566 
DR. H. DEBUS OR THE CHEMICAL THEORY OF GUNPOWDER. 
The mean composition of the powders of Waltham Abbey is expressed by the 
symbols 
16KN0 3 +21T8C+6-63S 
and because, during their combustion, 0'67 mol. of sulphuretted hydrogen is formed, 
there remain 
16KN0 3 +21T8C+5*96S 
for the formation of the principal products. 
But as the portion of the sulphur which has united with the iron of the apparatus 
has not been determined by direct experiment, we are obliged to form an estimate of 
its amount from other considerations. 
According to the remarks on pages 557-559, potassium disulphide is produced by 
the metamorphosis of gunpowder. The combustion of a quantity of powder con¬ 
taining 16 mols. of saltpetre produces, if we take the mean of all the experiments 
of Noble and Abel, 0‘90 mol. of K 2 S0 4 and 2T mols. of K 2 S 2 , for which quantities 
1 mol. of K 2 S0 4 and 2 mols. of K 2 S 2 have been placed in equation (II.). From this 
it follows that 5 atoms of sulphur have taken part in the metamorphosis, and that 
0'96 atom of sulphur has remained free or has united with the iron of the explosion 
apparatus. 
The experiments of Karolyi support this conclusion. The Austrian cannon powder 
containing 8 - 7 atoms, and the rifle powder 5'66 atoms of sulphur for every 16 mols. of 
saltpetre, and in the principal products of combustion of the former 5'25 atoms, and 
in those of the latter 4*89 atoms of this element were found, the rest of the sulphur 
having remained free. In spite of the great difference of the amounts of sulphur in 
the two descriptions of powders, we find in their products of combustion, for 16 mols. 
of decomposed saltpetre, almost the same quantity of sulphur, 5 atoms, in both cases. 
In Noble and Abel’s experiments the sum of the sulphur in the sulphate and 
disulphide is likewise equal to 5 atoms. From this equality we may conclude that in 
Noble and Abel’s, as in Karolyi’ s experiments, during the first stage of combustion, 
or the stage of explosion, the powders were transformed according to equation (IV.), 
page 553, and that 5 of the 5'9 6 atoms of sulphur entered into combination. The 
remaining 0‘96S should, during the second stage, have reacted with potassic car¬ 
bonate according to equation (V.), page 559, but as this reaction appears not to have 
occurred, we may conclude, with great probability, that the 0'96 atom of sulphur 
united with the metal of the apparatus. 
Since in Noble and Abel’s experiments all the powder introduced into their 
apparatus was completely burnt, and as the sum of the weights of the secondary 
products, after deducting the sulphuretted hydrogen, is very small, and finally, 
because potassium, oxygen, and carbon in the principal products of combustion 
occur almost in the same proportions as in the saltpetre and charcoal of the original 
powder, we can substitute for x and y, in equation (VIII.), the values derived directly 
from the composition of the powder. 
