582 
DR. H. DEBUS ON TUE CHEMICAL THEORY OF GUNPOWDER. 
carbonic acid which is developed by the combustion of a mixture the composition of 
which is represented by the coordinates of a point P, we have to draw through P a 
line parallel to D V or G H, and determine the length of the ordinate of the point 
of intersection with the side B C; this length is equal to the number of molecules 
of carbonic acid, because for all mixtures represented by the points of the side B C, 
the number of molecules of carbonic acid produced is equal to the number of atoms of 
carbon the mixtures contain. 
We will now proceed to determine, by aid of the method just explained, the quanti¬ 
ties of the products of combustion of a mixture the composition of which is represented 
by the coordinates of the point B on D V, y=16, z=5. A line drawn through B 
parallel to D C intersects D B in the point S; the abscissa of S=3, hence 3 mols. of 
potassic sulphate are produced. 
A line drawn through B parallel to B C, cuts the side D B, in F; the abscissa of 
F=4; 8 — 4=4; hence we obtain 4 mols. of potassic carbonate. 
A line through B parallel to D B, intersects D C, in point U; the abscissa of U=2; 
f=l; hence 1 mol. of potassic disulphide is formed. 
B is a point of D V, the ordinate of V, y, =12, hence we have 12 mols. of carbonic 
acid. 
Nitrogen is for all mixtures a constant = 8N 3 , therefore the equation for the meta¬ 
morphosis of a mixture, the composition of which is expressed by the coordinates 
of the point B is : 
16KN0 3 + 16C+5S=4K 2 C0 3 +3K 2 S0 4 +K 3 S 2 +12C0 3 -f- 8N 2 
The great advantage of the geometrical construction of the coefficients of equation 
(XIII.) consists in this, that we can at once ascertain by an inspection of figure BCD, 
the influence of all possible variations of the quantities of carbon and sulphur in 
given mixtures, upon the proportions of the corresponding products of combustion. 
Similar considerations enable us to find the quantities of gas and heat. 
If we add the constant 8 for nitrogen to the number of molecules of carbonic acid 
determined as previously explained, we obtain the total number of gas molecules 
produced by the combustion of a mixture represented by the coordinates of a given 
point. 
The heat generated is found by equation (X.). 
For powders which shall produce by their combustion the same amount of heat, 
we have : 
l'92y=— z-\- 
1827154—c 
8788 
for which we may adopt without serious error 
1827154—c 
8788 
(XVII.) 
