NOTES IN REGARD TO EFFICIENCIES OF LUMINOUS 

 ' FLAMES. 



BY G. W. STEWART. 



(Abstract.) 



An investigation of the efficiency of luminous flames would be of 

 interest. Results obtained incidentally were studied, showing that a 

 cylindrical acet.ylene flame is not so efficient as a flat acetylene . flame 

 when judged by the proportion of its radiant energy that is visible. 

 The amount of visible radiant energy that a given quantity is able to 

 furnish should also be considered. Experiments with a flat kerosene 

 flame show a height of flame at which the candle-power-hours-per-gram 

 is a maximum. The problem of obtaining the most efficient flame, in 

 the broadest sense, is complex. It is advisable to get the temperature 

 of the incandescent particles as high as possible, and also to get as 

 many of them per gram of the illuminant as possible. Both of these 

 factors depend upon the shape of the flame. 



