TRANSACTIONS OP SECTION C. 395 



THURSDAY, SEPTEMBER 7. 



Joint Meeting with Section B. 



Diacussion on the Investigation of the Chemical and Geological 

 Characters of different varieties of Coal, with a view to their most 

 effective utilisation as fuel, and^ to the extraction of bye-products. 



Professor G. A. Lebotjr, in opening the discussion, dealt with the various 

 aspects from which coal may be studied, and showed that, while certain of 

 these fall within the province of the geologist alone, any satisfactory classifica- 

 tion of the various types of coal, and the elucidation of the varying characters 

 of seams as traced from place to place, can be achieved only by the close 

 co-operation of geologists and chemists. 



Professor W. A. Bone briefly summarised the limited knowledge so far 

 attained regarding the chemical constitution of coal, pointing out that the great 

 bulk of the analyses hitherto made were directed merely to estimation of the 

 fuel value of samples. In his opinion no great progress was likely to be made 

 except on the lines of some well-considered scheme of research in which the 

 various workers would find their place and collaborate. 



Professor Kendall addressed himself particularly to the question of the 

 nature and origin of the ash in coal-seams. He recognised three sources of the 

 mineral matter: (1) the residue of the mineral constituents of the plants; 

 (2) detrital mineral matter; (3) the calcite, iron-pyrites, &c., segregated as veins 

 in the seams. It was shown that the different modes in which these several 

 types of ash are distributed in the coal are of great economic consequence, some 

 being separable, others inseparable. The bearing of ash on the mode of origin 

 of the coal was also discussed. 



Dr. Dtjnn gave some account of the highly variable chemical nature of the 

 ash of coals. He dwelt on the necessity for the analysis of coal-samples 

 specially selected with a view to their suitability as bearing on the geological 

 history of the deposit, for the purpose of arriving at a philosophical theory of 

 coals and their classification. The work and expenditure involved would be such 

 that the matter could only be dealt with on a national basis. 



Professor Bedson drew attention to the reports of a Committee of Section B, 

 published in the Transactions of the Association in 1894 and in 1896, dealing 

 with the action of various solvents on coal. Though some further progress had 

 been made on these lines we were still lacking exact information as to the 

 natures of the substances dissolved and of the undissolved portions. 



Mr. D. Trevor Jones and Dr. R. V. Wheeler presented a report on the 

 chemical constitution of coal. The coal conglomerate may be resolved into 

 cellulosic and resinic portions, the former containing molecules with the furan 

 structure and yielding phenols on distillation. The resinio derivatives contain 

 compounds in which alkyl, naphthene, and unsaturated hydroaromatic radicles 

 are attached to larger and more complex groupings. Under the influence of 

 pressure the bulk of the resinic derivatives have become highly polymerised. 

 The oxygenated resinic derivatives are chiefly oxides, probably cyclic oxides ; 

 esters, lactones, anhydrides, acids and ketones are absent or present only in 

 small quantity. Hydrocarbons exist in the resinic portions of coal ; saturated 

 hydrocarbons (paraffins) are, however, present in small quantities only. The 

 temperature to which coals have been subjected must have fallen short of 

 300° C. 



Dr. Marie C. Stopes dealt with the palaeobotany of coal in relation to 

 chemical constitution. It was well known that sufficiently thin sections of coal 

 showed themselves under the microscope to have been formed from a variety of 

 plant Tissues, and on the analogy of living plants it was therefore to be pre- 

 sumed that a corresponding variety of chemical substances contributed to the 

 formation of the coal. Living vegetable tissues could by no means be simply 



