272 M. L. v. Karolyi on the Products of 



is calculated from the results of the analysis, it is found that 

 lOgrms. of gun-cotton yield 5764*2 of gases, which sufficiently 

 agrees with the quantity actually found. 



Comparing the results of the above-described analysis with 

 those of the analysis in the Torricellian vacuum, it is found 



(1) That the gases in both cases are combustible from the 

 large quantity of carbonic oxide they contain. 



(2) That the gases produced in vacuo contain a considerable 

 quantity of binoxide of nitrogen, while by burning gun-cotton 

 under appropriate resistance, the nitrogen compounds are deoxi- 

 dized in favour of the carbon in marsh-gas and of the hydrogen, 

 by which an increase in the carbonic oxide, carbonic acid, water, 

 and a separation of free hydrogen are caused. Hence it follows 

 that the red gun-cotton vapours can never occur if the entire 

 gun-cotton is burnt away at the moment in which it begins to 

 overcome the resistance offered to it. 



These facts have a practical application in the use of gun- 

 cotton to mining purposes. 



II. Analysis of the Products of Combustion of Gunpowder, 



After finding that the combustion of gun-cotton under cir- 

 cumstances resembling those which occur in mines is of decisive 

 influence on the products evolved, it apeared desirable to inves- 

 tigate the combustion of gunpowder under similar circumstances. 

 Unfortunately, since my investigations had a specifically military 

 object, I could only analyse the Austrian small-arms and ord- 

 nance powder ; hence only a superficial comparison can be insti- 

 tuted with the results which Prof. Bunsen obtained with freely- 

 burning sporting-powder. 



The combustion of the gunpowder was effected in the ex- 

 hausted mortar in the same way as the combustion of the gun- 

 cotton, with the exception that, on account of the smaller 

 action of the powder, and in order to obtain as large a quantity 

 of gas, the exploding vessels had to be larger, but with thinner 

 sides than those in which the gun-cotton was exploded. The 

 excavation in the cores was filled with meal powder. 



The composition of the two kinds of powder used for investi- 

 gation are obtained from the following analyses. 



Ordnance Powder. — 4*5487 grms. gave 3*3562 grms. saltpetre 

 and 1*1923 grm. of a residue insoluble in water. Bisulphide of 

 carbon dissolved 0-5823 sulphur. The remainder was charcoal. 



Small-arms Powder. — 8*8653 grms. contained 6*8408 salt- 

 petre : the residue of 2*0245 grms. contained 0*765 grm. 

 sulphur, and there remained 1*2595 grm. of charcoal. The 

 organic analysis of the charcoal, carefully freed from sulphur, 

 gave — 



