Give me the oyster, then-'tis well’-
He opens it, and at one sup,
Gulps the contested trifle up,
And smiling gives to each a shell.

To GULLY, v. n. run with noise.

Somerville. Corrupted from gurgle. To

GU'LLYHOLE, n. s. hole where the gutters subterraneous sewer. GUM, n. s. & v. a. Lat. gummi; Gr. коμμι. GUM MINESS, n. s. A vegetable substance, GUM'MOSITY, n. s. differing from a resin, GUM'MOUS, adj. in being more viscid GUM'MY, adj. and less friable, and generally dissolving in aqueous menstruums.Quincy. Sax. Loma; Dut. gumme. The fleshy covering that invests and contains the teeth. To close or smear with gum: guminy and gummous are applied to whatsoever consists, is productive of, or overgrown with, gum.

From gully and hole. The empty themselves in the

That for to speken of gomme, herbe or tre, Comparaison may none imaked be. Chaucer. Prologue to Legende of Good Women. The babe that milks me,

I'd pluck my nipple from his boneless gums.

How each arising alder now appears, And o'er the Po distils her gummy tears. The yawning youth, scarce half awake, essays His lazy limbs and dozy head to raise; Then rubs his gummy eyes, and scrubs his pate. Id. Her maiden train,

Id.

Who bore the vests that holy rites require, Incense, and odorous gums, and covered fire. Observations concerning English amber, and relatious about the amber of Prussia, prove that amber is not a guminous or resinous substance drawn out of trees by the sun's heat, but a natural fossil. Woodward.

Sugar and honey make windy liquors, and the elastick fermenting particles are detained by their innate gummosity. Floyer. The tendons are involved with great gumminess and collection of matter. Wiseman's Surgery.

The eyelids are apt to be gummed together with a viscuous humour. Id.

She untwists a wire, and from her
A set of teeth completely comes.
Flowers whose wild odours breathe but agonies,
And trees whose gums are poison.

gums

Swift.

Byron.

GUM is the mucilage of vegetables, and is of no particular smell or taste. It becomes viscous and tenacious when moistened with water; totally dissolves in water into a liquid, more or less glutinous in proportion to the quantity of the gum; not dissolving in vinous spirits or in oils; burning in the fire to a black coal, without melting or catching flame; suffering no dissipation in the heat of boiling water. The true gums are gum arabic, gum tragacanth, gum senega, the All others have more or less of resin in them. gum of cherry and plum trees, and such like. See CHEMISTRY. For more particular descriptions of the gums, and also of the gum-resins, see CHEMISTRY, Index.

GUM ELASTIC is treated of under the title of CAOUTCHOUC both in the article CHEMISTRY and in its alphabetical place. GUAIACUM is also separately noticed in the body of the work.

GUM, in gardening, a kind of gangrene incident to fruit-trees of the stone kind, arising from a corruption of the sap, which, by its viscidity, not being able to make its way through the fibres of the tree, is, by the protrusion of other juice, made to extravasate and ooze out upon the bark. When the distemper surrounds the branch, it admits of no remedy; but when only on one part of a bough, it should be taken off to the quick, and some cow dung clapped on the wound, covered over with a linen cloth, and tied down. M. Quintinie directs to cut off the morbid branch two or three inches below the part affected.

GUM ARABIC is the produce of a species of Mimosa. Its chief use in medicine is from its glutinous quality, which serves to incrassate and obtund thin acrid humors, and thus is useful in coughs, alvine fluxes, hoarsenesses, gripes, &c. In a dysuria the true gum arabic is more cooling than the other simple gums. One ounce of gum arabic renders a pint of water considerably glutinous: four ounces give it a thick

Browne's Vulgar Errours. Those who are come over to the royal party are supposed to be out of gun-shot. Dryden.

It is of particular esteem with the gun-smiths for stocks. Mortimer.

The timber is used for bows, pullies, screws, mills, and gun-stocks. Id. Husbandry. Burning by gun-powder frequently happens at sea. Wiseman.

Even a gun-stick flying into fame.

Id. Stuart.

For health and idleness to passion's flame Are soil and gun-powder; and some good lessons Are also learnt from Ceres and from Bacchus Without whom Venus will not long attack us. Byron. A GUN is a weapon of offence, which forcibly discharges a ball, or other hard and solid matter, through a cylindric tube, by means of inflamed gun-powder. See GUN-POWDER. The word gun now includes most species of fire-arms; pistols and mortars being almost the only ones excepted from this denomination. They are divided into great and small guns: the former including all that we also call CANNON, ORDNANCE, or ARTILLERY; the latter including MUSKETS, CARABINES, MUSQUETOONS, BLUNDERBUSSES. FOWLING-PIECES, &c. See these articles, particularly ARTILLERY and ORDNANCE.

GUNDELIA, in botany, a genus of the polygamia segregata order, and syngenesia class of plants; natural order forty-ninth, compositæ: CAL. none: florets tubular and hermaphrodite: the receptacle bristly, with scarcely any pappus. Species one only; an American plant.

GUNDWANAHI, or GOANDWANAH, an extensive province of Hindostan, stretching from 19° to 25° of N. lat. On the north it is bounded by Allahabad and Bahar, and on the south by Orissa and the river Godavery. To the east it has parts of Orissa, Bengal, and Bahar, and to the west Malwah, Berar, and Allahabad. Its length may be estimated at 400 miles, by about 180 in breadth. It is divided into four districts, Gurrah-Mundela, Choteesgur, Nagpore, and Chandah. Its principal towns are Nagpore, Gurrah, Ruttunpore, Deogur, Ryepore, Sumbhulpore, and Bustar. The greater part of the province is mountainous, woody, poor and unhealthy, but it possesses diamond mines. The more fertile portions belong to the Nagpore Mahrattas, the remainder to various chiefs of the Goands, who, although professing the Hindoo religion, eat animal food, and are in a very uncivilised state. The Mahrattas exact from them a moderate tribute. A considerable portion of it is now included in Malwah.

A GUNNER is an officer appointed to fire the guns, either by sea or land. In the Tower of London, and other garrisons, as well as in the field, this officer carries a field staff, and a large powder-horn in a string over his left shoulder. He marches by the guns; and, when there is any apprehension of danger, his field-staff is armed with a match. His business is to lay the gun, to pass, and to help to load and traverse her.

GUNNERA, in botany, a genus of the diandria order, and gynandria class of plants. The

connected with the subject of PROJECTILES, We shall refer the reader to that article: under which not only the practical part of gunnery, but whatever relates to the action of gun-powder, the velocity it communicates to bullets, the resistance which the atmosphere opposes to their motion, and the curves they describe, will be fully treated of.

GUNPOWDER is a composition of saltpetre, sulphur, and charcoal, mixed together, and usually granulated; which easily takes fire, and when fired, expands with great vehemence, by its elastic force. To this powder we owe all the action and effect of guns, ordnance, &c., so that the modern military art in a great measure depends on it.

The invention of gun-powder is usually asscribed to one Bartholdus Schwartz, a German monk, who discovered it about the year 1320; it is said to have been first used in war by the Venetians against the Genoese in the year 1380. Thevel says its inventor was one Constantine Anelzen, a mouk of Friburg. Peter Mexia says it was first used by Alphonsus XI., king of Castile, in the year 1242. Ducange adds, that there is mention made of this powder in the registers of the chambers of accounts of France, so early as the year 1338; and our countryman friar Bacon expressly mentions the composition in his treatise De Nullitate Magia, published at Oxford in the year 1216. Some indeed are of opinion, that the Arabians or the latter Greeks were the first inventors of gun-powder about the middle ages of our era; because its Arabic name is said to be expressive of its explosive quality. Considerable improvements have lately been made in the composition of gun-powder by the Chinese.

The method of making gun-powder recommendea by colonel James is: take saltpetre, snlphur, 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 a 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 gun-powder. For greater quantities mills are used, by means of which more work may be performed in one day than a man can do in 100.

This destructive powder is composed of seventy-five parts nitre, nine sulphur, and sixteen of charcoal in the 100.

To refine the saltpetre.-Put into a copper, or any other vessel, 100 cwt. of rough nitre, with about fourteen gallons of clean water, and let it boil gently for half an hour, and as it hoils 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 must be boiled again for an hour, and strained into the pans as before, and the saltpetre 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.

To pulverise the saltpetre, take a copper kettle whose bottom must be spherical, and put into it fourteen pounds 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 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 saltpetre, be careful to keep it in a dry place.

As we have not noticed the method of making charcoal in quantities, under that head, we may here subjoin a few remarks on that important constituent of gunpowder. Common charcoal contains only sixty-four parts of diamond, or pure carbon, and thirty-six of oxygen in every 100. The charcoal of commerce is usually prepared from young wood, which is piled up near the place where it is cut, in conical heaps covered with earth, and burnt with the least possible access of air. When the fire is supposed to have penetrated to the centre of the thickest pieces, it is extinguished by entirely closing the vents. When charcoal is wanted very pure, the product of this mode of preparing it will not suffice; for the manufactory of the best gunpowder, it is distilled in iron cylinders; chemists prepare it in small quantities, in a crucible covered with sand, and, after they have thus prepared it, they pound it, and wash away the salts it contains by muriatic acid; the acid is removed by the plentiful use of water, and afterwards the charcoal is exposed to a low red heat. Pure charcoal is perfectly tasteless, and insoluble in

water.

Mr. Marshall furnishes us with a very minute account of the manufacture of charcoal. The wood having been selected, and the site or hearth being determined upon, the turf is pared off, and the sods laid on one side. The wood, about ten cords, is then laid in a ring, somewhat wider than the intended hearth; beginning on the outer circumference of the ring, with the smallest of the round wood laying the larger pieces of top wood, and the cloven roots or but-ends, towards the hearth.

With these last, some of them nearly as large as bushel blocks, they begin to make their pile; leaving a sort of chimney in the middle (a vertical aperture from a foot to eighteen inches wide); and, round this core of blocks, set up the

top wood, which has previously been cut at the time of cording, in a smooth and equable manner joining the pieces, or rather fitting them in, as close to each other as possible: placing the convex side of the logs outward; and thus forming the pile in the shape of an inverted bowl, nearly semi-globular. The pile being formed, it is tiled with sods; which are pointed, to keep in the heat the better, by filling up the seams with fine pulverised mould.

The chimney is now filled with short pieces of dry wood: near the top a live coal is put; over this one layer more of dry pieces; and, upon these, a close cap of seed is placed; nevertheless, this one coal, not larger than the first, and excluded from the open air, is sufficient to set the pile on fire. As the pieces in the chimney burn away, they are replaced with fresh ones: thus feeding the fire with fresh fuel. Closepaled hurdles are placed on the windward side of the heap, to prevent the fire from acting partially.

When the fire begins to show itself at the outward skirts of the bottom of the pile, it is known that the coal is fully burnt (or rather that the wood is sufficiently charred), which it will be, in a pile of ten cords, and in dry weather, in seven or eight days. The fire, during the whole time, is carefully kept from breaking out, by throwing mould or ashes upon the weak parts; so that, though the fire passes through every part of the wood, little or none of the matter of fire escapes.

It is a curious fact, that, notwithstanding the intense heat, no part of the tree is entirely consumed; for it is found that even the moss comes out as entire as when it went in; the only apparent change is in its being rendered friable, and of a black color. Wood that is charred shrinks considerably during the process of charring; but there is no visible derangement of parts. One of the smaller pieces, which is not broken in the drawing, appears as entire when it comes out, as when it went into the pile. The brittleness after charring, however, shows that the texture of the wood is altered, by the action of the fire.

As soon as the fire disappears, on the outside of the heap, the workmen begin to draw the coal:' an operation which is done by running a peel between the coal and the hearth; raising up the coal in such a manner as to let the mould and ashes of the sods fall through between the pieces upon the more inward parts still full of fire. If this make its appearance in any particular spot, a peel full of ashes is immediately thrown against it.

Having got sufficiently near to the fire, the coals raised by the peel are raked off, with longtoothed iron rakes: the teeth about a foot long and standing about six inches apart; the handle and head of wood, except a plate of iron on the back, with which the small coal is gathered together. No sieve, nor any rake with finer teeth than the above, is used. The coal being light is readily brought to the surface of the ashes and dirt; and, when there, is easily collected (though with a kind of slight) with the back of the rake. The side thus drawn, being rounded up and se

cured with ashes, another, the coolest part, is drawn in the same manner, till the whole packet is taken from the kiln.

Charcoal newly prepared, absorbs moisture with avidity; it also absorbs oxygen and other gases, which are condensed in its pores in quantity many times exceeding its own bulk, and are given out unaltered. Fresh charcoal allowed to cool without exposure to air, and the gas then admitted, will absorb in the following proportion: one part of charcoal will absorb 2.25 times its bulk of atmospheric air immediately, and 75 more in four or five hours; of oxygen gas about 1.8 immediately, and slowly 1 more of nitrogen gas 1.65 immediately: of nitric oxide 8.5 very slowly of hydrogen gas about 1.9 immediately: carbonic acid gas 14-3 immediately. The greater part of these gases are expelled by a heat below 212°, and a portion even by immersing the charcoal in water. These absorptions are promoted by a low temperature; but, at an elevated temperature, charcoal has such an affinity for oxygen, that it will abstract it from almost all its combinations. Hence its utility in reviving metals. Fossil coal, and all kinds of bitumen, contain a large quantity of carbon: it is also contained in oils, resins, sugar, and animal substances.

Charcoal is one of the most unchangeable substances; if the access of air be prevented, the most intense heats have no other effect than that just mentioned of hardening it, and renderng its color a deeper black. Insoluble in water, and incapable of putrefaction, it undergoes no change by mere exposure or age; and stakes and other materials of wood which have been charred, or superficially converted into charcoal, have been preserved from decay for thousands of years; the ancients availed themselves of this mode of preparing stakes which were to be driven into the ground for foundations and other purposes.

Gun-powder, says major James, for some time after the invention of artillery, was of a composition much weaker than what we now use, or 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 Mahomet II. besieged Constantinople, in the year 1453, he battered the walls with stone bullets, and his pieces were some of them of the caliber of 1200lb. but they could not be fired more than four times in the twenty-four hours, and sometimes they burst by the first discharge. And Guicciardin, in the first book of his history, informs us, that so large a portion of time between the different chargings and dischargings of one of those pieces, that the besieged had sufficient time to repair at their leisure the breaches made in their walls by the shock of such enormous stones. But as mathematical knowledge increased in Europe, that of

mechanics gradually advanced, and enabled artists, by making brass cannon of a much smaller bore for iron bullets, and a much greater charge of strong powder in proportion to their calibres, to produce a very material and important change in the construction and fabric of those original pieces. Accordingly this historian, in the same book of his history, informs us, that about 114 years after the first use made of those unwieldly pieces by the Venetians, in the war which they carried on against the Genoese in the year 1380, the French were able to procure for the invasion of Italy a great number of brass cannon mounted on carriages drawn by horses; and that these pieces could always keep pace with the army.

Gun-powder was not at first 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 graining 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 gun-powder 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.

It has been recommended by a French writer to preserve gun-powder 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 gun-powder, 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 gun powder and cartridges were found to have suffered little from the moisture; whilst the same quantity, when lodged in wooden cases, became nearly half rotted.

The proof of gun-powder, by the board of ordnance, is thus effected:-They first take out of the several barrels of gun-powder a measure full, of about the size of a thimble, which is spread upon a sheet of fine writing paper, and then fired: if the inflammation be very rapid, the smoke rises perpendicular, and if the paper be neither burnt nor spotted, it is then judged to be good powder. Then two drams of the same powder are exactly weighed, and put into an eprouvette; which, if it raises a weight of 24 lbs. to the height of three inches and a half, is received into the king's magazine as proof.

Several instruments have been invented to try the strength of gun-powder; but they have generally been complained of as inaccurate. Count Rumford, in the Philosophical Trans. vol. 71. gives an account of a method of trying the strength of it, to which the reader can also refer : but the simple method of the board of ordnance seems to answer every purpose. The following are stated to be the proportions of the different