524 
DR. H. DEBUS OR THE CHEMICAL THEORY OF GUNPOWDER. 
Until about the year 1856 the metamorphosis of gunpowder was represented in 
chemical text-books to take place according to the equation 
2KN0 3 +3C+S=K 3 S+N 2 +3C0 2 
This equation is obviously not correct, because besides sulphide, also sulphate and 
carbonate of potassium are formed. 
After the publication of Bunsen’s and Schischkoff’s* classical investigation in 
1857, the incorrectness of the equation was generally recognised, and the view 
expressed that the explosion of gunpowder could not be represented by a chemical 
equation on account of its complex nature. Passing by for the present the papers 
published between the years 1858 and 1874, I propose to take at once into considera¬ 
tion the most recent and important investigation by Noble and Abel;+ I do so 
because we receive from the pages of their papers a very complete account of our 
present knowledge of the combustion of gunpowder. 
Five different descriptions of powder were used in their experiments. 
1. Pebble powder (P.); 2, Bifle large grain (B. L. G.); 3. Bide fine grain (B.. F. G.); 
4. Fine grain (F. G.); and 5. Spanish pebble powder. 
The first four descriptions were manufactured at Waltham Abbey. 
It will be convenient for the purposes of reference to give in the following table the 
composition of these pow T ders. 
Table I.—Showing the composition of the powders used by Noble and Abel. 
Constituents of 
powder. 
Powders from Waltham Abbey. 
Spanish. 
P. 
k. l. a. 
E. F. G. 
F. G. 
Saltpetre .... 
Potassic sulphate . 
Potassic chloride . 
Sulphur .... 
Is f Carbon , 
8 J Hydrogen . 
J 1 Oxygen . . . 
O [Ash .... 
Water. 
74-67 
0-09 
10-07 
12-120 
1*45 U 4 ’ 22 
0-23 J 
0-95 
74-95 
0-15 
* 10-27 
10-860 
1*9 \ 1352 
0-25 J 
1-11 
75-04 
0-14 
’ 9-93 
10-670 
1 14-Q9 
2-66 ( 1 y 
0-24 J 
0-80 
73-55 
0-36 
' 10-02 
11-360 
0-49 1 -u.sn 
2-57 r 459 
0-17 J 
1-48 
75-30 
0-27 
0-02 
12-42 
8-650 
P68 11134 
0-63 J 
0-65 
Noble and Abel burnt from 100 to 700 grms. of powder in hermetically closed 
steel cylinders. J The analyses of the products of combustion obtained in 31 experi¬ 
ments have been published, and of these it will be desirable to reproduce a few 
representative cases in Table II. 
* Pogg. Ann., Bd. cii., p. 321. 
t Phil. Trans., Yol. 165 (1875), p. 49, Yol. 171 (1880), p. 203. 
+ Ibid., Vol. 165, p. 61. 
