Part 8

This, however, would not be the case, unless the Rocket was pierced to a certain depth. A sufficient quantity of elastic fluid would not be produced; for the composition would inflame only in circular coats, of a diameter equal to that of the Rocket; and experience shows that this is not sufficient. Recourse then is had to the very ingenious idea of piercing the Rocket in a conical hole, which makes the composition burn in conical strata, which have much greater surface, and produce a much greater quantity of inflamed matter and fluid. This expedient was certainly not the work of a moment.

The stick serves to keep it perpendicular; for if the Rocket should begin to tumble, moving round a point in the choak, as being the common centre of gravity of Rocket and stick, there would be so much friction against the air by the stick, between the centre and the point, and the point would beat against the air with so much velocity, that the reaction of the medium would restore it to its perpendicularity. When the composition is burnt out, and the impulse upwards has ceased, the common centre of gravity is brought lower towards the middle of the stick, by which means the velocity of the point of the stick is decreased, and that at the point of the Rocket is increased; so that the whole will fall down, with the Rocket end foremost.

During the time the Rocket burns, the common centre of gravity is shifting and getting downwards, and still faster and lower as the stick is lighter; so that it sometimes begins to tumble before it is quite burnt out: but when the stick is too heavy, the common centre of gravity will not get so low, but that of the Rocket will rise straight, though not so fast.

From the experiments of Mr. Robins, and other Gentlemen, it was found that the Rockets of two, three, or four inches diameter, rise the highest; and they are found to rise to all heights in the air, from 400 to 1,254 yards, which is about three-quarters of a mile. For further particulars respecting the theory of the flight of Rockets our readers are referred to Robins’s Tracts, vol. 2.--Philosophical Transactions, vol. 46, page 578: and more particularly to Mr. W. Moor’s “Treatise on the motion of Rockets,” in which they will find the subject elegantly treated.

SECTION VII.

TABLES OF VARIOUS COMPOSITIONS.

1. SERPENTS.--Mealed-powder one pound, salt-petre one ounce and three-quarters, charcoal one ounce.

2. PIN WHEELS.--Mealed-powder twelve ounces, salt-petre three ounces, sulphur one ounce and a-half, steel-filings two ounces.

3. COMMON STARS.--Salt-petre one pound, sulphur four and a-half ounces, antimony four ounces, isinglass half an ounce, camphor half an ounce, spirits of wine three-quarters of an ounce.

4. WHITE STARS.--Mealed-powder four ounces, salt-petre twelve ounces, sulphur six ounces and a-half, oil of spike two ounces, camphor five ounces.

5. BLUE STARS.--Mealed-powder eight ounces, salt-petre four ounces, sulphur two and a-half ounces, isinglass two ounces, spirits of wine two ounces.

6. TAILED STARS.--Mealed-powder three ounces, salt-petre one ounce, sulphur three ounces, charcoal one ounce.

7. DROVE STARS.--Salt-petre one pound, sulphur eight ounces, antimony four ounces.

8. POINTED STARS.--Salt-petre eight and a-half ounces, sulphur two ounces, antimony one ounce and three-quarters.

9. STARS OF A FINE COLOUR.--Mealed-powder one ounce, salt-petre one ounce, sulphur one ounce, oil of turpentine four drams, camphor four drams.

10. VARIEGATED STARS.--Mealed-powder eight drams, roch-petre four ounces, vivum two ounces, camphor two ounces.

11. BRILLIANT STARS.--Mealed-powder three-quarters of an ounce, salt-petre three ounces and a-half, sulphur one and a-half ounce, spirits of wine one ounce and a quarter.

12. TAILED STARS.--Salt-petre four ounces, sulphur six ounces, antimony two ounces, rosin four ounces.

13. DITTO WITH SPARKS.--Mealed-powder one ounce, salt-petre one ounce, camphor two ounces.

14. GERBES.

1. Mealed-powder one pound and a-half, coarse iron-sand five ounces.

2. Mealed-powder two pounds, coarse iron-sand eight ounces, salt-petre one pound.

15. ROMAN CANDLES.--Mealed-powder half-a pound, salt-petre two pounds and a-half, sulphur half-a pound, glass-dust half-a pound.

16. TOURBILLONS.

_For four ounce cases._--Mealed-powder one pound two ounces, charcoal two ounces and a-quarter.

_For eight ounce cases._--Mealed-powder two pounds, charcoal four ounces three-quarters.

17. SHOWERS OF FIRE.

_Chinese._--Mealed-powder one pound, sulphur two ounces, iron-sand first order five ounces.

_Ancient._--Mealed-powder one pound, charcoal two ounces.

_Brilliant._--Mealed-powder one pound, iron-sand first order four ounces.

18. GOLDEN RAIN.

1. Mealed-powder four ounces, salt-petre one pound, sulphur four ounces, brass-dust one ounce, saw-dust two ounces and a-quarter, glass-dust six drams.

2. Mealed-powder twelve ounces, salt-petre two ounces, charcoal four ounces.

3. Salt-petre eight ounces, sulphur two ounces, brass-dust a quarter of an ounce, antimony three-quarters of an ounce, saw-dust twelve drams, glass-dust one ounce.

19. SILVER RAIN.

1. Mealed-powder two ounces, salt-petre four ounces, sulphur two ounces, antimony two ounces, sal-prunella half an ounce.

2. Salt-petre half an ounce, sulphur two ounces, charcoal four ounces.

3. Mealed-powder two ounces, salt-petre four ounces, sulphur one ounce, steel-dust three-quarters of an ounce.

20. WATER ROCKETS.

1. Mealed-powder three pounds, salt-petre two pounds, sulphur one pound and a-half, charcoal two pounds and a-half.

2. Salt-petre one pound, sulphur four pounds and a-half, charcoal six pounds.

3. Salt-petre one pound, sulphur four ounces, charcoal twelve ounces.

4. Mealed-powder four ounces, salt-petre one pound, sulphur eight ounces and a-half, charcoal two ounces.

21. SINKING CHARGE FOR DITTO.

Mealed-powder ten ounces, charcoal one ounce.

22. WATER SERPENTS.

1. Mealed-powder one pound, charcoal one pound.

2. Mealed-powder one pound, charcoal nine ounces.

23. WATER BALLOONS.

1. Mealed-powder two pounds, salt-petre four pounds, sulphur two pounds, antimony four ounces, saw-dust four ounces, glass-dust one ounce and a-quarter.

2. Mealed-powder three pounds, salt-petre four pounds and a-half, sulphur one pound and a-half, antimony four ounces.

24. WHEEL CASES.

1. Mealed-powder two pounds, salt-petre four ounces, steel-filings six ounces.

2. Mealed-powder two pounds, salt-petre twelve ounces, steel-filings three ounces.

3. Mealed-powder four pounds, salt-petre one pound, sulphur eight ounces, charcoal four ounces and a-half.

4. Mealed-powder eight ounces, salt-petre four ounces, saw-dust one ounce and a-half, charcoal one ounce.

5. Mealed-powder twelve ounces, saw-dust half an ounce, charcoal one ounce.

6. Salt-petre one pound nine ounces, sulphur four ounces, charcoal four ounces and a-half.

25. SLOW FIRE FOR WHEELS.

1. Mealed-powder one ounce and a-half, sulphur two ounces, salt-petre four ounces.

2. Antimony one ounce six drams, sulphur one ounce, salt-petre four ounces.

26. A DEAD FIRE FOR WHEELS.

Salt-petre one ounce and a-half, sulphur a quarter of an ounce, antimony two drams, lapis calaminaris a quarter of an ounce.

27. FOR STANDING OR FIXED CASES.

1. Mealed-powder two pounds, salt-petre one pound, sulphur half-a-pound, charcoal half-a-pound.

2. Mealed-powder one pound, salt-petre half-a-pound, steel-dust four ounces.

3. Mealed-powder ten ounces, charcoal two ounces.

4. Mealed-powder half-a-pound, sulphur two ounces.

5. Mealed-powder one pound and-a-half, saw-dust three-quarters of an ounce, charcoal two ounces and a-half.

28. FOR SUN CASES.

1. Mealed-powder two pounds two ounces, salt-petre five ounces, sulphur one ounce, steel-dust twelve ounces.

2. Mealed-powder one pound and a-half, salt-petre three ounces, steel-dust three ounces and three-quarters.

29. FOR SPIRAL WHEELS.

Mealed-powder fourteen ounces, salt-petre one pound and a-half, sulphur six ounces, glass-dust fourteen ounces.

30. GLOBES.

Salt-petre six ounces, sulphur two pounds, camphor two ounces, antimony four ounces.

31. SERPENTS FOR POTS DES BRINS.

Mealed-powder ten ounces, salt-petre six ounces, charcoal one ounce and a-half.

32. FIRES OF DIFFERENT COLOURS.

_White Fire._--Gunpowder two parts, steel filings one part; for a pale white add a little camphor. Raspings of ivory give a flame of a silver colour, somewhat dazzling to the eyes.

_Red Fire._--Gunpowder two parts, iron-sand of the first order one part. Greek pitch produces a flame somewhat red, but more inclined to a bronze colour.

Common black pitch produces a dusky flame, like a thick smoke, very essential in producing a medium of intolerable obscurity.

Sulphur, mixed in a moderate quantity, makes the flame appear of a blue cast.

Sal ammoniac and verdigris produce a flame inclined to green.

Raspings of yellow amber give to the flame a lemon colour.

Crude antimony a kind of russet colour.

33. FOR JETS OF FIRE.

When the inner diameter of the cases is not more than six lines the following must be the proportions.

_Chinese Fire._--Mealed-powder one pound, salt-petre one pound, sulphur eight ounces, charcoal two ounces.

_White Fire._--Iron-sand of the first order eight ounces, mealed-powder eight ounces, salt-petre one pound, sulphur three ounces, charcoal three ounces.

But when their calibre is from eight to twelve lines, the following are the proportions.

_White Fire._--Mealed-powder one pound, salt-petre one pound, sulphur eight ounces, charcoal two ounces.

_Chinese Fire._--Salt-petre one pound four ounces, sulphur five ounces, charcoal five ounces, iron-sand of the third order twelve ounces.

_Brilliant Fire._--Mealed-powder one pound, iron-sand five ounces.

FOR JETS OF LARGER DIMENSIONS.

_Chinese Fire._--Salt-petre one pound four ounces, sulphur seven ounces, charcoal five ounces, and twelve ounces of a compound of the six different kinds of sand.

34. SPARKLING COMPOSITIONS FOR CHOAKED CASES.

_For Black._--Mealed-powder and charcoal.

_For White._--Salt-petre, sulphur, and charcoal.

_For Grey._--Mealed-powder, salt-petre, sulphur, and charcoal.

_For Red._--Mealed-powder, charcoal, and saw-dust.

These may be used in any proportion the practitioner may think proper, for a little experience will prove to him that various colours of fire may be produced by only varying the proportions or order of the ingredients, or by rendering them alternately predominant. The same observation will apply to many other cases of a similar nature.

SECTION VIII.

COMPOUND FIRE-WORKS.

Compound Fire-Works are those resulting from the combination of the single or more simple kind; principally those which we have already described. The number and variety of figures, and the modification of which they are susceptible, is almost endless, and to describe all, or the greater part of them, would far exceed the limits of our MANUAL. We shall therefore consider it sufficient to select such specimens of simple arrangement as will form a proper introduction to those which are more complex; in which latter case the young Pyrotechnist must be left to his own ingenuity, which will readily dictate to him a greater variety than it would be possible for us to describe.

1. GIRANDOLE[15] CHESTS OF SERPENTS.

The first combination which would naturally suggest itself to the uninformed is that of a number of Serpents so arranged as to take fire all at the same time, and in the end to burst and make a loud report.

This combination is a nest of Serpents; the case or box containing them must be made of strong paste-board, in dimensions equal to the number to be inserted. The piece which forms the top must be perforated in as many places, answering to the number of Serpents intended to be fired; they need not be far from each other. At the bottom of the box must be put a little mealed-powder for the mouths of the Serpents to rest upon, which latter must be rubbed with a little wet mealed-powder, in order that they may take fire immediately. To communicate fire to the powder at the bottom of the box, one of the Serpent cases must be filled with a slow composition, left open at the top, and inserted about the middle of the box: this case being lighted, it will burn for a short time, or till it reaches the bottom, when a sudden noise will be heard, and all the Serpents thrown in various directions into the air.

This mode of firing Serpents, though puerile in its contrivance, and simple in its production, generally affords much amusement to the spectators, which proceeds principally from the variety of directions given to the Serpents; which latter is a consequence of their being placed somewhat carelessly in the box, and being trajected at different angles from the same plane.

2. GIRANDOLE CHESTS OF ROCKETS.

These chests should be made of some thin boards, in dimensions proportionate to the number of Rockets. The Rockets best adapted are those of from two, to six ounces. The depth of the box should be somewhat more than the length of the Rockets with their sticks. The top (being perforated properly to receive the sticks,) must be fixed at right angles in the chest, and as far from the top of it as the length of the Rocket cases, including the cap, if such are used. The distance between each Rocket must be such that they may stand without touching each other. From one hole to another must be cut a groove, in depth sufficient to receive a piece of quick-match, which must be laid from hole to hole in like manner. Below the top, at about two thirds the length of the rods, must be fixed the bottom, perforated in the same manner, save in the size of the holes, which will be somewhat less owing to the dimensions of the rods. The match being laid as above, take some sky-rockets, and having put a piece of the same match up the cavity of each, left extending a little below the mouth of the Rocket, which latter should be rubbed a little with mealed-powder, wetted with some liquid, before given. The Rockets and chest being thus ready, put the rod through the holes in the top and bottom of the chest, in such manner that their mouths may just rest on the quick-match in the grooves, by which all the Rockets will be fired at the same time; for by lighting any part of the match, it will communicate to the whole of them in an instant. For convenience in placing the rod through the lower holes, a small door should be made in one side of the chest, without this it will be difficult to get the rods in their right places.

Previous to the exhibition of these flights of Rockets, they should be covered over, or set in some safe place, or they will be in danger of being set on fire by sparks from other works.

3. POTS DES BRINS.

These are large paper cylinders, filled with powder, Stars, Sparks, &c. They are generally made of paste-board, and about four diameters long; they should be choaked at one end like common cases. They are generally exhibited in numbers, fixed on a plank of some kind, in the following manner: on the under side of your plank, make as many grooves as you intend to have rows of pots, then at a little distance from each other, and exactly over the grooves, fix as many pegs, about three fourths or one diameter high; then through the centre of each peg bore a hole down to the groove at bottom, and on every peg fix and glue a pot, the mouth of which must fit tight on the peg; then through all the holes run a quick-match, one end of which must go into the pot, and the other into the groove, which must have a match laid in it from end to end, and covered with paper, so that when lighted at one end it may discharge the whole almost instantaneously. In each pot put about one ounce of mealed and corn powder; then in some put Stars, and in others Rain, Snakes, Serpents, Crackers, Sparks, &c. When they are loaded, secure their mouths by putting paper over each.

When fired in considerable numbers, these Pots des Brins, from their affording so great a variety of fires, produce a most pleasing exhibition.

4. JETS OF FIRE.

These are a kind of fixed Rocket, the effect of which is to throw up into the air Jets of Fire, similar in some respects to those produced by water. If a number of such Rockets be placed horizontally on the same line, it may be easily seen that the fire they emit, will nearly resemble a sheet of water, arranging itself in the form of a cascade. When the Rockets are arranged in a circular form, like the radii and periphery of a circle, they form what is termed a _fixed Sun_.

To procure these Jets of Fire, the cartridge for brilliant fires must in thickness be equal to a fourth part of the diameter, and for Chinese Fires only a sixth part of the same.

The cartridge must be loaded on a nipple, having a point equal in length to the same diameter, and in thickness equal to a fourth part of it; but, from the effect of the fire, the mouth generally becomes larger than is requisite; but this may be prevented, by charging the cartridge after the manner of the Chinese, who fill it to a height equal to a fourth part of the diameter with clay; this must be rammed down as if it were gunpowder.

When the charge is completed with the composition you have made choice of, the cartridge must be closed with a tompion of wood, above which it must be choaked.

The train or match must be of the same composition as that employed for loading; otherwise the dilatation of the air, contained in the hole made by the piercer, would cause the Jet to burst.

Clayed Rockets may be pierced with two holes near the neck, in order to have three Jets on the same plan.

If a kind of top, pierced with a number of holes, be added to them, they will nearly imitate a bubbling fountain.

Jets intended to represent sheets of fire, ought not to be choaked. They must be placed in a horizontal position, or inclined a little upwards or downwards.

If to the top of the cartridge be attached a tin cylindrical cap, terminating in a flat, long, narrow mouth, (similar to those attached to garden watering pots,) the stream of fire will be very much extended, and the beauty of the exhibition increased. The composition for this article is given in the table, section 7.

5. CHINESE FOUNTAIN.

Provide a piece of dry wood, about six or seven feet long, and about two and a-half inches square; at the distance of sixteen inches from the top of this piece, (supposing it be seven feet long, and fixed perpendicular,) must be fixed a shelf, sixteen inches long, and in width about two and a-half inches, and in thickness about three-quarters. Below this shelf must be fixed three or four other shelves of the same width and thickness, but in length increasing eight inches successively as they go towards the bottom. They must be fixed the same distance from each other as the first one from the top.

Now on the top of the post, insert (into a hole of proper dimensions) a gerbe, or fire-pump; on the first shelf insert after the same manner two gerbes, on the second three, on the third four, on the fourth five, and on the bottom shelf six:--They must be so placed, that the next above stand exactly over the middle of the intervals of those below. The gerbes should be placed so that their mouths incline a little forwards; if this be not done, the stars thrown out of the cases will strike against the shelf above, and produce but little of that effect, which, when properly arranged, renders them so beautiful.

A proper connection must be formed with your leaders, between the different cases; beginning at the top, and carrying it downward to every one of them. The top one is to be lighted first.

The Pyramid, or Fountain complete, is represented by fig. 25.

6. PYRAMID OF FLOWER POTS.

In general construction, this article is exactly similar to the one just described; but in place of gerbes, or fire-pumps, it is loaded with mortars, filled with Serpents, Crackers, &c. and having in the centre of each a case filled with spur-fire. The mortars should be made of paste-board, wound two or three times round a cylinder, about four inches diameter, and well secured by glue, by which means their bottoms and tops are fixed to them.

The spur-fire, which is the chief ornament of these pieces, is prepared as follows:--It has been said that excellence can never be obtained, without overcoming commensurate difficulties; this is certainly verified in the preparation of this composition; for nothing can exceed the difficulty and trouble in preparing it, and nothing can exceed the beauty of its appearance _when properly prepared_. It is said to be the invention of the Chinese, and is certainly the most beautiful and curious of any yet known.

The principal care in the preparation, is, to have the ingredients of the very best quality; next to that is the well grinding and mixing them together.

The proportion of the ingredients is salt-petre four pounds and a-half, sulphur two pounds, and lamp-black one pound eight ounces. One great difficulty is in the mixing these ingredients together; it is best to sift the salt-petre and sulphur together first, and then put them into a marble mortar, and the lamp-black with them, which must be worked down by degrees with a wooden pestle, till all the ingredients appear of one colour, which will be somewhat grayish, but more inclined to black; when this is done drive a little into a case for trial, and fire it in a dark place; if sparks come out in the form of _stars_ or _pinks_, and in clusters, spreading well without any other sparks, it may be considered good: if it appear drossy, and the stars not full, it is not mixed enough; but if the pinks are very small, and soon break, it is indicative of an excess of rubbing; if the excess is great, it will be too fierce, and hardly show any stars: on the other hand, if the rubbing or mixture is in defect, it will be too weak, and produce nothing but an obscure or black smoke.

This composition is generally rammed in one or two ounce cases, about five or six inches long; care must be taken not to ram it too hard. The aperture at the choak should not be so wide as is usually given to other choaked cases.

It is somewhat remarkable, that the composition should be improved by being kept in the cases; but it is found that they always play better, if suffered to stand a time after they are filled.

In preparing the Pyramid of Flower Pots, the cases of spur-fire are to be placed in the middle of the mortars, and be connected by leaders, so that they may all be fired together. The cases will first play off in a very pretty manner; and when exhausted, the fire from them communicates to the powder at the bottom of the mortars, and this suddenly taking fire, all blow up simultaneously, and scatter their luminous fragments in the air; the serpents hiss, the crackers bounce, and the illuminated stars fly in all directions, producing considerable amusement and surprise, and forming an excellent conclusion to a small exhibition.

This beautiful composition is also susceptible of other representations, many of which may without the least danger be exhibited within a room, as well as in the open air; it is really of so innocent a nature, that it may be (though improperly) called a _cold fire_; for it is found that when well made, the sparks will not burn a handkerchief when held in the midst of them; they may be held in the hand with perfect safety; if the sparks fall a short distance upon the hand, you feel them like drops of rain.

A pretty exhibition may be produced by placing a number of spur-fires round a transparent pyramid of paper, and fired in a room, or in the open air. In all cases, and every variety of exhibition, this fire is very beautiful, and will always repay the labour of preparation.

7. WHEELS.