Endless Amusement / A Collection of Nearly 400 Entertaining Experiments in Various Branches of Science; Including Acoustics, Electricity, Magnetism, Arithmetic, Hydraulics, Mechanics, Chemistry, Hydrostatics, Optics; Wonders of the Air-Pump; All the Popular Tricks and Changes of the Cards, &c., &c. to Which is Added, a Complete System of Pyrotechny; Or, the Art of Making Fire-works.

by Unknown

Of the Method of mixing Compositions.

The performance of the principal part of fire-works depends much on the compositions being well mixed; therefore, great care ought to be taken in this part of the work, particularly in the composition for sky-rockets. When you have four or five pounds of ingredients to mix, which is a sufficient quantity at a time, (for a larger proportion will not do so well,) first put the different ingredients together, then work them about with your hands, till you think they are pretty well incorporated: after which, put them into a lawn sieve with a receiver and top to it; and if, after it is sifted, any should remain that will not pass through the sieve, grind it again till fine enough; and if it be twice sifted it will not be amiss; but the compositions for wheels and common works are not so material, nor need be so fine. But in all fixed works, from which the fire is to play regular, the ingredients must be very fine, and great care taken in mixing them well together: and observe, that, in all compositions wherein are steel or iron filings, the hands must not touch; nor will any works which have iron or steel in their charge, keep long in damp weather, without being properly prepared, according to the following directions:—

It may sometimes happen, that fire-works may be required to be kept a long time, or sent abroad; neither of which could be done with brilliant fires, if made with filings unprepared; for this reason, that the saltpetre being of a damp nature, it causes the iron to rust, the natural consequence of which is, that when the works are fired, there will appear but very few brilliant sparks, but instead of them a number of red and drossy sparks; and besides, the charge will be so much weakened, that if this should happen to wheels, the fire will not be strong enough to force them round; to prevent such accidents, prepare your filings after the following manner:—Melt in a glazed earthen pan some brimstone over a slow fire, and when melted, throw in some filings, which keep stirring about till they are covered with brimstone; this you must do while it is on the fire; then take it off, and stir it very quick till cold, when you must roll it on a board with a wooden roller, till you have broken it as fine as corn powder; after which, sift from it as much of the brimstone as you can. There is another method of preparing filings, so as to keep two or three months in winter; this may be done by rubbing them between the strongest sort of brown paper, which has been previously moistened with linseed oil.

N.B. If the brimstone should take fire, you may put it out, by covering the pan close at top. It is not of much consequence what quantity of brimstone you use, provided there is enough to give each grain of iron a coat; but as much as will cover the bottom of a pan of about one foot diameter, will do for five or six pounds of filings. Cast-iron for gerbes will be preserved by the above method.

To make Crackers.

Cut some stout cartridge-paper into pieces three inches and a half broad, and one foot long; one edge of each of these pieces fold down lengthwise about three-quarters of an inch broad; then fold the double edge down a quarter of an inch, and turn the single edge back half over the double fold; open it, and lay all along the channel, which is formed by the foldings of the paper, some meal-powder; then fold it over and over till all the paper is doubled up, rubbing it down every turn; this being done, bend it backwards and forwards, two inches and a half or thereabouts, at a time, as often as the paper will allow; hold all these folds flat and close, and with a small pinching cord, give one turn round the middle of the cracker, and pinch it close; bind it with packthread, as tight as you can; then in the place where it was pinched, prime one end, and cap it with touch-paper. When these crackers are fired, they will give a report at every turn of the paper; if you would have a great number of bounces, you must cut the paper longer, or join them after they are made; but if they are made very long before they are pinched, you must have a piece of wood with a groove in it, deep enough to let in half the cracker; this will hold it straight while it is pinching.

To make Squibs and Serpents.

First make the cases, of about six inches in length, by rolling slips of stout cartridge-paper three times round a roller, and pasting the last fold; tying it near the bottom as tight as possible, and making it air-tight at the end, by sealing-wax. Then take of gunpowder half a pound, charcoal one ounce, brimstone one ounce, and steel-filings half an ounce, (or in like proportion,) grind them with a muller, or pound them in a mortar. Your cases being dry and ready, first put a thimble-full of your powder, and ram it hard down with a ruler; then fill the case to the top with the aforesaid mixture, ramming it hard down in the course of filling, two or three times; when this is done point with touch-paper, which should be pasted on that part which touches the case, otherwise it is liable to drop off.

Sky-Rockets.

Rockets being of the fire-works most in use, we shall give them the preference in description. As the performance of rockets depends much upon their moulds, they should be made according to the following proportions:—Taking the diameter of the orifice, its height should be equal to six diameters and two-thirds: the choke, one diameter and one-third of this model, will serve for every rocket from 4 oz. to 6 lb.—For instance:—suppose the diameter of a rocket of 1 lb. be 1½ inch, then its length being 6 diameters and two-thirds, the length of the case must be 10⅓ inches, and the choke 2¼ inches. Your rammer must have a collar of brass, to prevent the wood from splitting.