Artificial fire-works

by Robert Jones

Having taught the method of ramming cases in moulds; we shall here say something concerning those filled without moulds, which method, for strong pasted cases, will do extremely well, and save the expence of making so many moulds. The reader must here observe, when he fills any sort of cases, to place the mould on a perpendicular block of wood, and not on any place that is hollow, for we have found by experience, that when cases were rammed on driving benches, which were formerly used, the works frequently miscarried, on account of the hollow resistance of the benches, which often jarred and loosened the charge in the cases; but this accident has never happened since the driving blocks[6] have been used.

When cases are to be filled without moulds, proceed thus; have some nipples made of brass or iron, of several sorts and sizes, in proportion to the cases, and to screw or six in the top of the driving block; when you have fixed in a nipple, make, at about one inch and a half from it, a square hole in the block, six inches deep and one inch diameter; then have a piece of wood, six inches longer than the case intended to be filled and two inches square; on one side of it cut a groove almost the length of the case, whose breadth and depth must be sufficient to cover near half the case; then cut the other end to fit the hole in the block, but take care to cut it so that the groove may be of a proper distance from the nipple: this half mould being made and fixed tight in the block, cut, in another piece of wood nearly of the same length as the case, a groove of the same dimensions as that in the fixed piece; then put the case on the nipple, and with a cord tie it and the two half moulds together, and your case will be ready for filling.

The dimensions of the above described half moulds, are proportionable for cases of eight ounces; but notice must be taken, that they differ in size in proportion to the cases.

Note, the clay, mentioned in this article, must be prepared after this manner; get some clay, in which there is no stones nor sand, and bake it in an oven till quite dry; then take it out and beat it to a powder, and afterwards sift it through a common hair sieve, and it will be fit for use.

Of the Proportion of Mallets.

The best wood for mallets is dry beech, though some have preferred other sorts of woods and have likewise pretended to determine their exact weight, which is not of much signification; however, for the better instruction of those who have not made a great progress in this art, I shall here give a good proportion for mallets; but at the same time would have every practitioner know, that if he makes use of a common mallet, of a moderate size, in proportion to the rocket, according to his judgment, and if that rocket succeeds, he may depend on the rest, by using the same mallet; yet it will be necessary that cases of different sorts be drove with mallets of different sizes.

The following proportion of the mallets for rockets of any size, from one ounce to six pound, may be observed; but as rockets are seldon made less than one ounce, or larger than six pound, I shall leave the management of them to the curious; but all cases under one ounce, may be rammed with an ounce rocket mallet. Your mallets will strike more solid, by having their handles turned out of the same piece as the head, and made in a cylindrical form: let their dimensions be worked by the diameters of the rockets: for example; let the thickness of the head be three diameters, and its length four, and the length of the handle five diameters, whose thickness must be in proportion to the hand.

Of the Proportion of Sky Rockets, with the Manner of heading them.

[Fig. 13.] represents a rocket compleat without its stick, whose length from the neck is five diameters one sixth; the cases should always be cut to this length, after they are filled: M the head, which is two diameters high, and one diameter one sixth and a half in breadth; N the cone or cap, whose perpendicular height must be one diameter one third. [Fig. 14.] is the collar to which the head is fixed; this is turned out of deal or any light wood, and its exterior diameter must be equal to the interior diameter of the head; one sixth will be sufficient for its thickness, and round the outside edge must be a groove; the interior diameter of the collar must not be quite so wide as the exterior diameter of the rocket; when this is to be glued on the rocket, you must cut two or three rounds of paper off the case, which will make a shoulder for it to rest upon. [Fig. 15], a former for the head; two or three rounds of paper well pasted will be enough for the head, which, when rolled, put the collar on that part of the former marked O, which must fit the inside of it; then with the pinching cord, pinch the bottom of the head into the groove, and tie it with small twine. [Fig. 16], represents a former for the cone. To make the caps, cut your paper in round pieces, equal in diameter to twice the length of the cone you intend to make; which pieces being cut into halves, will make two caps each, without wasting any paper; having formed the caps, paste over each of them a thin white paper, which must be a little longer than the cone, so as to project about half an inch below the bottom; this projection of paper, being notch’d and pasted, serves to fasten the cap to the head.