





Vol. at 0° 



Volume. 



Pressure. 



Temp. 



and 1 metre < 



159-38 



0-3144 



19-8 



46-72 



238-48 



0-4108 



19-4 



87-75 



293-77 



0-4436 



18-7 



121-98 



248-16 



0-3954 



19-1 



91-71 



181-12 



0-3504 



19-5 



59-19 



251-65 



0-4344 



21-6 



101-32 



174-85 



0-3389 



20-4 



55-15 



the Combustion of Gun-cotton and Gunpowder. 271 



Combustion Analysis. 



Original volume. . . 

 After addition of air . 

 After addition of oxygen 

 After explosion . . 

 After absorption of CO 2 

 After addition of H 

 After explosion. . . . 



The quantity of carbonic acid obtained from the absorption 



analysis =19*13. The nitrogen found by known methods is 



11-37 volume. The combustible gases are determined, by the 



formula already mentioned in the case of the analysis in the 



Torricellian vacuum, as 



op _p 



Carbonic oxide =F ] - \ =26-01, 



o 



2P — P 



Marsh-gas = — ~ =6*51, 



Hydrogen = P-P 1 = 2'83; 



in whichP = 35-35 ; 'P 1 = 32-52, P 2 =27'44. The gun-cotton used 

 in the analysis corresponded to the formula C 24 H 17 N 5 38 , from 

 which the water which cannot be directly determined, as well as 

 the eliminated charcoal, may be found. Hence the mixture of 

 gun-cotton gases consists of — 



By volume. By weight. 



Carbonic oxide . 



28-95 



29-97 



Carbonic acid . 



20-82 



33-86 



Marsh-gas . . 



7-24 



4-28 



Hydrogen . . 



316 



0-24 



Nitrogen . . 



12-67 



13-16 



Carbon . 



, 1-82 



1-62 



Aqueous vapour 



. 25-34 



16-87 



100-00 100-00 



As previously mentioned, the bursting vessels were filled with 

 10 grammes of cotton, which, by an accurate measurement, was 

 found to yield a quantity of gas of 5740 cubic centims. at 0° 

 and 1 metre pressure. The contents of the mortar at 16° and 

 0-7382 metre pressure amounts to 5292 cubic centims.; the 

 quantitity of gas issuing at this pressure amounted to 2939 cubic 

 centims. ; hence 10 grms. gun-cotton yielded 8231 cubic cen- 

 tims. at 16° and 0*7382 metre pressure. If the quantity of gas 



