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When these materials have been weighed, the saltpetre and charcoal must be three times sifted through a hair sieve, in order that they may be well mixed : the iron sand is then to be moistened with good brandy, to make the sulphur adhere, and they must be thoroughly incorporated. The sand thus sulphured must be spread over the mixture of saltpetre and charcoal, and the whole must be mixed together by spreading it over a table with a spatula.

2. A shower of fire.—To form a shower of fire, mould small paper cartridges on an iron rod two lines and a half in diameter, and make them two inches and a half in length. They must not be choked, it being sufficient to twist the end of the cartridge, and having put the iron rod into it to beat it, in order to make it assume its proper form. When the cartridges are filled, which is done by immersing them in the composition, fold down the other end, and then apply a match. This will fill the surrounding air with an undulating fire. The following compositions are given as proper for meteors of this kind. 1; Chinese fire —Mealed gunpowder one pound, sulphur two ounces, iron-sand of the first order five ounces. 2. Ancient fire.—Mealed gunpowder one pound, charcoal two ounces. 3. A brilliant fire.—Mealed gunpowder one pound, iron-filings four ounces. The first of these compositions is thought to be the most beautiful.

3. Sparks, differing only from stars in their size and duration, are thus prepared:—Put into an earthen vessel an ounce of mealed gunpowder, two ounces of pulverised saltpetre, one ounce of liquid saltpetre, and four ounces of camphor reduced to powder; pour over this mixture some gum-water, or brandy in which gum has been dissolved, till the composition becomes of the consistence of thick soup. Then take some lint which has been soaked in brandy, or in vinegar, or even in a solution of saltpetre, and, being dried and unravelled, throw into the mixture such a quantity of it as is sufficient to absorb it entirely, taking care to stir it well...This composition may be formed into small balls about the size of a pea, and being dried in the shade, and sprinkled with mealed powder, they will readily catch fire.

o may also be made thus:–Take saw-dust of fir, poplar, &c., and boil it in water in which saltpetre has been dissolved. When the water has boiled some time, it is to be poured off, that the saw-dust may remain in the vessel. When nearly dry, it is to be spread out on a table, and sprinkled with sulphur sisted through a very fine sieve, to which may be added a little mealed powder. 4. Golden rain.—Some rockets, which, as they fall, make small undulations in the air, called by French writers fusées chevelues, and by us bearded rockets, finish with a kind of shower of fire, which is called golden rain, thus constructed:-Fill the barrels of some goose quills with the composition of flying rockets (for which see onward), and place upon the mouth of each a little moist gunpowder, both to keep in the composition, and to serve as a match. If flying rockets be then loaded with these quills, the explosion of them will terminate in a beau. tiful shower of fire, to which the name of golden rain has been given. 5. Globes which burn on the water.—To make a spherical fireball, construct a hollowwooden globe of any size, and let its thickness be about oneninth of its diameter. Into the upper hemisphere insert a right concave cylinder, the breadth of which may be equal to one-fifth of the diameter. A petard, loaded with good grained gunpowder, is to be introduced at the bottom of it, and to be placed horizontally ; then the aperture is ck'sed with a wooden tompion dipped in pitch, and over the whole of this part a quantity of lead is melted sufficient to * the globe sink: if the globe be now placed in the water, the lead by its gravity will make the aperture tend directly downwards, and keep in a perpendicular direction the cylinder, to which fire must have been F. applied. To ascertain whether the ead, which has been added to the globe, renders its weight equal to that of an equal volume of water, rub the globe over with pitch or grease, and make a trial, by placing it in the water. The composition with which the globe must be loaded is as follows: to a pound of grained powder add thirty-two pounds of saltpetre reduced to fine flour, eight pounds of sulphur, one ounce of scrapings of ivory, and eight pounds of saw-dust previously boiled in a solution of saltpetre, and dried in the shade, or in the sun. Or to two pounds of bruised gunpowder add twelve pounds of saltpetre, six pounds of suiphur, four pounds of iron filings, and one pound of Greek pitch. It is not necessary that this composition should be beaten so fine as that intended for rockets: it requires neither to be pulverised nor sisted; it is sufficient to be well mixed and incorporated. But, to prevent it from becoming too dry, it will be proper to besprinkle it with a little oil, or any other liquid susceptible of inflammation. 6. Of globes which leap or roll on the ground.— Having constructed a wooden globe with a cylinder similar to the above described, and having loaded it with the same composition, introduce into it four so. or even more, loaded with good grained gunpowder to their orifices, which must be well stopped with paper or tow If a globe, prepared in this manner, be fired by means of a match, it will leap about, as it burns, on a smooth horizontal plane, according as the petards are set on fire. Instead of placing these petards in the inside, they may be affixed to the exterior surface of the globe; which they will make to roll and leap as they catch fire. They may be applied in any manner to the surface of the globe. 7. A similar globe may be made to roll about on a horizontal plane, with a very rapid motion. Construct two equal hemispheres of pasteboard, and adjust in one of them three common rockets filled and pierced like flying rockets that have no petard : these rockets must not exceed the interior breadth of the hemisphere, and ought to be arranged in such a manner that the head of the one shall correspond to the tail of the other. The rockets being arranged, join the two hemispheres, by cementing them together with strong paper, in such a manner that they shall not separate, while the globe is moving and turning, at the same time that the rockets produce their effect. To set fire to the first, make a hole in the globe opposite to the tail of it, and introduce into it a match. This match will communicate fire to the first rocket; which, when consumed, will set fire to the second by means of another match, and so on to the rest; so that the globe, if placed on a smooth horizontal plane, will be kept in continual motion. It is here to be observed that a few more holes must be made in the globe, otherwise it will burst. The two hemispheres of pasteboard may be prepared in the following manner:—Construct a very round globe of solid wood, and cover it with melted wax; then cement over it several bands of coarse paper, about two inches in breadth, giving it several coats of this kind, to the thickness of about two lines. Or, which will be still easier and better, having dissolved, in glue water, some of the pulp employed by the papermakers, cover with it the surface of the globe; then dry it gradually at a slow fire, and cut it through in the middle; by which means you will have two strong hemispheres. The wooden globe may be easily separated from the pasteboard by means of heat; for if the whole be applied to a strong fire the wax will dissolve, so that the globe may be drawn out: instead of melted wax, soap may be employed. 8 Of aerial globes, called bombs.-These globes are called aerial because they are thrown into the air from a mortar, which is a short thick piece of artillery of a large calibre. And though these globes are of wood, and have a suitable thickness, namely, equal to the twelfth part of their diameters, if too much powder be put into the mortar they will not be able to resist its force; the charge of powder therefore must be proportioned to the globe to be ejected. The usual quantity is an ounce of powder for a globe of four pounds weight; two ounces for one of eight, and so on. As the chamber of the mortar may be too large to contain the exact quantity of powder sufficient for the fire-ball, which ought to be placed immediately above the powder, in order that it may be expelled and set on fire at the same time, another mortar may be constructed of wood, or of

pasteboard with a wooden bottom: it ought to be put into a large iron mortar, and to be loaded with a quantity of powder proportioned to the weight of the globe. This small mortar must be of light wood, or of paper pasted together, and rolled up in the form of a cylinder, or truncated cone, the bottom excepted; which, as already said, must be of wood. The chamber for the powder must be pierced obliquely, with a small gimlet; so that, the aperture corresponding to the aperture of the metal mortar, the fire applied to the latter may be communicated to the powder which is at the bottom of the chamber, immediately below the globe. By this means the globe will catch fire, and make an agreeable noise as it rises into the air; but it would not succeed so well if any vacuity were left between the powder and the globe. A profile or perpendicular section of such a globe is represented by the right-angled parallelogram, the breadth of which is nearly equal to the height. The thickness of the wood, towards the two sides, is equal, as above said, to the twelfth part of the diameter of the globe; and the thickness of the cover is double the preceding, or equal to a sixth part of the diameter. The height of the chamber where the match is applied, and which is terminated by a semicircle, is equal to the fourth part of the breadth; and its breadth is equal to the sixth part. We must here observe that it is dangerous to put wooden covers on aérial balloons or globes; for these covers may be so heavy as to wound those on whom they happen to fall. It will be sufficient to place turf or hay above the globe, in order that the powder may experience some resistance. The globe must be filled with several pieces of cane or common reed, equal in length to the interior height of the globe, and charged with a slow composition, made of three ounces of pounded gunpowder, an ounce of sulphur moistened with a small quantity of petroleum oil, and two ounces of charcoal; and in order that these reeds or canes may catch fire sooner, and with more facility, they must be charged at the lower ends, which rest on the bottom of the globe, with pulverised gunpowder moistened in the same manner with petroleum oil, or well besprinkled with brandy, and then dried. The bottom of the globe ought to be covered with a little gunpowder half pulverised and half grained; which, when set on fire, by means of a match applied to the end of the chamber, will set fire to the lower part of the reed. But care must have been taken to fill the chamber with a composition similar to that in the reeds, or with another slow composition made of eight ounces of gunpowder, four ounces of saltpetre, two ounces of sulphur, and one ounce of charcoal: the whole must be well pounded and mixed. Instead of reeds, the globe may be charged with running rockets, or paper petards, and a quantity of fiery stars or sparks mixed with pulverised gunpowder, placed without any order above these petards, which must be choked at unequal heights, that they may perform their effect at different times. These globes may be constructed in various other ways, which it would be tedious here to enumerate. We shall only observe that, when loaded, they must be well covered at the top; they must be wrapped up in a F. of cloth dipped in glue, and a piece of woollen cloth must be tied round them, so as to cover the hole which contains the match. 9. Jets of fire.—Jets of fire are a kind of fixed rockets, the effect of which is to throw up into the air jets of fire, similar to jets of water. They serve also to represent cascades: for if a series of such rockets be placed horizontally on the same line, it may be easily seen that the fire they emit will resemble a sheet of water. When arranged in a circular form, like the radii of a circle, they form what is called a fixed sun. To form jets of this kind, the cartridge for brilliant fires must, in thickness, be equal to a fourth part of the diameter, and, for Chinese fire, only to a sixth art. p The cartridge is loaded on a nipple, having a point equal in length to the same diameter, and in thickness to a fourth part of it; but, as it generally happens that the mouth of the jet becomes larger than is necessary for the effect of the fire, you must begin to charge the cartridge, as the Chinese do, by filling it to a height equal to a fourth part of the diameter with clay, which must be rammed down as if it were gunpowder. By these means the jet will ascend much higher. When the charge is completed with the composition you have made choice of, the cartridge must be close with a tompion of wood, above which it must be choked. 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 ierced with two holes near the neck, in order to ave three jets in the same plane. If a kind of top, pierced with a number of holes, be added to them, they will imitate a bubbling fountain. Jets intended for representing sheets of fire ought not to be choked. They must be placed in a horizontal position, or inclined a little downwards. It appears to us that they might be choked so as to form a kind of slit, and be pierced in the same manner; which would contribute to extend the sheet of fire still farther. A kind of long narrow mouth might even be provided for this particular purpose.

Principal compositions for jets of fire.

1st. Jets of five lines, or less, of interior diameter.

Chinese fire.—Saltpetre one pound, pulverised gunpowder one pound, sulphur eight ounces, charcoal two ounces.

White fire.—Saltpetre one pound, pulverised gunpowder eight ounces, sulphur three ounces, charcoal two ounces, iron sand of the first order eight ounces. 2d. Jets of from ten to twelve lines in diameter.

Brilliant fire.—Pulverised gunpowder one pound, iron filings of a mean size five ounces.

White fire.—Saltpetre one pound, pulverised gunpowder one pound, sulphur eight ounces, charcoal two ounces.

Chinese fire.—Saltpetre one pound four ounces, sulphur five ounces, sand of the third order twelve ounces.

3d. Jets of fifteen or eighteen lines in diameter Chinese fire.—Saltpetre one pound fout ounces, sulphur seven ounces, charcoal five ounces, of the six different kinds of sand mixed twelve ounces. Père d'Incarville, in his memoirs on this subject, gives various other proportions for the composition of these jets; but we must confine ourselves to what has been here said, and refer the reader to the author's memoirs, which will be found in the Manuel de l'Artificier. The saltpetre, pulverised gunpowder, and charcoal, are three times sifted through a hair sieve. The iron sand is besprinkled with sulphur, after being moistened with a little brandy, that the sulphur may adhere to it; and they are then mixed together: the sulphured sand is then spread over the first mixture, and the whole is mixed with a ladle only; for if a sieve were employed, it would separate the sand from the other materials. When sand larger than that of the second order is used, the composition is moistened with brandy, so that it forms itself into balls, and the jets are then loaded: if there were too much moisture, the sand would not perform its effect. 10. Offires of different colors.-It is much to be wished that, for the sake of variety, different colors could be given to these fire-works at pleasure; but, though we are acquainted with several materials which communicate to flame various colors, it has hitherto been possible to introduce only a very few colors into that of inflamed gunpowder. To make white fire, the gunpowder must be mixed with iron or rather steel filings. To make red fire, iron sand of the first order must be employed in the same manner. As copper filings, when thrown into a flame, render it green, it might be concluded that, if mixed with gunpowder, it would produce a green flame; but this experiment does not succeed. It is supposed that the flame is too ardent, and consumes the inflammable part of the copper too soon. But it is probable that a sufficient number of trials have not yet been made; for is it not possible to lessen the force of gunpowder in a considerable degree, by increasing the dose of the charcoal 2 However the following are a few of those materials which, in books on pyrotechny, are said to possess the property of communicating various colors to fire-works. Camphor mixed with the composition makes the flame to appear of a pale white color. Raspings op ivory give a clear flame of a silver color, inclining a little to that of lead; or rather a white dazzling flame. Greek pitch produces a reddish flame, of a bronze color. Black pitch, a dusky flame, like a thick smoke, which obscures the atmosphere. Sulphur, mixed in a moderate guantity, makes the flame appear bluish. Sal ammoniac and verdigris give a greenish. flame. Raspings of yellow amber communicate to the flame a lemon color. Crude antimony gives a russet color.

Borax ought to produce a blue flame; for spirit of wine, in which sedative salt, one of the component parts of borax, is dissolved by the means of heat, burns with a beautiful green flame. Much, however, still remains to be done in regard to this subject; but it would add to the beauty of artificial fire-works, if they could be varied by giving them different colors: this would be creating for the eyes a new pleasure. 11. Composition of apaste proper for representing animals, and other devices in fire.—It is to the Chinese also that we are indebted for this method of representing figures with fire. For this purpose, take sulphur reduced to an impalpable powder, and, having formed it into a paste with starch, cover with it the figure you are desirous of representing on fire: it is here to be observed that the figure must first be coated over with clay, to prevent it from being burnt. When the figure has been covered with this paste, besprinkle it while still moist with pulverised gunpowder; and, when the whole is perfectly dry, arrange some small matches on the principal parts of it, that the fire may be speedily communicated to it on all sides. The same paste may be employed on figures of clay, to form devices and various designs. Thus, for example, festoons, garlands, and other ornaments, the flowers of which might be imitated by fire of different colors, could be formed on the frieze of a piece of architecture, covered with plaster. The Chinese imitate grapes exceedingly well, by mixing pounded sulphur with the pulp of the jujube instead of flour paste. 12. Of suns both fired and moveable.—None of the pyrotechnic inventions can be employed with so much success, in artificial fire-works, as suns; of which there are two kinds, fixed and revolving: the method of constructing both is very simple. or fixed suns, cause to be constructed a round piece of wood, into the circumference of which can be screwed twelve or fifteen pieces in the form of radii; and to these radii attach jets of fire, the composition of which has been already described, so that they may appear as radii tending to the same centre, the mouth of the jet being towards the circumference. Apply a match in such a manner that the fire communicated at the centre may be conveyed, at the same time, to the mouth of each of the jets; by which means, each throwing out its fire, there will be produced the appearance of a radiating sun. We here suppose that the wheel is placed in a position perpendicular to the horizon. These rockets or jets may be so arranged as to cross each other in an angular manner; in which case, instead of a sun, you will have a star, or a sort of cross resembling that of Malta. Some of these suns are made also with several rows of jets: these are called glories. Revolving suns may be constructed in this manner:—Provide a wooden wheel, of any size at pleasure, and brought into perfect equilibrium around its centre, in order that the least effort may make it turn round. Attach to the circumference of it fire-jets placed in the direction of the circumference; they must not be choked at the bottom, and ought to be arranged in such a Vol. XVIII.

manner that the mouth of the one shall be near the bottom of the other, so that when the fire of the one is ended it may immediately proceed to another. It may easily be perceived that, when fire is applied to one of these jets, the recoil of the rocket will make the wheel turn round, unless it be too large and ponderous: for this reason, when these suns are of a considerable size, that is, when they consist for example of twenty rockets, fire must be communicated at the same time to the first, the sixth, the eleventh, and the sixteenth; from which it will proceed to the second, the seventh, the twelfth, the seventeenth, and so on. These four rockets will make the wheel turn round with rapidity. If two similar suns be placed one behind the other, and made to turn in a contrary direction, they will produce a very pretty effect of crossfire. Three or four suns, with horizontal axes passed through them, might be implanted in a vertical axis, moveable in the middle of a table. These suns, revolving around the table, will seem to pursue each other. It may be easily perceived that, to make them turn around the table, they must be fixed on their axes, and these axes, at the place where they rest on the table, ought to be furnished with a very moveable roller. 13. 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 threequarters 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 ahalf, 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 |. if you would have a great number of ounces, you must cut the paper longer, or join them after they are made; but, if they are made very long before they 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. 14. To make squibs.-First make the cases, of about six inches in length, by rolling slips of stoutcartridge paper three times round aroller, 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 - U

three times; when this is done point it with touch-paper, which should be pasted on that part which touches the case, otherwise it is liable to drop off.

*...* The apparatus chiefly used in making fireworks consists of solid wooden cylinders, called formers, for rolling the cases on ; similar cylinders, either of wood or metal, for ramming down the composition; moulds for holding the cases while filling; a machine for contracting the cavity of the cases; another for grinding the mateterials; and a particular apparatus for boring some cases after they are filled.

IMITATIve FIREworks.

Take a paper that is blacked on both sides, or, instead of black, the paper may be colored on each side with a deep blue, which will be still better for such as are to be seen through transparent papers. It must be of a proper size for the figure you intend to exhibit. In this paper cut out with a penknife several spaces, and with a piercer make a great number of holes, rather long than round, and at no regular distance from each other. To represent revolving pyramids and globes, the paper must be cut through with a penknife, and the space cut out between each spiral should be three or four times as wide as the spirals themselves. You must observe to cut them so that the pyramid or globe may appear to turn on its axis. The columns that are represented in pieces of architecture, or in jets of fire, must be cut in the same manner, if they are to be represented as turning on their axes. In like manner may be exhibited a great variety of ornaments, cyphers, and medallions, which, when properly colored, cannot fail of producing a most pleasing effect. There should not be a very great diversity of colors, as that would not produce the most agreeable appearance. When these pieces are drawn on a large scale, the architecture or ornaments may be shaded : and, to represent different shades, pieces of colored paper must be pasted over each other, which will produce an effect that would not be expected from transparent paintings. Five or six pieces of paper pasted over each other will be sufficient to represent the strongest shades. To give these pieces the different motions they require, you must first consider the nature of each piece; if, for example, you have cut out the figure of the sun, or of a star, you must construct a wire wheel of the same diameter with those pieces; over this wheel you paste a very thin paper, on which is drawn, with black ink, the spiral figure. The wheel thus prepared is to be placed behind the sun or star, in such a manner that its axis may be exactly opposite the centre of either of those figures. This wheel may be turned by any method you think proper. Now, the wheel being placed directly behind the sun, for example, and very near to it, is to be turned regularly round, and strongly illuminated by candles placed behind it. The lines that form the spiral will then appear, through the spaces cut out from the sun, to proceed from its centre to its circumference, and will resemble

sparks of fire that incessantly suceeed each other. |. same effect will be produced by the star, or by any other figure where the fire is not to appear as proceeding from the circumference of the centre. These two pieces, as well as those that follow, may be of any size, provided you observe the proportion between the parts of the figure and the spiral, which must be wider in larger figures than in small. If the sun, for example, have from six to twelve inches diameter, the width of the strokes that form the spiral need not be more than one-twentieth part of an inch, and the spaces between them, that form the transparent parts, about two-tenths of an inch. If the sun be two feet diameter, the strokes should be one-eighth of an inch, and the space between one-quarter of an inch ; and, if the figure be six feet diameter, the strokes should be one-quarter of an inch and the spaces five twelfths of an inch. These pieces have a pleasing effect when represented of a small size, but the deception is more striking when they are of large dimensions. It will be proper to place those pieces, when of a small size, in a box quite closed on every side, that none of the light may be diffused in the chamber: for which purpose it will be convenient to have a tin door behind the box, to which the candlesticks may be soldered, and the candles more easily lighted. The several figures cut out should be placed in frames, that they may be put alternately in a groove in the fore-part of the box; or there may be two grooves, that the second piece, may be put in before the first is taken out. The wheel must be carefully concealed from the eye of the spectator. Where there is an opportunity of representing these artificial fires by a hole in the partition, they will doubtless have a much more striking effect, as the spectator cannot then conjecture by what means they are produced. It is easy to conceive that, by extending this method, wheels may be constructed with three or four spirals, to which may be given different directions. It is manifest, also, that on the same principle a great variety of transparent figures may be contrived, and which may be all placed before the same spiral lines. To represent cascades of fire.—In cutting out cascades, you must take care to preserve a natural inequality in the parts cut out; for if to save time you should make all the holes with the same pointed tool, the uniformity of the parts will not fail to produce a disagreeable effect. As these cascades are very pleasing when well executed, so they are highly disgusting when imperfect. These are the most difficult pieces to cut out. To produce the apparent motion of these cascades, instead of drawing a spiral you must have a slip of strong paper, of such length as you judge convenient. }. this paper there must be a great number of holes near each other, and made with pointed tools of different dimensions. At each end of the paper, a part, of the same size with the cascade, must be left uncut; and towards those parts the holes must be made a greater distance from each other, When the cascade that is cut out is placed be

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