1894.] 



Researches on Modern Explosives. 



17 



of the permanent gases is also altered, as might be expected, there 

 being an increase in carbonic acid and decrease in carbonic oxide 

 and hydrogen. 



The similarity in the volumes of gas produced and the composition 

 of the permanent gases in the case of experiments F and G is worthy 

 of note when the great difference in the original component ingre- 

 dients of the explosives is borne in mind. 



Table III shows clearly the increase of heat due to increased per- 

 centage of nitro-glycerin, as well as the difference of heat evolved 

 from explosives containing nitro-cellulose of different degrees of 

 nitration. 



The diminution in quantity of heat (about 200 calories) which the 

 replacement of 5 per cent, of nitro-cellulose by vaseline makes is also 



very striking. 



. 



Table IV. Showing the Heat developed and the Analysis of the 

 Permanent Gas produced in a closed Vessel from which the Air 

 has not been exhausted the Explosive being in every case 

 Ballistite of Italian Manufacture. 



Traces of CH 4 were found, but in this series of experiments the quantity of this 

 gas was not determined. 



Table IV shows the part played by the oxygen of the air in the 

 bomb ; when a smaller proportion of explosive in comparison with 

 the air is present the combustion is more complete, and the heat 

 evolved is greater, and the composition of the gases is correspond- 

 ingly modified. 



In Table V the elementary percentage composition of some of the 

 explosives, along with the percentage composition of the products of 

 explosion by weight, is given. 



The composition of the samples has been calculated from the 

 " bomb " analyses ; as an example, one of the explosives and its 

 decomposition may be represented approximately by the following 

 equation. 



We have assumed the nitro-cellulose to consist of a mixture of di- 



VOL. LVI. c 



