CAPTAIN NOBLE AND MR. F. A. ABEL ON FIRED GUNPOWDER. 219 
It will be remembered that a special method of collecting for analysis the solid 
products furnished by these powders was adopted, with the object of altogether 
guarding against the possibility of accidental conversion of sulphide into hyposulphite. 
The analytical results show that the chief differences between the results of explosion 
of the sporting powder (in 30 per cent, space) and of the It. F. G. powder (in 
70 per cent, space) consisted, as regards the gaseous products, in the slightly higher 
proportion of carbonic anhydride and in the very decidedly larger amount of marsh 
gas furnished by the former, and, as regards the solid products, in the higher 
proportion of sulphide and lower proportion of hyposulphite ; the quantities of these 
constituents of the residue are very similar to those found in the ft. L. G. residue 
exploded in 80 per cent, space. 
The gaseous and solid products of explosion of the mining powder differed very 
greatly, as was anticipated, from those furnished by all the other powders, as regards 
their proportions. The carbonic oxide was double the highest amount furnished by 
any of the other powders, while the carbonic anhydride, which in the three series of 
experiments ranged from 45 to 53 per cent, of the total volume of the gases, amounted 
only to 32 per cent., the two gases existing in about equal proportions. Marsh gas and 
hydrogen were present in unusually high proportions, and the sulphuretted hydrogen 
amounted to 7 per cent., being nearly double the highest proportion found in all the 
other experiments. The solid residue presented very interesting points of difference. 
The potassium carbonate was, as might have been anticipated, comparatively small in 
amount (though some of the experiments with F. G. powder gave similar results in this 
respect), but there was only 0‘5 per cent, of sulphate formed, wdiile the monosulphide 
amounted to 33 per cent, of the solid residue, and the free sulphur to nearly 13 per cent. 
Federow’s experiments are the only ones in which so high a (and indeed a somewhat 
higher) percentage of sulphide is recorded, and among the several experiments 'with 
It. L. G. powder, in which only small proportions of sulphate were formed, there was 
only one residue in which the free sulphur was as high in amount as that formed in 
the mining powder residue. It w 7 ill be seen that the hyposulphite amounted to nearly 
6 per cent.: 2 per cent, more than was furnished by the sporting powder under precisely 
similar conditions of experiment, and double the smallest amount formed in any of the 
series of experiments, conducted without the very special precautions which were 
applied in dealing with the residue of the powder under discussion. The ammonium 
sesquicarbonate was considerably higher in amount than in any other experiments 
(though still much below the amounts found by Karolyi and Linck), and the 
potassium sulphocyanide amounted to 3 per cent., or about five times the amount 
found in any other experiments excepting that of Linck. 
Lastly, there was a much more considerable amount of charcoal in this experiment 
than in any other. 
It need scarcely be stated that the very distinctive difference between the com¬ 
position of the solid and gaseous products of this powder are, generally, such as 
2 F 2 
