Part 199

Method of making GUNPOWDER. Take nitre, sulphur, and charcoal; reduce these to a fine powder, and continue to beat them for some time in a stone mortar with a wooden pestle, wetting the mixture occasionally with water, so as to form the whole into an uniform paste, which is afterwards reduced to grains, by passing it through a sieve; and in this form, being carefully dried, it becomes the common gunpowder. For greater quantities mills are used, by means of which more work may be performed in one day than a man can do in a hundred. See MILL.

This destructive powder is composed of 75 parts nitre, 9 sulphur, and 16 of charcoal, in the 100.

The granulation of gunpowder is performed by placing the mass, while in the form of a stiff paste, in a wire sieve, covering it with a board, and agitating the whole: by this means it is cut into small grains or parts, which, when of a requisite dryness, may be rendered smooth or glossy by rolling them in a cylindrical vessel or cask. Gunpowder in this form takes fire more speedily than if it be afterward reduced to powder, as may be easily accounted for from the circumstance, that the inflamation is more speedily propagated through the interstices of the grains. But the process of granulation does itself, in all probability, weaken the gunpowder, in the same manner as it is weakened by suffering it to become damp; for in this last case, the nitre, which is the only soluble ingredient, suffers a partial solution in the water, and a separation in crystals of greater or less magnitude; and accordingly the surfaces of contact are rendered less numerous.

The detonation of gunpowder has been always an interesting problem in chemistry. Numerous theories have been offered, to account for this striking fact. But it is now very well settled, that the nitric acid is decomposed by the heat of ignition; that is oxigen, combines with the charcoal, and forms carbonic acid, while the nitrogen, or other component part, with steam from the water of crystallization, becomes disengaged in the elastic form. Berthollet found, that the elastic product, afforded by the detonation of gunpowder, consisted of two parts nitrogen gas, and one carbonic acid gas. The sudden extrication and expansion of these airs are the cause of the effects of gunpowder.

The muriat afforded by combining the oxigenized muriatic acid and potash, affords gunpowder of much greater strength than the common nitre, but too dangerous for use. For the method of making this salt, See ACID (MURIATIC, OXIGENIZED).

How to refine nitre. Put into a copper, or any other vessel, 100 weight of rough nitre, with about 14 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 filtering-bags, which must be hung on a rack, with glazed earthen pans under them, in which sticks must be 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 nitre will be quite clear and transparent; if not, it wants more refining; to effect which proceed as usual, till it is well cleansed of all its earthy parts.

How to pulverize nitre. Take a copper kettle, whose bottom must be spherical, and put into it 14lb, of refined nitre, with 2 quarts or 5 pints of clean water; then put the kettle on a slow fire; and when the nitre is dissolved, if any impurities arise, skim them off; and keep constantly stirring it with 2 large spattles 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, by which means the nitre will be prevented from sticking to the kettle. When you have pulverised a quantity of nitre, be careful to keep it in a dry place.

Different kinds of GUNPOWDER. It being proper that every one who makes use of gun-powder should know of what it is composed, we shall give a brief account of its origin and use. Gunpowder, for some time after the invention of artillery, was of a composition much weaker than what we now use, or than that ancient one mentioned by Marcus Græcus: but this, it is presumed, was owing to the weakness of their first pieces, rather than to their ignorance of a better mixture: for the first pieces of artillery were of a very clumsy, inconvenient make, being usually framed of several pieces of iron bars, fitted together lengthways, and then hooped together with iron rings; and as they were first employed in throwing stone shot of a prodigious weight, in imitation of the ancient machines, to which they succeeded, they were of an enormous bore. When Mahomed II. besieged Constantinople in the year 1453, he battered the walls with stone bullets, and his pieces were some of them of the calibre of 1200lb. but they never could be fired more than four times in the 24 hours, and sometimes they burst by the first discharge. Powder at first was not grained, but in the form of fine meal, such as it was reduced to by grinding the materials together; and it is doubtful, whether the first grain of it was intended to increase its strength, or only to render it more convenient for the filling it into small charges, and the loading of small arms, to which alone it was applied for many years, whilst meal-powder was still made use of in cannon. But at last the additional strength, which the grained powder was found to acquire from the free passage of the fire between the grains, occasioned the meal-powder to be entirely laid aside. The coal for making gunpowder is either that of willow or hazle; but the lightest kind of willow is found to be the best, well charred in the usual manner, and reduced to powder. Corned powder was in use in Germany as early as the year 1568; but it was first generally used in England in the reign of Charles I.

Government powder, Ordnance-powder, such powder, as having undergone the customary proof, is so called, and received into the public magazines.

It has been recommended by a French writer to preserve gunpowder at sea by means of boxes, which should be lined with sheets of lead. M. de Gentien, a naval officer tried the experiment by lodging a quantity of gunpowder, and parchment cartridges, in a quarter of the ship which was sheathed in this manner. After they had been stowed for a considerable time, the gunpowder and cartridges were found to have suffered little from the moisture; whilst the same quantity, when lodged in wooden cases, became nearly half rotted.

Proof of Gunpowder, first take out of the several barrels of gunpowder a measure full, of about the size of a thimble, which spread upon a sheet of fine writing paper, and then fire it, if the inflammation be very rapid, the smoke rise perpendicular, and the paper be neither burnt nor spotted, it is then to be judged good powder.

Then 2 drams of the same powder are exactly weighed, and put into an eprouvette; which if it raises a weight of 24 pounds to the height of 3¹⁄₂ inches, it may be received into the public magazine as proof.

GUN-powder prover. See EPROUVETTE.

GUNSHOT, the reach or range of a gun. The space through which a shot can be thrown.

GUNSHOT-wound. Any wound received from the discharge of cannon or fire-arms.

GUNSMITH, a man who makes fire-arms.

GUNSTICK. The rammer or stick with which the charge is driven into the gun.

GUNSTOCK. The wood to which the barrel of the gun is fixed.

GUNSTONE. Such materials, chiefly stone, as were formerly discharged from artillery.

GUR, a house or dwelling in India.

GURRIES, mud forts made in India are so called. These forts are sometimes surrounded with ditches.

GURRY, an indian term to express a certain division of time, comprehending 24 minutes; but the word among the Europeans is generally understood to mean an hour. A watch is called a gurry.

GUALIOR, a stupendous military fortification on the summit of a rocky eminence in India, south of Jumma, 28 coss, or 56 English miles, from Agra. It was once taken by a daring enterprize by Col. Popham.

GHYRETTY, cantonments seven coss (14 English miles) from Calcutta. It is a palace built by Mr. Dupleix, which the British took by force in 1797, and imprisoned the principal French colonists of Chandernagore there. This was two years before the war in Europe.

GYMNASTIC, (gymnastique, Fr.) pertaining to athletic exercises, such as leaping, wrestling, drawing the cross bow, fencing, &c. The Greeks, among whom the art originated, were accustomed to strip whenever they performed any part of it.

HABERGEON, a small coat of mail, or only sleeves and gorget of mail, formed of little iron rings or meshes linked together.

HABILIMENTS of war, in ancient statutes, signify armor, harness, utensils, or other provisions, without which it is supposed there can be no ability to maintain a war.

HABILLEMENT des troupes, Fr. properly means the regimental clothing or the uniform of soldiers. The clothing of the French army was not reduced to any regular system before the reign of Louis the 14th. The following observations relative to this important object are too appropriate, and suit all countries too well, to be left unnoticed.