THE PROVIDENT USE OF COAL 323 



agreeable. If people were aware of the evils caused by the 

 sulphur in gas and coal, they would object strongly. 



The explanation of the absence of special complaints of 

 the quality of the gas now supplied by the gas companies is 

 that people generally are too ignorant of the subject to 

 appreciate the deterioration. If the reports which were made 

 to the London County Council by their chemist on the gas 

 supplied to the metropolis in the year or two following the 

 repeal of the sulphur compound clauses are consulted, it will 

 soon be realised to what an extent the sulphur in the gas 

 was allowed to increase. Previously no effort was spared by 

 those connected with the gas industry to remove the sulphur 

 compounds. In making the change public interests were put 

 aside for no good reason. 



It is well known that the intrinsic illuminating efficiency 

 of coal gas has been steadily reduced during the past few 

 decades. The late Sir Edward Frankland, the premier authority 

 on the subject, complained of this constantly ; his son, Prof P. F. 

 Frankland, has also frequently taken exception to the quality of 

 our modern gas supply. Burners have been improved, however, 

 while the gas has been lowered in quality, so that the public have 

 not been aware of the change ; but as a consequence they have 

 gained little from the improvements in burners. The situation 

 has been saved for the gas companies of late years by the intro- 

 duction of the Auer mantle and it has been the policy of 

 many of the companies to encourage, if not enforce, its use, 

 so that they might still further reduce the intrinsic illuminating 

 power of the gas. Those who continue to use naked flame 

 burners suffer considerably from the change. Now the lowering 

 of the calorific power of gas is being advocated, which will 

 involve the supply of a vastly larger quantity and the use of 

 a large radiant for illuminating purposes. 



To me it seems that the tendency is both wrong and 

 impolitic. We need to copy the electric light and the acetylene 

 lamp and use a small rather than a large radiant. And if gas 

 is to be used more largely for domestic purposes, we shall 

 need to minimise the size of the gas mains as far as possible. 



If it be decided, on public grounds, to use gas of low intrinsic 

 illuminating power, it will be easy to produce such gas 

 economically by mixing the rich gas obtained by coking coal 



