ON THE DEVELOPMENT OF LIGHT FROM COAL-GAS. 



243 



Batwing Burners. 



It will be seen that the small quantity of gas passing throtigh No. 1 

 union-jet becomes so mixed with air that even at 0'5 inch pressure the 

 light emitted when burning 1'6 cubic feet per hour is only equal to one 

 candle, or 3-1 candles when calculated for 5 feet consumption of gas. 

 When the pressure is increased to I'S inches the results are still worse, 

 for 3' 2 cubic feet of gas per hour are burned with the production of light 

 equal to 1-2 candles, or only 1-9 candles per 5 cubic feet of gas. With the 

 larger sized union-jets the results are better, No. 6, when consuming 3-8 

 cubic feet of gas at 0*5 inch pressure giving a light equal to O'G candles 

 per 5 feet of gaa. This amount of gas— 3-8 cubic feet — when issuing 

 under 0-5 inch pressure is not mixed with so much air as the 32 cubic 

 feet issuing under a pressure of 1-5 inches from the No. 1 burner. 



The effect of the increase of pressure on the air supply, and conse- 

 quently on the light produced, is also seen in the results of the experiments 



If the result of burning 5'4 cubic feet of gas 

 k2 



with the batwing burners 



