270 



Mr. Dugald Clerk 



[Jan. 2y, 



Fig. 1 gives a series of such indicator diagrams by Clerk from 



gaseous explosions obtained with mixtures of air and coal gas, where 



air . ^ 



-- varies from 4 to 12. 



iMt. sees. 



Fig. 1. — Explosion in a Closed Vessel. London Gas, 1900 (Clerk). 



Analysis of Coal Gas. 



Hydrogen . . , 45-2 Carbonic oxide 



Marsh gas . . . 29 ' 9 Oxygen 



Unsaturated hydrocarbons 5 • 1 Nitrogen 



The following is a Table of the results : — 



Explosion in a Closed Vessel (Clerk 1900). 

 Mixtures of Air with London Coal Gas. 



10-3 



0-5 



10-0 



100-0 



Temp, before explosion 

 Pressure before explosion 



16^ C. 



14* 8 lbs. per sq. in. 



