﻿. Acetylene. 97 



usually willing to take the pains to get the best burners, 

 as the following experiment will show. 



No. 2 is a gas burner 'taken off the pipes in the Tech- 

 nology building and represents the average condition of 

 burners in dwellings. About one-half the illuminating 

 power of the gas is lost in this burner, and few people 

 think of having the burners changed when they become 

 inefficient. 



If I put a globe over the burner, about half the light is 

 absorbed, so that with a bad burner and with a milk-glass 

 globe we pay about four times as much as need be for 

 light ; but the use of a globe is often necessary for com- 

 fort. The acetylene gas gives a different colored light, 

 and I thought it might pass through the globe in larger 

 proportion, but on measuring the candle power I found 

 this was not the case. Perhaps a globe can be found that 

 wdll especially suit acetylene light. 



An important question then is to be answered before 

 we can compare the lighting power of gas and acetylene. 

 Is an acetylene light more tolerant of lack of care in the 

 burners and of variations in the pressure than is the case 

 with common gas ? The most superficial observation 

 shows that the two gases must be burnt in a very differ- 

 ent way. 



Gas burnt in an acetylene jet gives less than one-tenth 

 of its true lighting power, and acetylene burnt in a com- 

 mon gas burner gives a yellow, smoky flame, and when 

 turned down to a small flame it deposits soot on the jet, 

 clogging the burner, if the opening consists of a straight 

 slit. Even the very fine fishtail burners with a straight 

 slit intended for oil gas suffer from this defect when the 

 acetylene flame is turned down. 



It appears then from the last experiments that the 

 choice of burner and the mode of using it are very 

 important factors in determining the value of any kind 

 of illuminant, and hundreds of pages have been pub- 



7 



