of these two sub- 

 stances as found in Illinois coals. 



Now from the discussions that have thus far been 

 presented in the literature, it would appear that the 

 soluble material at the right, Fig. 8, is looked upon as 



