These formulæ, if somewhat incoherent, and clearly showing a want of experimental verification, indicate a real advance in pyrotechnic chemistry, not only by the addition of chlorate of potash, but by the multiplication of the number of metal salts used.
At the same time it is evident that the old alchemistic ideas were not entirely extinct by the use of such ingredients as ivory, mica, and pumice stone.
However, there can be no doubt that from the third decade of the nineteenth century dates the modern era of the pyrotechnic art. From this date onward chemical ingredients, metals and their salts as they were provided by the commercial chemist were eagerly taken and tested by the pyrotechnist, and adopted or rejected on their merits. And from this date begins the rapid elimination of useless additions.
Of those compositions given above the following salts are at present in use: nitrate of baryta, sulphide of antimony, sulphide of arsenic, nitrate of strontia, copper sulphate, carbonate of soda, and chlorate of potash.
Zinc, alum, lampblack, and oxide of iron are also used, but not for the purpose indicated.
Nitrate of copper and sulphate of soda would both be valuable ingredients, but their unstable nature prevents their use under modern conditions.
Meyer also describes the use of salts to tint an alcohol flame, which is merely an elaboration of Ruggieri’s palm tree and of little interest at the present time.
The next name prominent in pyrotechny is that of F. M. Chertier, who published in 1854 his “Nouvelles recherches sur les feux d’artifice,” after having published a pamphlet on the subject about twenty-five years previously.
In this work Chertier devotes most of his attention to the subject of colour, and although new ingredients have been introduced which were either unknown or were not then available on account of expense or other causes, since the time of his writing, yet there can be no doubt that Chertier stands alone in the literature of pyrotechny and as a pioneer of the modern development of the art.
Tessier, in the introduction to his “Treatise on Coloured Fires,” published in 1859, whilst paying tribute to Chertier’s work, regrets that he only possessed “quite superficial notions of chemistry.” Here speaks the chemist. The writer recently asked a pyrotechnic chemist of many years’ experience, whose knowledge of pyrotechnic chemistry is probably second to none, his opinion of Tessier’s book, and received this answer. “Tessier’s book contains too much chemical theory and too little pyrotechnic practice.” There speaks the pyrotechnist.