3C6 



Dr. H. Debus. 



[Feb. 23, 



which are almost identical with 



16KN0 8 +21\L8C+6-63"S, 



representing the mean composition of the powders found by direct 

 analysis. 



13. An increase of pressure during combustion appears to diminish 

 the amount of carbonic oxide, and, in consequence, according to 

 equation 8, to increase the quantities of potassic carbonate, potassic 

 disulphide, and carbonic acid. These fluctuations in the quantities 

 of the products of combustion are, however, very small, and may be 

 neglected without serious error. 



14. Craig had asserted that the nature of the products of explosion 

 of gunpowder depended on the pressure developed during combustion. 

 Karolyi, in order to test this assertion, made experiments with Austrian 

 Service powder, and arrived at the conclusion that pressure had no 

 influence on the quality or quantity of the products furnished by these 

 powders. 



The experimental results of Karolyi, and the differences between 

 these results and those obtained by Noble and Abel, have enabled the 

 author to develop a chemical theory of gunpowder competent to 

 explain the observations of Bunsen and Schischkoff, Linck, Karolyi, 

 Noble, and Abel, and other investigators, and which is in harmony 

 with the thermochemical relations of the reacting substances. 



According to this theory the combustion of - gunpowder takes place 

 in two stages, one succeeding the other. The reactions of the first 

 stage cause the explosion of the powder. Gunpowders which differ con- 

 siderably in their composition are transformed during the first stage 

 according to the equation 



10KNO 3 + 8C + 3S=2K 2 CO 3 + 3K 2 SO 4 +6CO 2 + 5N 2 . . (3), 



but as it is probable that at the same time some carbonic oxide is pro- 

 duced, the following would more correctly represent the reactions : — 



16KN0 3 + 130 + 5S = 3K 2 C0 3 + 5K 2 S0 4 + 9C0 2 + CO + 8N" 2 . (4) , 



The constituents of the powder, and those of the products of com- 

 bustion are, according to equation 4, nearly in the same ratios as they 

 are according to 3. 



During the first stage of the combustion potassic disulphide is not 

 formed. 



The oxygen of the potassic carbonate, potassic sulphate, and the 

 carbonic acid, as represented by equation 3, stand to each other in the 

 most simple possible ratios, if these substances are to be produced by 

 the combustion of a mixture of saltpetre, carbon, and sulphur. In 

 other words, equation 3 represents the most simple distribution of the 

 oxygen of the decomposed saltpetre amongst the products of combus- 



