CHAPTER II.
FIRE-WORKS FOR THEATRICAL PURPOSES.
_Sec. I. Of Puffs, or Bouffées._
The _bouffée_, according to the term used in French, signifies a species of fire, which exhibits itself in _puffs_, or in alternate appearances, more or less brilliant. It is also called the flambeaux of the furies. This description of artificial fire is used in _theatres_, and frequently in ordinary fire-works. It is fired from, and exhibited with, a funnel of tin, or sheet iron, having a hole at the apex of the cone. The hole is to be sufficiently large to admit the fire from a quick match. It is particularly calculated, when a gulf, crater, or the caves of the Cyclops, intended to eject flame, are to be exhibited.
Although many compositions may be used for this purpose, yet the following, which is employed in France, is considered preferable:
_Composition for Bouffées._
Saltpetre 16 oz. Meal-powder 4 oz. Charcoal 8 oz.
When the materials are well mixed, a piece of silk paper is prepared in a round shape, by pressing it on the end of a roller, in the same manner as the ordinary cases. About one ounce of the composition is put into it, on which is placed very lightly two drachms of meal-powder. A double quick-match is now put on the meal-powder, and the paper is closed by pressing it between the fingers. It is then tied with twine. The quick-match is left sufficiently long to pass through the hole at the apex of the cone, in which is introduced the _puff_, being pressed a little at the bottom. The excess of the quick-match, should there be any, is cut off within an inch of the extremity of the funnel. When used, it is inflamed by a lance or port fire. The effect of the puff, in the first place, is to throw out of the funnel, by the meal-powder, a volume of fire, which will cause the appearances before mentioned.
_Sec. II. Of Eruptions._
If the appearance of a volcano, or the effect of a mine is required in a piece, the following method is commonly followed: a tin, sheet-iron, or brass box is provided, either round or square, of nine inches in height, and three inches and a half in diameter, and placed on a wooden stand, sufficiently large to prevent it from overturning.
Three, four, or five ounces of the composition, mentioned in _Sec. i._ of this chapter, is put into it, according to the effect intended to be produced. The composition is pressed a little with the hand, and a piece of quick-match is used. This match projects out of the case, and is secured with a piece of paper, pasted over its circumference.
When the fire is presented to the quick-match, it communicates with rapidity to the inside of the box, or case, which produces an eruption, from twelve to fifteen feet in height. The effect may be made more or less great, by making the boxes of a proportional size, or by using several of them at the same time.
If a mine is the subject of representation, it is necessary to employ some large _marrons_, which should communicate with the boxes, and in such a manner, as that they may operate at the same time.
This exhibition, it is obvious, may be varied according to circumstances, either by employing a larger quantity of the composition in several cases, or by using one or more marrons, or some other descriptions of fire-works, the effect of which is calculated to increase the flame, and to produce the necessary variations.
_Sec. III. Of the Flames._
If a flame is to be represented, as for example, the effect of an incendiary, and its appearance is to be prolonged, the fire from tow being too transient, small iron kettles, of four inches in diameter, and depth, may be used. In these are put three or four ounces of the composition of the _lances of service_, which is moistened with the oil or spirit of turpentine. When set on fire, they will produce a blaze three or four feet in height, and one and a half in diameter. Several may be used, according to the effect required. See the composition for the _lances of service_.
_Sec. IV. Of the Fire-rain._
A variety of compositions for fire-rain are used, which will be noticed, when we speak of the _garnishing_ of rockets, and other fire-works.
Cases are prepared of seven-twelfths of an inch in diameter, and ten inches long, which are choaked in such a manner, as that the hole of communication should be one-third of the diameter of the interior case. They are then charged with the following composition:
_Composition of the fire-rain._
Saltpetre 8 ounces. Sulphur 4 do. Meal powder 16 ounces. Charcoal of oak 2½ do. Pitcoal 2½ do.
When the cases are charged and primed, they are tied upon a rod, having a groove cut in its length. In the inside of the groove, is a port-fire, or leader, which is tied to the cases with twine, and the groove is then covered with several pieces of paper, in the shape of a band.
This precaution is thus taken for the theatre, in order to prevent the inflamed port-fire from falling on the stage.
_Sec. V. Of other Compositions for Fire-rain, in Chinese fire._
The composition of Chinese fire, which we will have occasion to mention more fully hereafter, is calculated to exhibit a more brilliant fire, with a steady and uniform effect. It is used principally on the French stage, in large operas. It is charged and used, in all respects, like the preceding.
_Composition of Chinese Fire._
Saltpetre, 8 ounces Meal powder, 16 Sulphur, 4 Charcoal, 2 Powdered cast iron, 10
The elegance of the flame, produced by this mixture, depends entirely upon the effect, which cast iron possesses; and, by its combination with charcoal, sulphur, meal powder, and nitre, while an oxide of iron results from the combustion, we have, likewise, other products, arising from the decomposition of the nitre, and the union of carbon and sulphur respectively with a part of the oxygen of the nitric acid of the nitre. The gunpowder decomposes itself by reason of the nature of its own composition; but the sulphur, charcoal, and iron, decompose the nitric acid of the nitre, in the act of combustion. So that, to produce the effect, an additional quantity of nitre to that which is in the gunpowder, is required in this preparation.
_Sec. VI. Of Thunderbolts. (Foudres F.)_
The thunderbolts are charged in cases of two-thirds of an inch in diameter, in the same manner as cases for wheels and rockets. They are primed, whitened, well pasted, and left to dry. Some preliminary operations are required in their exhibition, as the use of the piercer, the tying of one end of the case, which is to descend first from the top of the theatre, &c. A port-fire is used for setting them off.
_Composition of Thunderbolts._
Meal powder, 6 ounces. Saltpetre, 6 ---- Sulphur, 3 ---- Antimony, 4 drachms.[24]
_Sec. VII. Of Dragons and other Monsters._
In certain pieces, exhibitions of this kind are made. They are formed in such a way, as to make them throw fire from the mouth, nose, and ears, which is blown out into the air. Cases, charged with brilliant fire, are so arranged that their fire may act all at the same time. Puffs may also be produced to go out at the mouth, by means of a tube or funnel, placed behind the monster. These preparations and exhibitions are so susceptible of variations, that, having a previous knowledge of the composition and effect of the fire-work, it may be so arranged as to produce a variety of appearances.
_Sec. VIII. Of Lightning._
The effect of lightning may be shown by several preparations. Lycopodium, or puff-ball, is the substance most commonly employed. When it cannot be procured, rosin may be substituted; and, generally, as the latter is cheaper, it is used. Rosin, reduced to an impalpable powder, and thrown upon a flame, will produce the effect in a remarkable degree, and when blown through a tube, the effect is more striking.
Several fluid substances, when ejected from a syringe on a lighted candle, have the same appearance. Alcohol has this effect. The difficulty of preparing and employing them, has given the lycopodium a preference.
A tin or brass tube, larger at one end than the other, and covered at the former end, with a cover, perforated with holes, similar to the branch of a watering pot, is used for holding the composition, or substance made use of. Through this cover, or lid, a cotton wick is put, which, before lighting, is well soaked in alcohol or spirits of wine. When lighted, the torch or tube, containing the lycopodium, or rosin, is shaken at the smaller extremity; when these substances will pass through the holes in small quantities, and be successively inflamed.
_Sec. IX. Of the Artifice of Destruction._
When, in any exhibition, palaces, castles, or forts are to be demolished, or thrown down, there are about twenty petards fixed on rods. Petards, for this use, are made with cases, and sometimes with wheels. The cases are generally three-quarters of an inch in diameter, charged with grain powder, and choaked at both ends. They are arranged in a zigzag direction.
This series of _crackers_ has a fine effect. It is obvious, that, in all these exhibitions, intelligent artizans may employ various descriptions of artificial fire, where, in particular, it often seems, that there is something yet to be wished for.
_Sec. X. Of the Spur-fire._
The spur-fire is so called, because its fire or sparks resemble the rowel of a spur. It is used in theatres and in rooms. It is the most beautiful of any yet known, and was invented by the Chinese, but greatly improved in Europe.
It requires great care to make it properly. Care ought to be taken that all the ingredients are of the best quality, that the lampblack is neither damp nor clodded, that the saltpetre is the best refined, and the sulphur perfectly pure. This composition is generally rammed into one or two ounce cases, about five or six inches long, but not driven very hard; and the cases must have their concave stroke struck very smooth, and the choak or vent not quite so large as the usual proportion: this charge, when driven, and kept a few months, will be much better than when rammed. If kept dry, it will last many years.
As the beauty of this composition cannot be seen at so great a distance as brilliant fire, it has a better effect in a theatre or room, than in the open air; and may be fired in a chamber, without danger. Its effect is of so innocent a nature, that it has been called _cold fire_; and so extraordinary is the fire produced from this composition, that if well made, the sparks will not burn a handkerchief when held in the midst of them. The hand, brought in contact with the spark, will feel only a sensation similar to that occasioned by the falling of rain. When any of these spurs are fired singly, they are called _artificial fire-pots_; but some of them, placed round a transparent pyramid of paper, and fired in a large room, make a very elegant appearance.
_Composition of Spur-Fire._
1. Saltpetre, 4½ lbs. Sulphur, 2 lbs. Lampblack, 1½ lbs. or, 2. Saltpetre, 1 lb. Sulphur, ½ lb. Lampblack, 4 quarts.
The saltpetre and sulphur must be first mixed together, and sifted, and then put into a marble mortar, and the lampblack with them, which are to be worked by degrees, with a wooden pestle, till all the ingredients appear of one colour, which will be a gray, approaching to black. It is then to be tried by driving a little of it into a case, and fired in a dark place; and if the sparks, which are called _stars_, or _pinks_, come out in clusters, and afterwards spread well, without any other sparks, it is a criterion of its goodness. If any drossy sparks appear, and the stars are not full, it is then not mixed sufficiently: but, if the pinks are very small, and soon break, it is a proof that it has been rubbed too much; for, in this case, few stars will appear. When, on the contrary, the mixture is not rubbed sufficiently, the combustion will be too weak, and lumps, resembling dross, with an obscure smoke, but without stars, will be emitted.
The peculiar effect of this composition is owing to the carbon of the lampblack, one part of which is inflamed, its combustion being supported by the oxygen gas of the atmosphere.
_Sec. XI. Of the coloured Flame of Alcohol._
We have already remarked, in treating of alcohol, that its flame may be changed of various colours, by using certain native substances. See _Alcohol_.
Alcohol, thus mixed, or combined with substances, may be exhibited on certain occasions; for even cotton, when immersed in it, and set on fire, will show the same appearances. Morel remarks, that, if vinegar, a small portion of crude tartar, and common salt, and a still smaller quantity of saltpetre, be mixed together, and distilled, a liquid will be obtained, which burns with great brilliancy. It is doubtful, however, if we judge from analogy, whether either tartar, the salt, or saltpetre, will communicate any peculiar property to the distilled vinegar; for these saline substances will remain unaltered in the distilling vessel. The vinegar, nevertheless, may be obtained in a more concentrated state, being deprived of its colouring and other matter, and the greater part of its water, and, therefore, approach to the state of acetic acid.
With respect to alcohol, it is known to dissolve a variety of saline substances, most of which have the property of changing the colour of its flame. Although we have not made any experiments with the spirits of turpentine, yet we are of opinion, that it may be used with resins, &c. in the same manner. In all cases, it is evident, that the fluid made use of must be inflammable.
_Macquer_ (_Memoirs of the Turin Academy_) made a number of experiments on the solubility of salts in alcohol, and on the different coloured flames, which they produced. The principal results of his experiments, are the following:
Quantity in grains. Salts soluble in 200 Peculiar phenomena grains of spirit. of the flame.
{ Flame, larger, higher, 4 Nitrate of potassa, { more ardent, yellow, { and luminous.
5 Muriate of potassa, { Large, ardent, yellow, { and luminous.
0 Sulphate of soda, Considerably red.
15 Nitrate of soda, { Yellow, luminous, { detonating.
0 Muriate of soda, { Larger, more ardent, { and reddish.
0 Sulphate of ammonia, None.
108 Nitrate of ammonia, Whiter, more luminous.
24 Muriate of ammonia, None.
288 Nitrate of lime, { Larger, more luminous, { red, and decrepitating.
288 Muriate of lime, { Like that of nitrate of { lime.
84 Nitrate of silver, None.
204 Muriate of mercury, { Large, yellow, luminous, { and decrepitating.
4 Nitrate of iron, Red and decrepitating.
36 Muriate of iron, { More white, luminous, { and sparkling.
{ More white, luminous, 48 Nitrate of copper, { and green, much smoke. { The saline residuum { became black and burnt.
48 Muriate of copper, { Fine green, white { and red fulgurations.
The alcohol, he employed, had a specific gravity of 0.840.
_Sec. XII. Of Red fire._
Dr. Ure (_Chemical Dictionary_) informs us, that the beautiful red, which is now frequently used at the theatres, is composed of the following ingredients: 40 parts of dry nitrate of strontia; 13 parts of finely powdered sulphur; 5 parts of chlorate (hyperoxymuriate) of potassa, and 4 parts of sulphuret of antimony. The chlorate of potassa and sulphuret of antimony, should be powdered, separately, in a mortar, and then mixed together on paper; after which they may be added to the other ingredients, previously powdered and mixed. No other kind of mixture than rubbing together on paper is required. Sometimes a little realgar is added to the sulphuret of antimony, and frequently, when the fire burns dim and badly, a very small quantity of very finely powdered charcoal or lampblack will make it perfect.