Third Mutation.—This is moveable, and is only an octagon vertical wheel, clothed with four-ounce cases, filled with brilliant charge. Two of these cases must burn at a time. In this wheel, we may make changes of fire.
Fourth Mutation.—This is a fixed sun of brilliant fire, consisting of twelve four-ounce cases. The necks of these cases must be a little larger than those of four-ounce wheel cases. In this mutation, may be made a change of fire, by filling the cases half with brilliant charge, and half with gray.
Fifth Mutation.—This is a fixed piece called the porcupine quills. This piece consists of twelve spokes, standing perpendicular to the block in which they are fixed. On each of these spokes, near the end, must be placed a four-ounce case of brilliant fire. All these cases must incline either to the right or left, so that they may all play one way.
Sixth Mutation.—This is a standing piece called the cross fire. This mutation consists of eight spokes fixed in a block. Near the end of each of the spokes, must be tied two four-ounce cases of white charge, one across the other; so that the fires from the cases on one spoke may intersect the fire from the cases on the other.
Seventh Mutation.—This is a fixed wheel with two circular fells, on which are placed sixteen eight-ounce cases of brilliant fire, in the form of a star. This piece is called a fixed star of wild fire.
Eighth Mutation.—This is a beautiful piece, called a brilliant star piece. It consists of six spokes, which are strengthened by two fells of a hexagon form, at some distance from each other. At the end of each spoke, in the front, is fixed a brilliant star of five points; and on each side of every star is placed a four-ounce case of black or gray charge. These cases must be placed with their mouths sidewise, so that their fires may cross each other.
Ninth Mutation.—This is a wheel piece. It is composed of six long spokes, with a hexagon vertical wheel at the end of each. These wheels run on spindles in front of the spokes. All the wheels are lighted together. Two-ounce cases will be sufficient for these wheels, and may be filled with any coloured charge.
II. With respect to the proportion of these mutations, with the method of conveying the fire from one to the other, and the distance they stand from each other on the spindle, the following general remarks will be sufficient.
The first mutation must be a hexagon vertical wheel fourteen inches in diameter. On one side of the block, whose diameter is two and one-fourth inches, is fixed a tin barrel. This barrel must be a little less in diameter than the nave. Let the length of the barrel, and block be six inches. Having fixed the cases on the wheel, carry a leader, from the tail of the last case, into the tin barrel, through a hole, made on purpose, two inches from the block. At the end of this leader, let there be about one inch, or two, of loose match; but be careful to secure the hole, in which the pipe is put, to prevent any sparks falling in, which would light the second mutation before its time, and confuse the whole.