Читать книгу Artificial Fire-Works - Robert Jones - Страница 7

A

TREATISE

ON

Artificial Fireworks.

SECT. I.

Of Saltpetre.

Saltpetre being the principal ingredient in fireworks, and a volatile body, by reason of its aqueous and aërial parts, is easily rarified by fire; but not so soon when foul and gross, as when purified from its crude and earthy parts, which greatly retard its velocity: therefore, when any quantity of Fireworks are intended to be made, it would be necessary first to examine the saltpetre; for if it be not well cleansed from all impurities, and of a good sort, your works will not have their proper effect, neither will it agree with the standing proportions of compositions: but to prevent accidents I shall proceed with the method of refining it.

How to refine Saltpetre.

Put into a copper, or any other vessel, one hundred weight of rough nitre with about fourteen gallons of clean water, and let it boil gently for half an hour, and as it boils take off the scum; then stir it about in the copper, and before it settles put it into your filtring bags, which must be hung on a rack, with glazed earthen pans under them in which must be sticks laid across for the crystals to adhere to; it must stand in the pans for two or three days to shoot, then take out the crystals and let them dry: the water that remains in the pans boil again for an hour, and strain it into the pans as before, and the saltpetre will be quite clear and transparent; if not, it wants more refining, to do which proceed as usual, till it is well cleansed of all it’s earthy parts.

N. B. Those who do not chuse to procure their saltpetre by the above method, may buy it ready done, which for fireworks in general will do equally as well.

How to pulverise Saltpetre.

Take a copper kettle whose bottom must be spherical, and put into it fourteen pound of refined saltpetre, with two quarts or five pints of clean water; then put the kettle on a slow fire, and when the saltpetre is dissolved, if any impurities arise, skim them off, and keep constantly stirring it with two large spatulas, till all the water exhales; and when done enough, it will appear like white sand, and as fine as flour; but if it should boil too fast, take the kettle off the fire, and set it on some wet sand, which will prevent the nitre from sticking to the kettle. When you have pulverised a quantity of saltpetre, be careful to keep it in a dry place.

How to extract Saltpetre from damaged Gun-Powder.

First you must have some filtring bags, hung on a rack, with glazed earthen pans under them, in the same manner as those for refining saltpetre: then take any quantity of damaged powder, and put it into a copper, with as much clean water as will just cover it; and when it begins to boil take off the scum, and after it has boiled a few minutes, stir it up; then take it out of the copper with a small hand kettle for that purpose, and put some into each bag, beginning at one end of the rack, so that by the time you have got to the last bag, the first will be ready for more; continue thus, till all the bags are full; then take the liquor out of the pans, which boil and filter, as before, two or three times, till the water runs quite clear, which you must let stand in the pans for some time, and the saltpetre will appear at top. Now to get all the saltpetre entirely out of the powder, take the water from the saltpetre already extracted, to which add some fresh water and the dregs of the powder that remain in the bags, and put them together in a vessel, to stand as long as you please, and when you want to extract the nitre, you must proceed with this mixture as with the powder at first, by which means you will draw out all the saltpetre; but this process must be boiled longer than the first.

Of Sulphur, or Brimstone.

Sulphur is by nature the food of fire, and one of the principal ingredients in gunpowder, and almost in all compositions of fireworks; therefore great care ought to be taken, of its being good and brought to the highest perfection. Now to know when the sulphur is good, you are to observe that it be of a high yellow, and if, when held in one’s hand, it crackles and bounces, it is a sign that it is fresh and good: but as the method of reducing brimstone to a powder, is very troublesome to do, it is better to buy the flower ready made, which is done in large quantities, and in great perfection: but when a grand collection of fireworks are to be made, the strongest and best sulphur to use, is the lump brimstone ground in the same manner as gun powder, which we shall treat of in the following part of the treatise.

How to prepare Charcoal for Fireworks.

Charcoal being a preservative by which the saltpetre and the brimstone is made into gun-powder, by preventing the sulphur from suffocating the strong and windy exhalation of the nitre. There are several sorts of wood made use of for this purpose; some prefer hazle, others willow and alder; but there being so little difference, you may make use of either which is most convenient to be got. And the method of burning the wood is this: Cut it in pieces about one or two feet long, then split each piece in four parts; scale off the bark and hard knots, and dry them in the sun or in an oven, then make in the earth a square hole, and line it with bricks, in which lay the wood, crossing one another, and set it on fire; when thoroughly lighted and in a flame, cover the hole with boards, and fling earth over them close, to prevent the air from getting in, yet so as not to fall among the charcoal, and when it has lain thus for twenty-four hours, take out the coals and lay them in a dry place for use. It is to be observed that charcoal for fireworks must always be soft and well burnt, which may be bought ready done.

To make Artificial Camphor.

Camphor, in the Materia medica, “is a body of a particular nature, being neither a resin, nor a volatile salt, nor an oil, nor a juice, nor a bitumen, nor a gum, but a mixed substance, dry, white, transparent and brittle, of a strong and penetrating smell. The Indians distinguish two kinds of it, a finer and a coarser; the finer is the produce of Borneo and Sumatra, is very rare, and is hardly ever sent into Europe; the coarser is the Japonese kind, which is the common sort, both in the Indies and in Europe.

“The camphor, which we meet with in the shops, is also of two kinds, differing in regard to the degree of their purity, and distinguished by the name of rough and refined camphor. The tree, which produces camphor, is a species of bay tree, every part of which abounds with camphor; but is not collected from it in the manner of resins, but by a sort of chemical process.--The natives of the place where the trees grow, cut the wood and roots into small pieces. And put them into large copper vessels, which they cover with earthen heads, filled with straw; they give a moderate fire under them, and the camphor is raised in form of a white downy matter, and retained among the straw; when the process is over, they shake it out of the straw, and knead it into cakes. These cakes is are not very compact, but easily crumbled to pieces; they are moderately heavy, of a greyish or dusky reddish white in colour, of a pungent smell and acrid taste, and are what we call rough camphor.

“Refined camphor must be chosen of a perfectly clean white colour, very bright and pellucid, of the same smell and taste with the rough, but more acrid and pungent.--It is so volatile that merchants usually inclose it in lin-seed, that the viscosity of that grain may keep its particles together.”

Now there is also an artificial camphor for fireworks, which I shall here give you the method of making; take of gum sandarach pulverised two pound, and of distilled vinegar enough to cover it; put them together in a glass phial, and set it for twenty days in warm horse dung. Then take it out again, and pour it into another phial, with a large mouth to it; and expose it to the sun for a month, and you will have a concreted camphor in form of the crust of bread, and something like the natural camphor: which when you use must be ground to a powder with a little spirits of wine in a mortar. Though we have here taught the method of making artificial camphor, I would not recommend it to those who chuse to make their works to perfection, the natural camphor, being by far the best.

To make the Oil of Camphor.

The oil of camphor, which is sometime used to moisten compositions, is produced by adding to some camphor a little oil of sweet almonds, and working them together in a brass mortar, till it turns to a green oil.

N. B. Those works that have any camphor in their compositions, should be kept as much from air as possible, or the camphor will evaporate.

Of Benjamin.

Benjamin is a resin (much used by perfumers, and sometimes in medicine); it is brought from the Indies, where it is found of different sorts; and distinguished by the following colours, viz. yellow, grey, and brown, but the best is that which is easy to break and full of white spots.

Benjamin is also one of the ingredients in odoriferous fireworks, when reduced to a fine flour; which may be done by observing the following directions. Put into a deep, and narrow earthen pot, three or four ounces of benjamin grossly pounded, cover the pot with paper, which tie very close round the edge; then set the pot on a slow fire, and once in an hour take off the paper, and you will find some flower sticking to it, which return again in the pot; this you must continue till the flower appears white and fine. There is also an oil of benjamin, which is sometimes drawn from the dregs of the flour; it affords a very good scent, and may be used in wet compositions.

Of Gun-powder and its original.

Gun-powder being a principal ingredient in fireworks, it will not be improper to give a short definition of its strange explosive force, and cause of action, which, according to Dr. Shaw’s opinion, of the chemical cause of the explosive force of gun-powder, is as follows. “Each grain of powder consisting of a certain proportion of sulphur, nitre, and coal, the coal presently takes fire, upon contact of the smallest spark: at which time both the sulphur and the nitre immediately melt, and by means of the coal interposed between them, burst into flame; which spreading from grain to grain, propagates the same effect almost instantaneously: whence the whole mass of powder comes to be fired; and as nitre contains both a large proportion of air and water, which are now violently rarified by the heat, a kind of fiery explosive blast is thus produced, wherein the nitre seems, by its aqueous and aërial parts, to act as bellows to the other inflammable bodies, sulphur and coal, to blow them into a flame, and carry off their whole substance in smoke and vapour.”

After having spoke of the nature of powder, I shall in the next place proceed to its original, though somewhat uncertain; but it is imagined to have been invented in the time of Alexander the great, as Philostratus speaks of a city near the river Hypasis in the Indies, that was said to be impregnable and its inhabitants relations of the gods, because they thew thunder and lightning on their enemies; but this perhaps might be the effect of gun-powder, which, not being known by any other people, might very well be said to be thunder and lightning.

This conjecture has been confirmed by some travellers, who assert that it was used in the East Indies, particularly in the Philippine Islands about the year 85, which is 1265 years before it was known in Europe, where they say it was not known till 1350, though, it is said, there is mention made of gunpowder in the registers of the chambers of accounts in France, as early as the year 1338, and Friar Bacon mentions the composition of powder in express terms, in his treatise De nullitate magiae, published at Oxford in the year 1216; but we find from most accounts, that the Germans have the honour of the invention, as is commonly reported.

I should give a description of a machine for the trying of gun powder, but they being so common, it would be needless; yet, would have all those who practice this art, know, that, when they make sky rockets with powder, that it must be of the best sort; but as to wheels, and other common works, any powder will do, only be careful that it is quite dry.

Of the Compositions for Gun-powder of different sorts.

Having treated of the nature of powder, and its original, I shall here give the proportion of each ingredient, necessary for composing the different sorts of gun-powder, it being proper that every one who makes use of powder, should know of what it is composed. Therefore in the first place; I shall set down the several compositions mentioned In Casimir Siemienowicz’s grand art of artillery, in which there are six sorts, viz.

I. Saltpetre one hundred pound, sulphur twenty five pound, and coal twenty five pound.

II. Saltpetre one hundred pound, sulphur eighteen pound, and coal twenty pound.

III. Saltpetre one hundred pound, sulphur twelve pound, and coal fifteen pound.

IV. Saltpetre one hundred pound, sulphur twenty pound, and coal twenty four pound.

V. Saltpetre one hundred pound, sulphur fifteen pound, and coal eighteen pound.

VI. Saltpetre one hundred pound, sulphur ten pound, and coal eight pound.

Mr. Belidor, in his Hydraulics, speaks of a composition for gun powder which is as follows, to thirty pound of saltpetre, add five pound of sulphur, with as much coal: but the proportion of the several ingredients for powder, are to be found best by experience. For tho’ there has been so much practice in making powder, there has not yet been ascertained a standing proportion of the nitre, sulphur, and coal; but it is hoped that in time this great and noble invention will be much improved, and that the different, and best quantity of every ingredient, will be determined. At the powder mills they generally allow for wasting, in making up, one pound and a half in a hundred. And their mixture for a hundred weight of good powder is thus: To seventy-six pound and a half of saltpetre, well refined and dry’d, twelve pound and a half of coal, and as much sulphur, all which added together makes one hundred one pound and a half, which when worked up will nearly weigh one hundred. As it is most certain that gun-powder is capable of being improved, I shall not omit any particular that may be of service to such ingenious gentlemen as are willing to make experiments; for which reason we shall here insert another composition for powder, mentioned by an author on this subject, whose name I have forgot, but the composition is thus: Refined salt-petre five pounds, sulphur one pound four ounces, and charcoal seven ounces and a half.

But notwithstanding you may have a good proportion of ingredients, the powder will not always be the same, for there is a great deal depends on their being well incorporated, corned and dry’d, the method of which will be taught in the next article.

To restore damaged Gun-powder to its proper strength.

It is most certain, that, if powder be kept long in a damp place, it will become weak and moist, and great part of it will be formed into hard lumps, which is a certain sign of its being damaged. When powder is thus found, you will also see at the bottom of the barrel some saltpetre, which, by being wet, will separate from the sulphur and coal, and always fall to the bottom of the vessel wherein the powder is contained, and settle there in the form of a white downey matter; but the only method to prevent this, is to move the barrels as often as convenient, and place them on their opposite sides or ends, to which they before stood: but although ever so great care be taken of powder, and it be kept as dry as possible, length of time will greatly lessen its primitive strength.

Therefore when any of the above mentioned accidents happen to your powder, you may recover it by applying to the directions here given; for example, if you imagine that the powder has not received much damage, proceed thus. Spread it on canvas, or dry boards, and expose it to the sun, then add to it an equal quantity of good powder, and mix them well together, and, when thoroughly dry, barrel it up, and put it in a dry and proper place. But if gun-powder be quite bad, the method to restore it is as follows; first, you must know what it weighed when good; then, by weighing it again, you will find how much it has lost by the separation and evaporation of the saltpetre; then add to it as much refined saltpetre, as it has lost in weight, but as a large quantity of this would be difficult to mix, it will be best to put a proportion of nitre, to every twenty pound of powder; when done, put one of these proportions into your mealing table, and grind it therein, till you have brought it to an impalpable powder, and then searce it with a fine sieve; but if any remain in the sieve that will not pass through, return it to the table, and grind it again, till you have made it all fine enough to go through the sieve; being thus well ground and sifted, it must be made into grains in the following manner, first you must have some (copper wire sieves) made according to what size you intend the grains should be; these are called corning sieves or grainers, which being provided, fill them with the powder composition, then shake them about, and the powder will pass through the sieve formed into grains. Having thus corned your powder, set it to dry in the sun; and when quite dry, searce it with a fine hair sieve in order to separate the dust from the grains. This dust may be worked up again with another mixture; so that none of the powder will be wasted: but sometimes it may so happen, that the weight of the powder when good cannot be known; in which case add to each pound an ounce or an ounce and a half of saltpetre, according as the powder is decayed, and then grind, sift, and granulate it as before directed.

N. B. If you have a large quantity of powder, that is very bad, and quite spoiled; the only way is to extract the saltpetre from it, according to the usual manner: for powder thus circumstanced, would be very difficult to recover.

Of Silent Powder, commonly called White Powder.

It would be rather absurd for any one to imagine, that it is possible for gunpowder to have any effect without some report, when it is plain and well known, that the sound does not proceed from the powder only, but from the air being rarified by the expansion of the powder.

From whence it is evident, that any composition acting with the same explosive force as gun-powder, would certainly produce the same effect, in every respect. However as for such sort of powder I never had any proof, nor ever knew any experiment made of it, but have so little opinion of it, that I should not have given it a place in this work, had it not been treated of by some authors of note; and at the same time giving every one, who is fond of this art, an opportunity of making experiments, and of knowing every thing belong thereto.

To make Silent Powder.

For the first sort, mix two pound of borax, with four pound of gun-powder.

2d. Add half a pound of lapis-calaminaris, and half a pound of borax, to two pound of powder.

3d. To six pound of gun-powder, half a pound of calcined moles, with as much borax of Venice.

4th. To six pound and a half of saltpetre, eight pound and a half of sulphur, and half a pound of the second bark of an elder tree, burnt and ground to a powder, with two pound of common salt.

There are also many other methods of making powder silent, according to report, by using camphor or touchwood instead of charcoal, or by adding to the common powder burnt paper, hay seed, &c. When any of these ingredients are to be mixed with common powder, grind them together, and make them into grains.

To make Gun-powder of different Colours.

Notwithstanding the repeated trials and experiments made by the greatest artists, to add to the strength of gun-powder, all have proved without success, and most of them have agreed that the present powder will not admit of a fourth ingredient; therefore it is evident, that any thing being mixed with the present composition of gun-powder, would rather reduce it’s strength than add to it; consequently coloured powder must be weaker than black; so that the making of powder of different colours, is only a fancy that serves to please the curious, without any other effect.

To make Gun-powder white.

To six pound of salt-petre, add one pound of the pith of an elder tree, well dryed and pulverised, with a sufficient quantity of brimstone to make it into powder, which you will find in the composition of gun-powder, or an ounce of the salt of tartar, calcined till it comes white, and then boiled in clear water, till the water is all evaporated.

To make Powder red.

Boil in water some brasil wood or Vermillion and a pound of chopped paper; and, when boiled for some time to draw out the colour, dry and meal it with a pound of sulphur, and eight pound of saltpetre.

Or, to six pound of saltpetre, put one pound of sulphur, and half a pound of amber, and blood stone one pound.

To make Yellow Powder.

Take eight pound of saltpetre, and one pound of sulphur, to which add one pound of wild saffron, that has been boiled in aqua vitæ, and afterwards made dry and mealed.

To make Green Powder.

Boil two pound of rotten wood, with some verdegrease in aqua vitæ, then dry and pound it, and mix it with a pound of sulphur, and ten pound of salt-petre.

To make Blue Powder.

Boil some indigo in aqua vitæ, with a pound of the bark of a young linden tree, then dry and reduce it to a powder, and mix it with a pound of brimstone, and eight pound of saltpetre.

To make Pulvis Fulmanans, or Thunder in a Room.

This composition is very simple, yet has a very curious effect; it is made of three parts of saltpetre, two of salt of tartar, and one of sulphur, all ground to a fine powder, and well incorporated together. As the effect of this powder is quite different to that of gun-powder, so is there a different method of firing it, which is thus: Put about two tea spoonfulls of it into a fire-shovel, or iron ladle, and set it over a slow fire, and when it is quite hot, it will go off with a violent report. There is something surprising in the nature of this composition; for as the common powder acts every way equal, and makes the greatest noise when confined, this, on the contrary, acts only downwards, and makes the strongest report when not confined.

There is another sort of fulminating powder, called fulmanans aurum, on account of there being gold mixed in its composition, which is done by a chemical preparation; but as the preparing of the ingredients require a tedious and expensive process, I shall omit the method of doing it, and let those who chuse to make chemical experiments refer to authors on that subject, by whom they will find the manner of making this powder fully explained. It is said one grain of fulmanans aurum, when made to perfection, and held on the point of a knife, over a candle, will make a report louder than a musket.