﻿Acetylene. 101 



enriched by acetylene. Water gas has little illuminating 

 power and requires to be enriched by passing petroleum 

 oil into the retorts during the manufacture, and it is only 

 when water gas has already been brought up to a certain 

 candle power that acetylene gas can be mixed with it 

 without losing its effectiveness as an illuminant ; so that 

 it cannot be used as a substitute for petroleum to enrich 

 crude water gas. 



There is no apparent reason a priori why an admixture 

 of a combustible gas should deprive acetylene of its illu- 

 minating power, and it is interesting to examine separately 

 the effect of each one of the constituents of water gas 

 to see which one has this property. 



Brookline gas, besides 16°/^ of illuminants derived from 

 oil, contains equal quantities (about 26°/^) of hydrogen, 

 marsh gas and carbonic oxide. If each one of these is 

 burnt separately with acetylene it appears immediately 

 that it is the carbonic oxide which renders the acetylene 

 non-luminous. Ammonia also has a singular effect upon 

 common gas and upon acetylene, nearly destroying the 

 lighting power and giving a beautiful faint purple flame 

 with curious marked fringes, but ordinarily only traces 

 of ammonia are contained in gas. Nitrogen has much 

 less effect than ammonia or carbonic oxide in destroying 

 the illuminating power of acetylene. 



The preceding statements tend to show that a summary 

 of the qualities of acetylene gas, as compared with com- 

 mon gas, must comprise other data beside the measures of 

 candle power, and I have endeavoured to point out some 

 of the peculiar properties of the new light which are 

 advantageous. The price and the taste of the consumers 

 must decide the question of competition. 



The gas of small towns is usually poorer in quality and 

 higher in price than in large towns, and perhaps the 

 opportunities for the introduction of acetylene are great- 

 est in this direction. Consumers may be willing to pay 



