Page:Pyrotechnics the history and art of firework making (1922).djvu/179

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A curious firework, now almost obsolete, for which it is difficult to find a class, is the five-pointed star. This work consisted of a case having a diaphragm of plaster of paris or clay above the filling, below which five holes are bored equidistant and at right angles to the axis. The case is fired in the unusual position of horizontal with the end towards the spectator, the fire playing all round the case, forming a star. The composition used was mealed powder, sulphur, saltpetre, and sulphuret of antimony. Ruggieri mentions this firework under the name "Etoile fixé," and it is mentioned by Jones, writing in 1765, but not by Frézier.

It is hard to believe that this unit was successful, so many factors militating against success, which depends upon the exactly similar jet from each of the five holes. But it is possible that in large geometrical pieces it was at least of use to give an additional effect in what, owing to the lack of variety of the fireworks of the time, must have been rather a monotonous repetition of a few effects. It also would enable small blank spaces to be filled in on set pieces. In a sun or star of the ordinary type, that is of radiating cases, the commencement of the jets must be as far apart as the length of two of the cases, which length is governed by the required time of burning. This leaves a blank centre; the five-pointed star, however, if working correctly, has the jets radiating from a point.

Many of the earlier writers classified fireworks under the heads:—Fireworks for the ground, for the air, and for the water. Those falling in the latter division are only variations of those for the ground, that is to say, a gerb, fountain or other firework is fitted with a float, such as a block of wood, and functions floating on the surface of the water, the effect being greatly enhanced by the reflection.

It is not proposed to deal separately in this work with