1881.] 



President's Address. 



65 



flame in the safety-lamp, and yet the presence of dust in suspension 

 will cause rapid ignition, or even explosion, in a degree varying with 

 the proportion of gas and the velocity of the current. Dust was 

 employed from different parts of the works of several collieries where 

 it was suspected that this agent had borne a serious part in intensi- 

 fying and spreading explosions ; and it was found that some of the 

 varieties were far more sensitive than others. Certain kinds of dust, 

 in themselves perfectly non-combustible, were similarly tested, and 

 proved to have an analogous effect in promoting explosion, even when 

 the percentage of gas was exceedingly small. 



It is obvious from these facts that under certain conditions it is 

 very important that a satisfactory indicator of minute proportions of 

 fire-damp should be employed ; and the further experiments proposed 

 to be carried out by the Commission will include a particular inquiry 

 into this subject. 



The question of the feasibility of the introduction of the electric 

 light into the workings of a colliery has been partially solved. The 

 Stanton Coal and Iron Company were induced by the Commission to 

 make a trial of Mr. Swan's lamps in their Pleasley Colliery near 

 Mansfield. Not only the inset and main road, but some of the " long- 

 wall " faces of work, were brilliantly lighted in this manner. A 

 second experiment of the same kind has been carried out at the 

 Earnoch Colliery near Hamilton. 



The use and abuse of explosives in mining operations has in the 

 last few years formed a subject of much inquiry, especially with 

 reference to the firing of shots in coal-seams liable to be invaded by 

 fire-damp. A return to mere wedging in all cases, as proposed by 

 some officials, would be to ignore the advance of science as well as the 

 necessities caused by competition; and the Commission hopes by 

 further examination, and especially by practical trials, to contribute 

 useful information to the solution of a difficult but important question. 



Among the applications of scientific apparatus, the employment of 

 the ingenious protected lime-light lamp, and of the portable breathing 

 arrangement of Mr. Fleuss, during the operations for re-opening of 

 parts of the Seaham Colliery, deserves especial notice. 



On the motion of Sir Frederick Bramwell, seconded by Dr. Allman, 

 it was resolved : — " That the thanks of the Society be returned to the 

 President for his Address, and that he be requested to allow it to be 

 printed." 



The President then proceeded to the presentation of the Medals : — 



The Copley medal has been awarded to Professor Karl Adolph 

 Wurtz, For. Mem. R.S. Professor Wurtz has, for many years past, 



VOL. XXXIII. F 



