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MINUTES OF PROCEEDINGS OF 
the pressure. The result was a compound of pressure and vibration. The crusher 
moved backwards and forwards in its casing from the effect of the vibration of the 
walls of the gun. The crusher would thus to some extent act as a hammer. 
Professor Abel, the Chemist of the War Department, said so many points had 
been raised in the very interesting lecture they had heard, that he scarcely knew 
which to speak of first. Everyone present must be struck with the remarkable 
progress which had been made in the investigation of this subject within a very 
recent period ; but, although very much information had been gained, he hoped and 
believed that further researches would elicit still more valuable results. Captain 
Morgan had laid before them many interesting facts and ideas on the subject which 
could not be controverted, but on several points which he had touched upon opinions 
varied. With regard, for instance, to the unexploded powder which is sometimes 
thrown out of the gun, he (Mr. Abel) believed that beyond doubt the particles 1) ad 
been in a state of ignition, and, indeed, were burning at the instant of their projec¬ 
tion from the gun, but that the sudden expansion of gas had the effect of 
extinguishing them. The condition of the surfaces of these particles indicated that 
the most inflammable portions of the masses had been burning, and the fragments 
of pellet powder especially afforded convincing evidence of having been burning 
and of its extinguishment being accidental. He thought they could not avoid the 
conclusion that during the explosion of a charge each particle of powder remained 
isolated from the others, through the agency of the gases evolved from their surfaces. 
The theory adopted by the lecturer that the particles composing the two extremities 
of a charge became jammed up in a solid mass, did not therefore appear to him (Mr. 
Abel) to be one which he could accept; in fact, experiment appeared, as far as it had 
been carried, to demonstrate the opposite. He would not enter into a controversy 
concerning the precise effects to be ascribed to the density of gunpowder, simply 
remarking that there were abundant proofs that the properties of gunpowder might 
to a considerable extent be regulated by variation of density. There was another 
variable property of gunpowder which had perhaps not attracted the attention it 
deserved—perhaps because it was so difficult of comparison in different powders— 
and that was the property of hardness. Some powders were very hard though their 
density was low; and as hardness, apart* from density, no doubt exercised an 
important influence on the rate of burning of a powder, it was highly desirable, if 
possible, that reliable means should be devised for registering this quality. The 
production of a powder thoroughly suitable for the large guns of the present day 
was unquestionably a difficult problem. There was no doubt that theoretically they 
ought to have a distinct powder for each kind of gun; but that being obviously 
impracticable, they must endeavour so to regulate and balance the various properties 
of the powder as to obtain, with as little sacrifice of power as possible in the smaller 
of the guns, a powder which can be safely used in the heaviest charges. His name 
had been mentioned by the lecturer as objecting to deductions founded on the experi¬ 
ments of Bunsen and Schischkoff; he would therefore wish to state that his objections 
■were specially directed against the mode of operation pursued in their investigations. 
He considered the method of experimenting to be fallacious, firstly, because they 
did not explode gunpowder under pressure, when collecting the products; and 
secondly, because some of the products were submitted to treatment which must 
involve secondary changes before they were examined, and hence one might expect 
to obtain analytical results which would not fairly represent the original products of 
explosion. The experiments which were now being made in reference to the 
character of the decomposition of gunpowder by Captain A. Noble, were likely to 
furnish very important results. Captain Noble, in conducting his investigations, 
was exploding charges of considerable amount in strong vessels either absolutely or 
nearly closed, and was thereby likely to arrive at results approximating much more 
closely to those of actual practice than any which hitherto had been obtained. The 
physical and chemical results attending the explosion of gunpowder constituted a 
