This, we have remarked, is a combination of pieces, calculated, like the one we have described, to produce a variety of fires, variously arranged and distributed.
The pyric piece commonly commences with a turning sun. This sun consists of three cases, fixed to three arms proceeding from the centre. They are attached by means of a string, and have leaders which go from one to the other of the cases. See [Sun.] This sun communicates its fire to a fixed sun, formed of eight or nine strips of board, crossing each other, or as many spokes from a hub, to which are attached, lengthwise, as many cases, whose mouths are made to communicate fire by means of leaders; so that each case presents the appearance we have before described. Then follows a wheel consisting of two or more concentric circles, and round which are placed eight cases, with their mouths inclining a little upwards. These cases are generally charged with brilliant fire. They communicate with each other in the usual manner, and afterwards with a fixed star, placed on a stick, proceeding from the horizontal axis. This star is made of two cases, charged with Chinese fire, with their mouths upwards, and forming, with each other, an angle of forty-five degrees. This fire is then communicated to another wheel, and from that to one, on which, at certain distances, are fixed six smaller wheels, furnished with six cases each; so that the whole are put in motion at one time, the fire being communicated at the same period. The appearance of these smaller wheels, as the cases may be charged with the coloured fire-composition, is such as to exhibit the motion of a screw; which, however, depends on the structure of the wheel. The fire from this may then communicate to other wheels of the same kind, to cases of brilliant fire, to marrons and the like, differently arranged according to fancy. Cylinders of copper or tin, called barrels by some, are used in the arrangement, in the manner already described. In fact, the remarks we have before made on the regulated piece of nine mutations, the manner of forming as well as of executing it, will apply to the Pyric-piece.
Sec. XX. Of Sundry Illuminated Figures.
There are various illuminated pieces, some of which we purpose to notice in this section.
The illuminated pyramid, with Archimedean screws, a globe, and vertical sun, may be exhibited in the following manner: Let a pyramid be made twenty-one feet in height, and the height of the pedestal six feet, and breadth nine feet, having a space between the rails of six inches. They must be made as thin as possible, and in all put port-fires at intervals of four inches. The Archimedean screws are placed on the pedestal. They are nothing more than double spiral wheels, on which the cases are placed, but horizontally instead of obliquely. The vertical sun, placed four feet below the top of the pyramid, may consist of twelve rays. The globe on the top may be made in proportion to the pyramid. The leaders must be prepared and arranged in such a manner, that all the illuminating port-fires, or lances, screws, globe, and sun may take fire together.
Transparent stars with illuminated rays are formed, by making a strong circular block or body for the star, two feet in diameter, and attaching to it illuminated rays. In the centre of the front of the body, fix a spindle, on which put a double triangular wheel, six inches in diameter, clothed with two-ounce cases of brilliant charge. The cases on this wheel must burn only one at a time.
Round the edge of the body, nail a hoop made of thin wood or tin, which must project in front six or seven inches. In this hoop, cut three or four holes to let out the smoke from the wheel. The star may be cut out of strong pasteboard or tin in the following manner: Cut a round piece of pasteboard, two feet in diameter, on which draw a star, and cut it out. Over the vacancy, paste Persian silk, and paint the letters yellow; and also four of the rays yellow, and four red. This transparent star is to be fixed to the wooden hoop by a screw, to take off and on. The illuminated rays are made of thin wood, with tin sockets, fixed on their sides, within four inches of each other. In these rockets, put the illuminating port-fires, or lances; and behind the point of each ray, attach a half pound case of gray, black, or Chinese fire. The illuminated rays are to be lighted at the same time as the triangular wheel, or after it is burnt out. This may be done by a tin barrel, in the manner described in the regulated piece. Into this barrel, carry a leader from the illuminated rays, through the back of the star, which must be met by another leader, brought from the tail of the last case on the wheel.
The regulated illuminated spiral piece, with a projected star wheel, also illuminated, is made by procuring a block, eight inches in diameter, and putting in six iron spokes, which serve for spindles for the spiral wheels. These wheels are made one and a half feet in diameter, and three feet in height. The spindles must be of sufficient length to keep the wheels four or five inches from one another. At the end of each spindle, put a screw nut. On these spindles, the wheels, that hang downwards, are to run. On the spindles, which stand upwards, must be a shoulder, for the blocks of the wheels to run on. The projected star wheel turns on the same spindle on which the large block is fixed. This spindle must be long enough to admit the star-wheel to project a little before the spiral wheels. The exterior diameter of the star wheel is five feet five inches. On this wheel, three circles of iron wire are to be fixed, to which attach either port, or other illuminating fires. On the block, place a transparent star, or a large five-pointed brilliant star. The cases on this wheel may burn four at once. The cases on the spiral wheels must be placed parallel to their fells and burn two at a time.
In order to make a figure-piece, with five-pointed stars, illuminated, all that is necessary is to have a vertical wheel about one foot in diameter, and furnished with six four-ounce cases of different coloured charge, which must burn double. On the frame of the figure piece, fix five-pointed brilliant or blue stars, rammed four inches with composition. Let the space between each star be eight inches, and, at each point, fix a gerbe or case of Chinese fire. The gerbe, stars, and wheel are to be lighted at the same time.
The illuminated star wheel may be formed by procuring a fell about four feet in diameter, and placing, within this fell, three circles of iron wire, one smaller than the other, so that the diameter of the least may be about ten inches. Place the port, or other fires on these fells, with their mouths inclining outwards, and the port-fires on the points of the star, with their mouths projecting in front. The exterior fell must be clothed with four-ounce cases of gray charge. They must burn four at a time and be lighted at the same time with the illuminations.