crucible on the water bath with an
alcoholic solution of sodium hydroxide, and where the nitro-glycerine is
decomposed, the liquid is evaporated to dryness. The residue is fused with
40 grms. of KOH and 5 grms. of potassium nitrate, the mass dissolved in
dilute acetic acid and filtered, and the sulphates precipitated in the
usual way. If camphor is present, it can be extracted with bisulphide of
carbon after the material has been treated with ether-alcohol. In that
case the sulphur, paraffin, and resin will also be dissolved. The camphor
being easily volatile, can be separated by evaporation. Let the weight of
the extract, freed from ether-alcohol before treatment with bisulphide of
carbon, equal A, and the weight of extract after treatment with CS_{2} and
evaporation of the same equal B; and weight of the residue which is left
after evaporation of the CS_{2} and the camphor in solution equal C, the
percentage of camphor will be A - B - C. The residue C may contain traces
of nitro-glycerine, resin, or sulphur.

Camphor may be separated from nitro-glycerine by means of CS_{2}. If the
solution of camphor in nitro-glycerine be shaken with CS_{2}, the camphor
and a little of the nitro-glycerine will dissolve. The bisulphide solution
is decanted, or poured into a separating funnel and separated from the
nitro-glycerine. The two solutions are then heated on the water bath to
20 deg. C. and then to 60 deg. C., and afterwards in a vacuum over CaCl_{2} until
the CS_{2} has evaporated from them. The camphor evaporates, and leaves
the small quantity of nitro-glycerine which had been dissolved with it.
The other portion is the nitro-glycerine, now free from CS_{2}. The two
are weighed and their weights added together, and equals the nitro-
glycerine present. There is a loss of nitro-glycerine, it being partly
evaporated along with the CS_{2}. Captain Hess has shown that it is equal
to about 1.25 per cent. This quantity should therefore be added to that
found by analysis. Morton Liebschutz, in a paper in the _Moniteur
Scientifique_ for January 1893, very rightly observes that the variety of
dynamites manufactured is very great, all of them having a special
composition which, good or bad, is sometimes of so complicated a nature
that the determination of their elements is difficult.

The determination of nitro-glycerine in simple dynamite No. 1 is easy; but
not so when the dynamite contains substances soluble in ether, such as
sulphur