FIREWORKS

products of the art of pyrotechny (t.e.), the making of scenic effects by fire and chemical compound s, Pyrotechny is of very ancient origin, f’s of a kind being known in China for many ages, while displays were given in Rom. circuses from an early date. Gunpowder, however, practically revolutio nized the art and researches of chemists, and scientists have rendered the making of modern f’s a fine art. The burning of certain minerals, mixed in definite proportions, gives different colored effects, and upon this fact the variations in f’s may be said to lie. The minerals generally used, and the color effects they produce are as follows: barium—green; calcium— red; copper—green or blue; lithium carbonate—purple-red; salts of stronphide of antimony—white; sulphide of arsenic—white. Charcoal and sulphur are greatly used, too, and mixed with a proportion of nitre form gunpowder. After the compounds have been mixed they are packed in cylindrical cases, generally made of pasteboard, and the cases are made with mathematical precision, for much depends on their size and shape. Amongst simple f’s are crackers, squibs, Roman candles, stars, sparks, maroons, Bengal lights, jack-in-the boxes, colored fire, etc., whilst the more complicated are rockets, bombs, rotating or Catherine wheels, and set pieces (battles or portraits.)