534 
DR. H. DEBUS ON THE CHEMICAL THEORY OF GUNPOWDER. 
in contact in a fluid condition at a high temperature. Amongst these products we 
have not, as is usually assumed, potassium monosulpliide, but disulphide, free sulphur, 
and potassium carbonate. But a mixture of polysulphides of potassium and potassium 
carbonate at a bright red or a white heat has a most powerful corroding effect upon 
metals. It is well known that the celebrated Stahl was of opinion that Moses had 
dissolved the golden calf of the Israelites by means of a polysulphide of potassium. 
“ And he took the calf which they had made, and burnt it in the fire, and ground it 
to powder and strewed it upon the water, and made the children of Israel drink of it.” 
—(Exod. xxxii. 20.) 
Sulphur and ash of wood were known to the Jews, and these, at a high temperature, 
form liver of sulphur, capable of dissolving gold. The affinity of iron for sulphur is 
very strong. We may expect that, according to temperature, pressure, time of cooling, 
and last but not least, the condition of the surface of the cylinder, more or less of the 
sulphur of the powder would unite with the iron of the apparatus. This would have 
the same effect upon the products as if a powder with less sulphur had been burnt. 
If 400 grms. of powder of the average composition had been exploded, and 10 grms. 
of its sulphur were to unite with the iron of the apparatus, the potassium carbonate 
produced would be about 0’20 time greater than the amount obtained by the com¬ 
bustion of the same quantity of powder without this removal of sulphur by the iron 
of the apparatus. 
According to the description given by Noble and Abel of the solid powder residue, 
considerable quantities of ferrous sulphide were contained in it. Hence the variations 
in the quantities of the products of combustion of powders exploded in Noble and 
Abel’s apparatus will partly be due to the chemical action of iron and sulphur at high 
temperatures. 
It will be observed by an inspection of the equations on pages 529 and 530, that 
considerably more oxygen was found in the products of combustion than was contained 
in the saltpetre of the exploded powder. This excess of oxygen cannot have been 
derived from the charcoal, or the moisture of the powder, because if it had, equivalent 
quantities of hydrogen ought to have been liberated. Charcoal contains more hydrogen 
than is necessary to form water with its oxygen. It is this excess of hydrogen which 
is set free, or which unites with sulphur, carbon or nitrogen forming sulphuretted 
hydrogen, marsh gas, or ammonia. 
Hence, the excess of oxygen in the products of explosion must originate from some 
other source. Noble and Abel, like Linck, Kabolyi and others, adopted the method 
proposed by Bunsen and Schischkoff for the analysis of the solid powder residue. 
This method requires that the aqueous solution of the substance should be digested 
with cupric oxide in order to convert the potassic sulphide into hydrate. The question 
suggested itself whether or not oxygen from the cupric oxide had formed with 
potassic sulphide, sulphate or hyposulphite. 
27*3 grms, pure potassic hydrate were dissolved in water, which previously had been 
