COLORED LIRE. In producing light and color, there is added to the gunpowder composition steel filings for brilliant fire or east-iron filings for Chinese fire. Copper filings give a greenish tint to flame; zinc filings a fine blue color: powdered magnesium a dazzling white light: amber. colo phony, or common salt affords yellow fire. Lamp .black produces a very red color with gunpowder, and a pink with nitre in excess, and it serves for making golden showers. Yellow sand or glisten ing mica communicates to fireworks golden radia tions. Verdigris imparts a pale green: sulphate of copper and sal ammoniac a palm-tree green; barium salts a grass green ; strontium salts crimson; calcium salts orange. Potassium pie rate on burning produces a whistling sound and has recently been introduced for use in whistling bombs and rockets. Camphor yields a very white flame and aromatic fumes. Lycopodium burns with a rose color and a magnificent flame. The published recipes and formulas for the manu facture of the materials used in fireworks are very numerous, while each manufacturer has his special mixtures and methods of treatment. For example. yellow stars and !fellow showers are made of nitre 16 parts, sulphur 10, charcoal 4, gunpowder 16, and lampblack 2. all being finely ground and intimately mixed. A deeper and richer golden color is produced by using 2 parts less of sulphur and of charcoal respectively and 4 parts more of gunpowder in the mixture. To produce stars either of the above mixtures is moistened with glint water, rolled into a sheet and cut into cubes which are then dried. For red mixture for colored fires potassium chlorate 20.7 parts, sulphur 17.2, charcoal 1.7, strontium nitrate 45.7, black antimony sulphide 5.7. For yrc n, potassium chlorate 32.7 parts, sulphur 9.S, charcoal 5.2, barium nitrate 52.3. Fur blue, potassium chlorate 34.5 parts, charcoal 1S.1, ammoniac•al copper sulphate 27.4. For irkite, sulphur 20 parts, saltpetre 60, black antimony sulphide 5, flour gunpowder 15.
All fireworks mixtures and compositions should be handled with extreme care. All friction should be avoided, especially while the ingredients are being mixed. Compositions containing chlorates.
and particularly chlorates and sulphur, are es pecially sensitive to friction and percussion, and furthermore are liable to explode spontaneously. The sensitiveness of such mixtures may be noted in the toy torpedo o• throw-down, in which a very small amount of the mixture, mingled with gravel to give the device weight, are enveloped in tissue paper. Owing to frequent accidents to person and property. through explosions and fire, arising from the use of firecrackers, and espe cially the larger sizes known as cannon crackers, giant crackers, and dynamite crackers, a straw board cracker containing a chamber tilled with compressed air has recently been invented as a substitute. Greek fire (q.v.) is supposed by some to have been composed of asphaltum, nitre, and sulphur, by others to have had approxi mately the composition of gunpowder. A modern composition known by this name consists of a solution of phosphorus in carbon disulphide with or without sulphur, potassium chlorate, and mineral oil. Rockets. known as Congo re rockets, carrying explosive shells and incendiary composi tions in the pot, were used in the siege of Bou logne in 1806 and in the British war with the Burmese. Bengal lights are used as distress sig nals at sea, while Boman candles, or similar de vices throwing colored stars. are used. with a telegraphic code. for over-water communication. In 1900 there were produced in the United States $1,785,271 worth of fireworks, nearly one-half of the total amount being produced in the State of New York: IrLIOCIIAPIIY. The literature of pyrotechny contains the following works. whose scope is in dicated by their titles: Babiugton, Pyroteehnia, or a Discourse of Artificial Fireworks (London, 1635) ; d'Orval. Trait(' dc,ss fear d'artifiec pour le spectacle et pour In guerre (Bern. 1750) ; Rug gieri, Pyrotechnic militairc (Paris, 1S)2); Cut bush. A Syst( in of Pyrotechny (Philadelphia. Chertier. sue Ics fcux d'artifice I Paris, : Tessier, (Mimic pyrotrchnique (Paris. 18501 : Browne., The .111 of Pyrotichny (London, )S791: Cesare Sonzogno. 17 piroteenico 'materna (Srilan, IS92), Ex