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

by G. W. Mortimer

By attaching a second set of cases, so arranged as to take fire when the first set are consumed, the wheel (running upon level ground) will return to the same place from which it received its primary impulse.

This kind of wheels, when constructed with care, affords a very pleasing recreation. It may be readily seen, that many other ornamental pieces of less magnitude may be attached to the same axle:—a good level school ground is favourable for the exhibition of this article.

Horizontal changed to a Vertical Wheel.

14. Horizontal changed to a Vertical Wheel.

The Wheel for this should be about three feet six inches diameter. On its circumference fix sixteen half-pound cases filled with brilliant charge, two of which should burn at a time. On each end of the nave, must be a tube or barrel of tin or brass, in diameter something less than that of the nave, and in height about six inches; this is the construction of the wheel. The stand to which it is to be fixed is as follows: set a post of any kind of wood, about four inches square, firmly into the ground, standing up about five feet; then from the top saw off about two feet, which piece must be joined again at the place where it was cut, with a strong hinge on one side, in such a manner that it may lift up and down in front of the stand; on the top of the bottom part, the side on which the moveable part falls, fix a very strong bracket projecting about a foot from the post; and at the extremity of which form a tenon, corresponding to a mortice made in the moveable part, so that when it falls it may be firmly fixed to it; this particular must be attended to, or the force with which the wheel revolves when vertical, will be liable to pull off the hinge. On the side of the short post opposite the hinge, nail a piece of wood, extending about eighteen inches down the bottom part of the post, to which it must be tied with a piece of string only, which will be sufficient to keep the short part perpendicular; in the top of the latter, fix a spindle, ten or twelve inches long; on this spindle put the wheel; then fix on a brilliant sun with a single glory, the diameter of which must be about six inches less than that of the wheel. The wheel being ready to fire, light the wheel part first, and let it run horizontally till four cases are consumed, then from the end of the fourth case carry a leader into the tin barrel that turns over the end of the stand; this leader must be met by another brought through the top of the post, from a case filled with a strong port-fire charge, and tied to the bottom post, with its mouth directed towards the string which holds up the upper part of the post, so that when this case is lighted, it will burn the string and let the wheel fall downward, by which means it will become vertical; then from the last case of the wheel carry a leader into the barrel next the sun, which will exhibit its beauties immediately the wheel has ceased.

The sudden change of this piece renders it very surprising and pleasing to the observers of it, and entitles it to great attention.

Vertical Scroll Wheel.

15. Vertical Scroll Wheel.