of Charcoal and Hydrogen. 173 
Tapre IV. showing the Composition of 100 Volumes of the Gas 
remaining after the Action of Chlorine on Oil Gas. 
oy, 
Tauie V. showing the Composition of 100 Volumes of the Gas 
remaining after the Action of Chlorine on Coal Gas, 
Exp. Azote. | Car. Hydr. |Carb.Oxide.| Hydr. Gas. Total. 
1 1°5 94°5 4 0 100 
2 Big 82 2 10 100 
3 2 66 14 18 100 
4 Ht) 60 12 3 100 
5 10 20 10 60 100 
It appears from the two foregoing Tables, that the portion of 
oil gas and coal gas, which is not condensable by chlorine, is in 
every case a mixed gas, consisting in most instances of carburetted 
hydrogen, carbonic oxide, and hydrogen, with a little azote, part 
of which may be traced to the impurity of the chlorine. In the 
best specimens of oil gas, the carbonic oxide is in greater pro- 
portion than in the best kinds of gas from coal, and the carbu- 
retted hydrogen is most abundant in the latter gas. This, how- 
ever, is more than compensated, so far as their illuminating power 
is concerned, by the greater richness of the aériform products of 
oil in that denser species of gas which is separable by chlorine. 
The proportion of hydrogen, both in oil gas and coal gas, appears 
to increase as they are formed at a higher temperature, and is 
always greatest in the latter portions of the gas from coal. But 
no instance has ever occurred to me of a gas obtained from oil 
or from coal, which, after the actioneof chlorine upon it, with the 
exclusion of light, presented a residuum at all approaching to 
simple hydrogen gas; nor do | believe that such a gas can be 
generated under any circumstances of temperature, by which the 
decomposition of coal or of oil is capable of being effected. 
Inferences respecting the Composition of that Part of theGas from 
Coal and Oil, which is condensed by contact with Chlorine, 
When a given volume of a mixture of olefiant and carburetted 
, hydrogen 
