DR. H. DEBUS ON THE CHEMICAL THEORY OE GUNPOWDER. 
591 
and nitrogen, and, perhaps, some carbonic oxide, but no potassic disulphide, are 
produced. 
(Jb.) A process of reduction during which carbon and sulphur left free at the end of 
the first stage react with some of the products formed during that stage; the free 
carbon reducing potassic sulphate, with formation of potassic disulphide, potassic 
carbonate, and carbonic acid; the free sulphur decomposing potassic carbonate with 
the production of potassic disulphide, potassic sulphate, and carbonic acid [equations 
(V.) and (VI.)]. 
6. The first stage of the combustion, the explosion proper, takes place with powders 
of various composition according to equation : 
10KNO 3 +8C+3S=2K^CO 3 +3K 2 SO 4 +6CO 2 +5N 3 . . . (III.) 
But as some carbonic oxide is probably produced at the same time, the following 
will more correctly represent the reactions. 
16KN0 3 +13C+5S=3K 2 C0 3 +5K 2 S0 4 +9C0 2 +C0+8N 2 . . (IV.) 
The constituents of the powder and the products of combustion are, according to 
(IV.), nearly in the same ratios as according to (III.). 
7. The oxygen in the potassic carbonate stands to the oxygen in the potassic 
sulphate and carbonic acid, respectively, in equation (III.), in the most simple ratios 
which can exist, if these substances are to be produced by the combustion of a mixture 
of saltpetre, carbon, and sulphur. In other words, equation (III*) represents the most 
simple distribution of the oxygen of the decomposed saltpetre amongst the products of 
the first stage of the combustion. And because the products are, according to equa¬ 
tion (TV.), nearly in the same proportions they assume to (III.), it follows that the 
distribution of the oxygen between potassic sulphate, carbonate, and carbonic acid, 
according to (IV.), nearly corresponds to the most simple possible distribution. 
8. If the greatest possible amount of heat is to be evolved by the combustion of a 
mixture of saltpetre, carbon, and sulphur, and if at the same time potassic sulphate, 
carbonate, and carbonic acid are to be formed in such proportions that the heat of 
formation of one of them shall stand to the heat of formation of each of the others in 
the most simple ratio, then the combustion must take place according to equation (IV.). 
The heat produced by the formation of 3 mols* of potassic carbonate stands to that 
produced by the formation of 5 inols. of potassic sulphate and 9 mols. of carbonic acid 
respectively, as 
1:2-05:1-04 
9. The ordinary gunpowders contain more carbon and sulphur than is required by 
equation (IV.). 
MDCCCLXXXII. 4 G 
