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MINUTES OE PEOCEEDINGS OE 
The “force brisante ” of Gun Cotton . 
[The points discussed under this head, and which involve the question of the applicability of gun 
cotton to artillery, as a substitute for gunpowder, require a careful, systematic experimental 
examination]. 
16. This subject, purely artilleristic in its nature, can only be spoken 
of by chemists so far as the force brisante of gun cotton depends upon a 
certain chemical condition. 
By the expression force brisante we understand the time within which 
a certain weight of an explosive material in a gun has been converted into a 
certain volume of gas or the volume of gas produced under otherwise equal 
conditions. 
An explosive material is therefore the more brisante in proportion as the 
time is short for equal weight and volume of gas developed, or time and 
weight equal in proportion to the volume of gas is greater. 
We, being accustomed to compare every sort of explosive material with 
gunpowder, say that gun cotton is more brisante than gunpowder, because 
the former developes an equal volume of gas in a smaller space of time—or, 
what is the same, time being equal, a greater bulk of gas, and, therefore, a 
higher mechanical effect. In the moment of explosion the result exerts a 
greater pressure on the barrel; hence there is more danger of bursting. 
The danger of bursting by equal charges differs relatively according to the 
thickness of the barrel and the strength of its material to equal resistance 
of the shot. 
Given an explosive substance more brisante than gunpowder, we can 
still fire the two with equal safety by proportionately increasing the strength 
of the gun. Brom a consideration of explosive bodies generally, it follows 
that each particular one, if applied to ballistic purposes, demands a peculiar 
gun. It cannot be reasonably expected that a gun best adapted to the use 
of gunpowder is also best adapted to the use of gun cotton. 
If that construction be discovered, then the higher brisante effect of 
gun cotton may appear as an advantage, instead of being thought a 
disadvantage. 
However, gun cotton can act disadvantageous^ in another manner on 
the barrel of a gun, through its higher brisante nature. 
If we imagine the moment of the discharge of the gun taking place, then 
the products of the explosion—the gases, are as it were, in a mine, in 
which one of the resisting sides is movable, viz. the shot. The gases act 
with equal mechanical power on every side of the barrel in the moment 
before the shot is about to move. The sides of the gun being at rest 
(supposing it resists the explosion), it follows that part of the mechanical 
power is transformed in an equivalent quantity of heat, or, what is the same, 
the barrel of the gun will become heated; the temperature may be raised 
thereby so high, that the tin of a bronze barrel may partly melt, or, as we 
say, the barrel of the gun is “burnt out” after a number of rounds. 
That the last-named effect of heat on the barrel is not to be attributed to 
the chemical composition of gun cotton, but to the transformation of 
mechanical power into heat, is proved by Lieutenant von Karolyi's analysis 
of the gases of combustion of LenFs gun cotton, which he made in the 
