OF THE MANDFACTURE OF GAS. 



»7 



Amount of carbonic acid generated by 1 volume of con- 

 densible hydrocarbons =281 volumes. 



Per owt, 

 Hence gain in iilominating power "^ 



by the employment of water gas 



And gain in oleiiant gas 170.2 cub. ft, 



Gain in quantity of gas 1246 " ** 



f 501.4 candles. 

 J 



Per ton, 

 10.028 candles 



3404 cub. ft. 

 24920 " " 



Per cent. 



88.4 candles. 



83.9 cub. ft. 

 188.2 " " 



NOTB.— The following Is the per centage composition of this extraordinary 

 cannel according to the mean of two analyses made with great care by my 

 assistant Mr. Russell : — 



Carbon 6S.34 



Hydrogen 9.12 



Oxygen 5.46 



Nitrogen 71 



Sulphur 16 



Water 64 



Ash 18.68 



100.00 



In this experiment it was found impossible to generate 

 more than one half of the requisite quantity of water gas 

 from the water retort connected with that in which the 

 cannel was distilled, and consequently another water retort 

 had to be employed ; but this, instead of pouring its gas into 

 the coal retort, delivered it directly into the hydraulic main ; 

 thus reducing the advantageous operation of the water gas in 

 rapidly sweeping out the illuminating gases from the coal 

 retort, and, in addition, preventing the removal of a consider- 

 able amount of carbonic acid, which materially diminished 

 the illuminating power, as indicated by the photometer. 



I have since had the opportunity of repeating the experi- 

 ment with a new apparatus, consisting of one coal and two 

 water retorts, both of the latter delivering their gas into the 

 lower division of the former: the other conditions of the 

 experiment were the same as before. 



