) proposes to use
hydrochloride of meta-phenylenediamine.]

~Exudation and Liquefaction Test for Blasting Gelatine, Gelatine Dynamite,
&c.~--A cylinder of blasting gelatine, &c., is to be cut from the
cartridge to be tested, the length of the cylinder to be equal to its
diameter, and the ends being cut flat. The cylinder is to be placed on end
on a flat surface without any wrapper, and secured by a pin passing
vertically through its centre. In this condition the cylinder is to be
exposed for 144 consecutive hours (six days and nights) to a temperature
ranging from 85 deg. to 90 deg. F. (inclusive), and during such exposure the
cylinder shall not diminish in height by more than one-fourth of its
original height, and the upper cut surface shall retain its flatness and
the sharpness of its edge.

~Exudation Test.~--There shall be no separation from the general mass of
the blasting gelatine or gelatine dynamite of a substance of less
consistency than the bulk of the remaining portion of the material under
any conditions of storage, transport, or use, or when the material is
subjected three times in succession to alternate freezing and thawing, or
when subjected to the liquefaction test before described.

~Picric Acid.~--The material shall contain not more than 0.3 part of
mineral or non-combustible matter in 100 parts by weight of the material
dried at 160 deg. F. It should not contain more than a minute trace of lead.
One hundred parts of the dry material shall not contain more than 0.3 part
of total (free and combined) sulphuric acid, of which not more than 0.1
part shall be free sulphuric acid. Its melting point should be between
248 deg. and 253 deg. F.

~Ammonite, Bellite, Roburite, and Explosives of similar Composition.~--
These are required to stand the same heat test as compressed
nitro-cellulose, gun-cotton, &c.

~Chlorate Mixtures.~--The material must not be too sensitive, and must
show no tendency to increase in sensitiveness in keeping. It must contain
nothing liable to reduce the chlorate. Chlorides calculated as potassium
chloride must not exceed 0.25 per cent. The material must contain no free
acid, or substance liable to produce free acid. Explosives of this class
containing nitro-compounds will be subject to the heat test.

~Page's Regulator.~--The most convenient gas regulator to use in
connection with the heat-test apparatus is the one invented by Prof.
F.J.M. Page, B.Sc.[A] (Fig. 49). It is not aff