Cupellation

“ The enormous pressure generated by the explosion of the charge forces the projectile down the bore of the gun and out of the muzzle. The body of the projectile, made of steel or iron, being smaller in diameter than the bore, easily passes through, but the driving-band being of greater diameter, and being composed of soft copper, can only pass down the bore with the projectile [Pg 87] by flowing into the grooves, thus preventing any escape of gas, and being forced to follow their twist. ”

“ They are of crucible steel, and the breech, instead of being upon a hinge, or in the form of a block, moves round in a D-shaped socket, the escape of gas being further prevented by rings of phosphor-copper. The manner in which the ordnance of this country is constructed is sufficiently familiar to our readers. A tube of steel is encompassed by jackets of wrought-iron, and in this way the toughness of the latter is combined with the hardness of the former. All our guns, as we have said, load at the muzzle, while those of Russia, Germany, Austro-Hungary, and Turkey, are breech-loaders. ”

“ For, apart from the increase in the size and mass of the projectile and its greater initial resistance to motion, pressures tended to increase in a greater ratio than the size of the pieces themselves;205 the mass of the projectile increased as the cube, the propulsive force of the gases as the square, of the diameter of the bore; hence to attain a given velocity, the larger the bore the higher the pressure required to propel it with a given type of powder,—other things being equal. No limit, therefore, could be assigned to the strength and power required of heavy ordnance. ”

“ Feint a cut at the head or a thrust over the blade, and instead of delivering a cut or thrust, parry the thrust, and return with a half longe.
PLATE XX.
A Time Cut.
PLATE XX.—TIME CUT WHEN A MAN RAISES HIS HAND TO ATTACK.
When a man raises his hand or draws it back to lead off, hit him on the outside of the wrist and get away out of distance.
In using the stop thrusts, remises, and time thrusts, great judgment is required. They should never be attempted until the swordsman has had considerable experience. ”

“ In all modern weapons we use conical projectiles, fitted near the base with a soft copper driving-band, the diameter of which is somewhat larger than that of the bore of the gun, and cut a number of spiral grooves in the barrel. ”

“ As regards direct aim, the carriages are absolutely fixed to the cupola, which itself revolves around a vertical axis. These cupolas may be struck in three different ways: (1) at right angles, by a direct shot, and consequently with a full charge--very dangerous blows, that necessitate a great thickness of the armor plate; (2) obliquely, when the projectile, if the normal component of its real velocity is not sufficient to make it penetrate, will be deflected without doing the plate much harm; and (3) by a vertical shot that may strike the armor plate with great accuracy. ”

“ The original object of armour being to keep out projectiles, I believe we shall soon adopt that material which shows a marked superiority in this respect, and steel plates appear to me to be winning the day. If the projectiles hold together—and those of modern steel make appear to stand impact well—it stands to reason that the medium they have to pass through should, from front to rear, offer a strenuous resistance. When the face of a compound plate is pierced, the remainder is no great obstacle to an uninjured projectile having a considerable amount of unexpended energy. ”

“ For a whole week I was forced to help these savages in the work of taking all that remained of the wreck to pieces, though hundreds came from the interior, and they wrought hard, some men using even their filed teeth, to get all the iron and copper bolts, which they prized more than the cargo, sails, or spars, as they could fashion them into weapons and the heads of spears and arrows. ”

“ Slowly and laboriously the little wheels of the two brass culverins, with their clumsy stocks, studded with large nails and cramped with plates of polished brass, were put in motion, by the cannoniers whipping up the six powerful horses that drew them, and the carts containing the bullets of stone and lead, the powder, and other appurtenances for the field. ”

“ Almost the next moment, a long low growl ran muttering and rumbling far away round the horizon, from the clouds and back to them again, as if they had been some huge monster or other on the watch, with its broad green muzzle shooting quietly over us as it lay; the brig dipped her gilt figure-head abeam of us, and then showed her long red streak; the swell sinking fast, and the whole sea far and wide coming out from the sky as dark and round as the mahogany drum-head of the capstan. ”

“ Another method of measuring the quality of armour, which is largely employed upon the continent of Europe, is by the ratio, r, between the velocity requisite to perforate any given plate and that needed to pierce a plate of mild steel of the same thickness, according to the formula of Commandant Jacob de Marre, viz. v = Ae0·7·a0·75/p0·5 where e = the thickness of the plate in centimetres, a = the calibre of the projectile in centimetres, p = the weight of the projectile in kilogrammes, v = the striking velocity of the projectile in metres per second, and log A = 1·7347. ”

“ When we come to back the plates, their power to resist penetration becomes greater, and our formula changes. The Gavre formula, given above, is used to determine the velocity necessary for a projectile to pass entirely through an iron plate and its wood backing.
Compound and steel armor are said to give about 29 per cent. more resisting power than wrought iron, but in one experiment at the proving ground, at Annapolis, a compound plate gave over 50 per cent. more resisting power than wrought iron. ”

“ If the projectile used be made of the same hexagonal shape externally as the bore of the barrel internally, that is, with a mechanical fit, metals of all degrees of hardness, from lead, or lead and tin, up to hardened steel, may be employed, and slowly-igniting powder, like that of the service, may be used. ”

“ ABcF, the line passing through the highest points of the base ring and swell of the muzzle, or the muzzle-band, is called, the natural line of sight. EPcG, is the axis of the piece [Pg 48] or line of fire; the curved line, PgD, described by the projectile, is called the trajectory, and is entirely below the line of fire, in consequence of the action of the force of gravity giving the projectile a downward tendency. The point D is called the point-blank, and its distance from the mouth of the piece, the point-blank range. ”

“ If the two parties exchange a cut or a thrust at the same moment, the one who gave his cut or thrust in the third position is victorious.
When a cut or thrust is made, the one who receives it passes his sword, i. e., stick, into his left hand, and his opponent comes to inside guard.
Always spring back to the second position after delivering a cut or thrust. ”

“ GRAPE SHOT.—See the word Shot.
GRANADES.—Hand granades may be thrown to the distance of 13 fathoms. For their dimensions, see the word Shell.
GUNNERY.—By the assistance of good tables of practice, and the tables of amplitudes, sines, tangents, and secants, all the cases in [Pg 148] gunnery in a nonresisting medium may be easily solved; and perhaps the solution may be sufficiently correct for practice, if the initial velocity of the projectile be not so great as to make the air’s resistance considerable.
For the tables of ranges with ordnance, see the different natures, as Gun, Mortar, &c. ”

“ Briefly, we may note that pieces could be grouped in four classes: viz. cannons, culverins, periers, and mortars. The cannons were large in calibre and of medium length; the culverins were of great length, to give them high ranging power; the periers, or stone-throwers, were a sort of howitzer;75 and the mortars, named probably from the apothecary’s utensil to which they bore a resemblance, were squat pieces used for projecting stones or iron balls at a high elevation. ”

“ At the command of the medium, four or five men begin to play on copper gongs, while the wife of the host comes forward and receives the spear and rooster in one hand. The medium takes the head-axe, and then the two women take hold of the winnower with their free hands. Keeping time to the music, they lift it from the mortar, take one step, then stop, strike the spear and head-axe together, then step and stop again. ”

“ Every point upon the surface of a projectile in motion, whether it be a rocket, javelin, ship, bullet, arrow, or any other description of projectile, is the end of a lever, the fulcrum of which is situated in the projectile’s centre of gravity. ”

“ Cannon are made whose balls pierce through and through the wooden planks of a vessel. Immediately these planks are cased with iron. To-day's balls are resisted by the vessel's sides. The plates of iron are doubled ... and forthwith the penetrating force of the projectiles is increased; but those of the next day pierce them. Steel is made to take the place of iron: but after thousands upon thousands have been spent the projectile has always the best of it. ”

“ I will ask those practical men who are here, to remember, how, if for any purpose we desired to fit a vessel, that is to bear some two or three tons per inch water pressure, with a 20-inch cover, we should provide numerous massive bolts and nuts, how we should screw them down one after another, and with what pains we should endeavour to make the joint, and the length of time that would be consumed, even when working at our best, and undisturbed by the attack of an enemy. ”

“ Bouching a gun is fixing a pure copper vent into it; which is done by drilling a hole in the piece, where the vent is usually placed, about one inch in diameter, and screwing therein a piece of wrought copper with a vent of two-ninths of an inch through the centre of it.
Tertiating a gun is examining the thickness of metal, whether the bore is perfectly straight, the trunnions properly placed, &c. ”

“ The effects of projectiles, and particularly that of penetration, depend on the nature of the projectile, its initial velocity, and the distance of the object. The effects of the various kinds of projectiles upon iron and steel plates are not yet thoroughly understood, and experiments are still being made, particularly in England, to determine the best combinations of wrought and cast iron, and steel, to resist the penetration of the enormous projectiles of the present day. ”

“ In the second which had meanwhile elapsed one of the artillerymen had swung open the breech of the gun, another had taken out the now empty copper cylinder and placed it on the floor to the right of Julia, a third had lifted a new shell and with the aid of the second had run it into the breech, and a fourth had slipped in a fresh copper cylinder containing a full charge of three of the little cream-colored tape-coils. ”

“ If a siege is to be undertaken, place in each vessel with each piece of artillery its implements, ammunition, and the carriages necessary to [Pg 122] transport the whole or a part; the platforms, tools, instruments, and materials for constructing batteries; skids, rollers, scantling, and plank.
3. If a particular calibre of gun is necessary for any operation, do not place all of one kind in one vessel, to avoid being entirely deprived of them by any accident. ”

“ The laws governing the resistance of armour to perforation have been the subject of investigation for many years, and a considerable number of formulae have been put forward by means of which the thickness of armour perforable by any given projectile at any given striking velocity Laws of resistance.may be calculated. Although in some cases based on very different theoretical considerations, there is a general agreement among them as far as perforation proper is concerned, and Tresidder’s formula for the perforation of wrought iron, t 2 = wv 3/dA, may be taken as typical. ”

“ Always deliver your cuts with a true edge and with the centre of percussion, which is generally about seven or eight inches from the point. It is the most effective part of the sword to cut with, and will not jar the arm like a cut made with any other part of the blade.
Never press upon your adversary’s blade after having delivered a cut or thrust, but recover as quickly as possible to guard the return. Should he press upon yours, disengage and return as quickly as possible.
Make all your cuts with the wrist; never throw your arm out of line, but always keep it in front of you. ”

“ She was rolling her big black hull round in it as helpless as a cask; now one side, then the other, dipping gunwale to in the round swell that came heaping up level with her very rail, and went sheeting out bright through the bulwarks again; the masts jumping, clamps and boom-irons creaking on the yards, and every sail on her shaking, as her lower yard-arms took it by turns to aim at the water—you heard all the noise of it, the plunge of her flat broadside, the plash from her scuppers, the jolts of her rudder, and voices on board; and wet you may be sure she was from stem to stern. ”

“ Is the space left between the bore of a piece and its projectile, and is measured by the difference of their diameters. The objects of windage are to facilitate loading, and to diminish the danger of bursting the piece; it is rendered necessary by the mechanical impossibility of making every projectile of the proper size and shape, by the unyielding nature of the material of which large projectiles are made, by the foulness which collects in the bore after each discharge, and by the use of hot and strapped shot. ”