A form of firework device is called the pyrotechnic machine (machine pyrique). This ends ordinarily with a star. It is formed from six bars having a length of from three to four feet. These are screwed on a hub equal to that of a fixed sun. Two jets are attached on a traverse. Their throats cross, and the opening of the angle given them is the measure for the formation of a star. A match laid in a groove on each one of the bars communicates from one end with the throat of the jets and from the other with a circular match, which surrounds the hub in the foot of the bars, and thus communicates the fire to all at the same time. In place of the jets forming the star, the bars may be garnished with six turning suns. (Pl. X, figs. 1, 2, 7, 8, 9,19, and 20.)
It is with such suns that decorations are formed for those displays set within frames and the trellis effect in flaming arbors. They are usually constructed with three jets which take fire successively.