pendulum, pressure gauge, and other testing apparatus, are here
subjected to chemical analysis in order to determine the component
materials and their exact percentages. Tests are also made to determine
the stability of the explosive, or its liability to decompose at various
temperatures, and other properties which are of importance in showing
the factors which will control the safety of the explosive during
transportation and storage.

In the investigation of all explosives, the first procedure is a
qualitative examination to determine what constituents are present.
Owing to the large number of organic and inorganic compounds which enter
into the composition of explosive mixtures, this examination must be
thorough. Several hundred chemical bodies have been used in explosives
at different times, and some of these materials can be separated from
others with which they are mixed only by the most careful and exact
methods of chemical analysis.

Following the qualitative examination, a method is selected for the
separation and weighing of each of the constituents previously found to
be present. These methods, of course, vary widely, according to the
particular materials to be separated, it being usually necessary to
devise a special method of analysis for each explosive, unless it is
found, by the qualitative analysis, to be similar to some ordinary
explosive, in which case the ordinary method of analysis of that
explosive can be carried out. Most safety powders require special
treatment, while most grades of dynamite and all ordinary forms of black
blasting powder are readily analyzed by the usual methods.

The examination of black blasting powder has been greatly facilitated
and, at the same time, made considerably more accurate, by means of a