The Chemistry of Powder and Explosives - Sciencemadness Dot Org

62 PYROTECHNICS
The chlorate compositions recommended by Ruggieri would
undoubtedly give good colors, but are not altogether safe and
would probably explode if pounded into their cases. They could
be loaded with safety in an hydraulic press, and would probably
not explode if tamped carefully by hand.
F. M. Chertier, whose book "Nouvelles recherches sur les feux
d'artifice" was published at Paris in 1854, devotes most of his
attention to the subject of color, so successfully that, although
new materials have come into use since his time, Brock says that
"there can be no doubt that Chertier stands alone in the literature
of pyrotechny and as a pioneer in the modern development
of the art." 17 Tessier, in his "Chimie pyrotechnique ou traite
pratique des feux colores," first edition, Paris, 1859, second edition
1883, discusses the effect of individual chemicals upon the
colors of flames and gives excellent formulas for chlorate and for
non-chlorate compositions which correspond closely to present
practice. He used sulfur in many but not in all of his chlorate
mixtures. Pyrotechnists in France, with whom the present writer
talked during the first World War, considered Tessier's book at
that time to be the best existing work on the subject of colored
fires—and this in spite of the fact that its author knew nothing
of the use of magnesium and aluminum. The spectroscopic study
of the colors produced by pure chemicals, and of the colors of
pyrotechnic devices which are best suited for particular effects, is
the latest of current developments.
Chlorate mixtures which contain sulfur give brighter flames
than those which lack it, and such mixtures are still used occasionally
in spite of their dangerous properties. The present tendency,
however, is toward chlorate mixtures which contain no
sulfur, or toward potassium nitrate mixtures (for stars, etc.)
which contain sulfur but no chlorate, or toward nitrates, such as
those of strontium and barium, which supply both color for the
flame and oxygen for the combustion and are used with magnesium
or aluminum to impart brilliancy. Magnesium was first
used for pyrotechnic purposes about 1865 and aluminum about
1894, both of them for the production of dazzling white light.
These metals were used in the compositions of colored airplane
17 Brock, op. cit., p. 147. Chertier also published a pamphlet on colored
fires nearly thirty years earlier than the above-mentioned book.