The products of perfectly detonated gun-cotton may be expressed by the
following equation:--

2C_{12}H_{14}O_{4}(NO_{3})_{6} = 18CO + 6CO_{2} + 14H_{2}O + 12N.

It does not therefore contain sufficient oxygen for the complete
combustion of its carbon. It is for this reason that when used for mining
purposes a nitrate is generally added to supply this defect (as, for
instance, in tonite). It tends also to prevent the evolution of the
poisonous gas, carbonic oxide. The success of the various gelatine
explosives is due to this fact, viz., that the nitro-glycerine has an
excess of oxygen, and the nitro-cotton too little, and thus the two
explosives help one another.

In practice the gases resulting from the explosion of gun-cotton are--
Carbonic oxide, 28.55; carbonic acid, 19.11; marsh gas (CH_{4}), 11.17;
nitric oxide, 8.83; nitrogen, 8.56; water vapour, 21.93 per cent. The late
Mr E.O. Brown, of Woolwich Arsenal, discovered that perfectly wet and
uninflammable compressed gun-cotton could be easily detonated by the
detonation of a priming charge of the dry material in contact with it.
This rendered the use of gun-cotton very much safer for use as a military
or mining explosive.

As a mining explosive, however, gun-cotton is now chiefly used under the
form of tonite, which is a mixture of half gun-cotton and half barium
nitrate. This material is sometimes spoken of as "nitrated gun-cotton."
The weight of gun-cotton required to produce an equal effect either in
heavy ordnance or in small arms is to the weight of gunpowder in the
proportion of 1 to 3, i.e., an equal weight of gun-cotton would produce