A Manual of Pyrotechny; or, A Familiar System of Recreative Fire-works

by G. W. Mortimer

Plural Wheels.

9. Plural Wheels.

So called from there being several of them fixed on the same axis; they are generally horizontal, and in number three. The diameter of the middle wheel may be a little less than the other two.

The cases must be fixed to the ends of the spokes in notches cut on purpose, or there may be half cylinders of tin nailed to the ends of the spokes, and the cases tied in them. The bottom cases should play obliquely upwards; the middle set horizontally; and the upper cases obliquely downwards. The leaders must be arranged so that the cases may burn first up, then down, then horizontal, through the whole sets. By driving in the end of the last case two or three ladles full of slow-fire, it will cause it to burn till the wheel has stopped its course; and if the other cases are fixed in the contrary way, the wheel will then revolve in a contrary direction, and have a pleasing appearance. For the case at top of the axis, a gerbe may be well employed; the case on the spokes should be filled with a strong brilliant charge.