Suns fixed and moveable.
21. Suns Fixed and Moveable.
Among the various amusing articles of pyrotechnic produce, none are more beautiful or afford greater remuneration of pleasure, than those under the denomination of Suns. They are of several kinds, as fixed, moveable, and transparent; they are all of simple construction.
Fixed suns after the following manner:—Provide a nave of wood, and in it fix fourteen or sixteen pieces in the form of radii; and to these radii attach jets of fire, the mouths of the jets being towards the circumference. A match must be applied in such a manner, that the fire communicated at the centre, may be conveyed at the same time, to the mouths of each of the jets; by which means each throwing its fire, the appearance will be that of a radiating sun; the wheel must be fixed in a vertical position.
The jets may be so arranged as to cross each other in an angular manner; in which case, instead of a sun you will have a star, or a sort of cross resembling that of Malta. Some of these suns are made also with several rows of jets; when they are so arranged they are called glories.
The wheel, or sun, may be caused to revolve by attaching jets to it in the direction of the circumference, with their heads and tails together. When the wheel is heavy four of the rockets must be fired together, and this in the following manner: supposing there are twenty cases employed, fire must be communicated at the same time to the first, the sixth, the eleventh, and the sixteenth; from which it will proceed to the second, the seventh, the twelfth, the seventeenth, and so on. These four rockets will make the wheel turn round with rapidity.
If two similar suns, with horizontal axes, are placed one behind the other, and made to turn in opposite directions, they will produce a very pleasing effect of cross-fire.
Three or four suns arranged on a similar axis, might be implanted in a vertical one, moveable in the middle of a table; which revolving around it would seem to pursue each other. They must be fixed firm on their axis and this axis must turn in the upright one in the middle of the table; and at the place where they rest on the table, should be furnished with a very moveable roller.
For a transparent sun, a prepared face of oiled paper, or Persian silk, painted in a proper manner, must be provided, and strained tight upon a hoop, which must be supported by pieces of strong wire, six or seven inches from the wheel, so that the light of it may illuminate the face. After the same manner may be represented in the front of a sun, the words Farewell, Vivat Rex, or Apollo, or any other figure may be painted on the silk.
Sometimes a small hexagonal wheel is fixed to the nave of the large wheel, whose cases must be filled with the same charge as the other; two of which must burn at a time, and begin with the others.
For a sun five feet in diameter, the cases should be those of eight ounces, filled with composition about ten inches. If the wheels are larger the cases must be proportionate to them.