Page:Cyclopaedia, Chambers - Volume 1.djvu/943

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GUN

( io 3 )

GUN

he firfl taught the TJfe of it to the Venetians, in the Year 1380, during the War with the Genoefc 5 and that it was firft imployed in a Place antiently called FoJJa Caudeana y new Chioggia, againft Laurence de Medicis ■ and that all Italy mads Complaints againft it, as a manifefi Contraven- tion of a fair Warfare.

But what contradicts this Account, and fhews Gun-powder of an older JEra, is, that 'Peter Jllcjfius, in his various Read- ings, mentions, that the Moors being befieged in 134.3, by Mfhonfus XI. King of Cafl'dc, difchargect" a fort of Iron Mortars upon them, which made a Noife like Thunder: which is feconded by what 2)o?i 'Pedro Biihop of Leon re- lates in his Chronicle of King Alphonfus who reduced Tole- do, vi-z. that in a Sea Combat between the King of TWBMjj and the Moorifo King otScvil, above 400 Years ago, thofe o^Tttnis had certain Iron Tuns or Barrels, wherewith they threw Thunder-bolts of Fire.

2)u Cange adds, that there is mention made of it in the Rxgiflers of the Chambers of Accounts in France as early as the Year 133S. See Cannon.

To fiiy no more, it appears that our Roger 2?acon knew of Gun-powder 1 50 Years before Schwartz, was born : That excellent Friar mentions the Compofition in exprefs Terms, in his Treatife de Nullitate Magitf, publifh'd at Oxford in i2itf. ' You may raife Thunder and Lightning at pleafure,

  • fays be, by only taking Sulphur, Nitre, and Charcoal,
  • which fingly have no Effect, but mix'd together, and

4 confined in a clofe Place, caufe- a Naife and Explofion 1 greater than that of a Clap of Thunder.'

Tl ire are divers Compofirions oi~ Gun-powder, with re- fpect to "he Proportions of the three Ingredients ; to be met with.:' iji Pyrotechnical Writers: But the Procefs is much the fame in all.

The Sulphur and Salt-peter being purified, and reduced t* Powder, are put, with the Charcoal-Duff, in a Mortar, moitien'd with Water or Spirits of Wine, or the like, and pounded 24 Hours together; taking Care to wet the Mafs from time to time, to prevent its taking Fire : Laflly, fquse- zing it through a Sieve, it is formed into little Grains, or Globules ; which being dried, the Powder is compleat t, and the leaft Spark being {truck thereon from a Steel and Flint, the whole will be immediately inflam'd, and burif out with extreme Violence.

The Erfed is not hard to account for : The Charcoal fart of the Grain whereon the Spark falls, catching Fire like Tinder, the Sulphur and Nitre are readily melted, and the former alfo breaks into Flame ; and at the fame time the contiguous Grains undergo the fame Fate. Now 'tis known that Salt-peter, when ignited, rarifies to a prodigious De- gree. See Salt-Peter, and Rarification.

Sir J, Ne-zvton reafbns thus on the Point: The Charcoal and Sulphur in Gwz-powder, eafily take fire, and kindle the Nitre ; and the Spirit of the Nitre being thereby rarified into Vapour, rufhes out with an Explofion much after the manner that the Vapour of Water rufhes out of an .^olipile ; the Sulphur alfo being volatile, is converted into Vapour, and augments the Explofion : Add that the acid Vapour of the Sulphur, namely, that which diftils under a Bell into Oil of Sulphur, entring violently into the fix'd Body of the Nitre, lets loofe the Spirit of the Nitre, and excites a grea- ter Fermentation, whereby the Heat is farther augmented, and the nVd Body of the Nitre is alfo rarified into Fume, and the Explofion thereby made more vehement and quick.

For if Salt of Tartar be mixed with Gun-powder, and that Mixture be warmed till it takes Fire, the Explofion will be more violent and quick than that of Gun-powder alone, which cannot proceed from any other Caufe than the Action of the Vapour of the Gun-powder upon the Salt of Tartar, whereby that Salt is rarified. See Pulvis Fulminans.

The Explofion of Giw-fowder arifes, therefore, from the violent Action whereby all the Mixture being quickly and vehemently heated, is rarified and converted intoFumeand Vapour ; which Vapour, by the Violence of that Action, becoming fo hot as to Jhinc, appears in the Form of Fume. See Fire.

M. dc la Hire afcribes all the Force and Effect of gun- powder, to the Spring or Elafticity of the Air, inclofed in the tcveral Grains thereof, and in the Intervals or Spaces between the Grains : The Powder being kindled, fets the Sprinas of fo many little Parcels of Air a-playing, and di- lates them all at once ; whence all the Effeft; the ^Powder it felf only ferving to light a Fire which may put the Air in Acfion- uftcr which the whole is done by the Air alone.

Gun-powder is a Commodity offuch Confequence,both inrefpea of Speculation, of War, and of Commerce; (the Consumption thereof being incredible,) that it will deferve a more particular Detail— To make Gim-powder duely, then, Regard is to be had, that the Saltpeter be pure, and in fine laroe Crylf als or Shootings : Otherwife, it is to be purified, by takinp away its fix'd or common Salt, and earthy Parts, thus : Diflbi've 10 Pound* of Nitre, in a fufficient Quantity of fair

Water, fettle, filtrate, and evaporate it in a glazed Vcffel, to the Diminution of half, or till a Pellicle appear on it : The VefTel may then be taken off from the Fire, and fet in a Cellar: In twenty-four Hours the Crytals will fhoot, which, feparate from the Liquor ■ and after the like manner may the Liquor be cryftalliz'd feveral Times, till all the Salt be drawn forth : This done, put it into a Kettle, and that on a Furnace with a moderate Fire, which gradually encreafe till it begins to fmoke, evaporate, loofe its Humidity, and grow very white : It muff be kept continually fHrring with a Ladle, for fear itfhould return to its former Figure, where- by its Greafinefs will be taken away ; after that, fo much Water is to be poured into the Kettle, as will cover the Nitre, and when 'tis diffolv'd and fedue'd to the Confiftcn- cy of a thick Liquor, it muff be ffirred with a Ladle, with- out Intermiifion, till all the Moifture is again evaporated, and it be reduced to a dry and white Meal.

The like Regard is to be had to the Sulphur, chufing that which is in huge Lumps, clear and perfectly yellow, not very hard nor compact, but porous; nor yet too much Joining ; and if when fet on the Fire, it freely burns away all, leaving little or no refident Matter, 'tis a fign of its' Goodnefs ; fo likewife if it be preiVed between two Iron Plates that are hot enough to make it run, and in the run- ning appear yellow, and that which remains of a reddifh Colour, it may be concluded to be fit for the purpofe — But, in cafe the fame be foul and impure, it may be prepared in this manner ; Melt the Sulphur in a large Iron-Ladle or Por over a very gentle Coal-fire well kindled, but not flaming ; then fcum off all that rifes on the Top, and fwims upon the Sulphur; take it prefently after from the Fire, and ftrain it through a double Linnen-Cloth, letting it pafs at leifure ; lo will it be pure, thegrofs filthy Matter remaining behind in the Cloth.

For the Charcoal, the third Ingredient, fuch fhould be chofen as is large, clear, free from Knots, well burnt, and cleaving.

There are three Kinds of 'Powder, viz. Caw2on- i Powder t Muskct-'Powder, and i Pijlol- l Pcwder, of each of thefe again there are two Sorts, & ftronger and a weaker ; all which Dif- ferences arife only from the various Proportions.

The Proportions are thus : In the ftronger Cannon~ ( Pow- der, to every hundred Pounds of Salt-Pe:er, 25 Pounds of Sulphur are generally allowed, with the lame Quantity of Charcoal ; and in the weaker Canncn-'Powder , to every hundred Pounds of Salt-Peter, 2.0 Pounds of Sulphur, and 24 of Charcoal. As for the ftronger Mmket -'Powder, an hundred Pounds of Salt-Peter require 18 Pounds of Sulpha:-, and 20 of Charcoal ; and in the weaker there go to an hun- dred Pounds of Salt-Peter, 15 of Sulphur, and iS of Char- coal. In the ftronger c Piftol- c Powder, an hundred Pounds of Salt-Peter require 12 of Sulphur, and 15 of Coal; where- as the weaker has an hundred Pounds of Salt-Peter, only 10 of Sulphur, and but 18 of Charcoal.

Other Authors prelcribe other Proportions : Semienowitz y for Mortars, directs an hundred Pounds of Salt-Peter, 25 of Sulphur, and as many of Charcoal : For great Guns, an hun- dred Pounds of Salt-Peter, i 5 of Sulphur, and 18 of Salt- Peter : For Mmkets and \Pifbols , an hundred Pounds of Salt-Peter, 8 of Sulphur, and 10 of Charcoal.

Miethius extols the Proportion of one Pound of Salt-Peter to three Ounces of Charcoal ; and two, or two and a quarter of Sulphur: than which, he affirms, no Gun-powder can poffibly be ft ronger.

He adds, that the ufual Practice of making the Gun- powder weaker for Mortars, than Guns, as in the Example above, is without any Foundation, and renders the Expence needlefly much greater: For, whereas to load a large Mor- tar, 14 Pounds of common Powder is required, and confe- quently to load it ten times 240 Pounds ; he fhews, byCal- culation, that the fame Effect would be had by 180 Pounds of the ffrong \Powder,

As to the 'Procefs of making the Gun-powder : All the Ingredients arc firll to be finely powder VI, then moiffened with fair Water, or Vinegar, or Spirit of Wine, or with Water and Spirit of Wine mixed together, or Urine, which is ufual ; afterwards all mult be well beat for the Space of 24 Hours at leaff, and then granulated, after the following manner : A Sieve is to be prepared with a Bottom of thick Parchment made full of round Holes, and the former beaten Mafs moiflen'd before-hand with 20 Ounces of Spirit of Wine, 12 of Spirit of Wine-Vinegar, 13 of Spirit of Nitre, 2 of Spirit of Sal Armoniack, and 1 Ounce o£ Camphire diffolved in Spirit of Wine, and let all thefe be mingled to- gether. Otherwife, take 40 Ounces of Brandy, and one of Camphire, and let them be mixt and diffolved tor the laid Purpofe: When the whole Compound is made up into Balls as big as Eggs, put them into the Sieve, and with them a wooden Ball ; which move up and down about the Sieve, fo that it may break the Balls of Powder, and make it pafs- thro' the little Holes in Coins.

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