CALORIFIC POWER OF FUELS. 



Composition of gas : 



CO, ........................ 8.5 percent. 



Excess of air ................ 53.4 



Nitrogen and residue ......... 38. 1 



CO 2 from the combustion .............. 0.070 gram. 



Equivalent to carbon .................. 0.019 " 



By the analysis of the gases and that of the coal the 

 quantity of air consumed was calculated. Knowing the 

 volume of air used for the coal, its composition, and the pro- 

 portion of carbon as black in the gases, the loss due to such 

 formation was calculated. 



Under the most unfavorable conditions for feeding the 

 air, the loss due to formation of black does not exceed 2 per 

 cent, even with smoky coal. Ronchamp coal gave the fol- 

 lowing results : 



Feeding 240 cubic feet of air per pound of coal gave a 

 gas containing 8.5 per cent of carbonic acid, excess of air 53 

 per cent, and loss of carbon as black 0.485 per cent. 



Feeding 112 cubic feet of air per pound of coal gave a 



