The next process is the boring, the apparatus for which is either driven by a water wheel, steam engine, or the hand, according to the extent of the manufacturer's de mand. This operation consists in giving to the barrel its proper calibre. The boring bit is a rod of iron, somewhat longer than the barrel, one end being fitted into the socket of the crank, and the other furnished with a cylindrical plug' of tempered steel, about an inch and a half long, and having its surface cut with spiral grooves, flat at bottom, and a quarter of an inch in breadth. This form gives the bit a very strong hold of the metal, and the threads, sharp at the edges, scoop out and remove every roughness and inequality from the inside of the barrel, and render the cavity smooth and equal throughout. Several bits, each a little larger than the preceding one, are afterwards succes sively passed through the barrel in the same way, until it has acquired the intended calibre. After this the fine boring bit is introduced, being a similar rod to the former, with a square bar of tempered steel, 10 or 12 inches long at its extremity, and finely sharpened on one of its sides; on the opposite side is placed a semicircular slip of wood, of a size sufficient to fill•up with the bit the entire diame ter of the liarrel, two of its edges only acting on the tube, which passing through its whole length, and kept well oil ed, is frequently repeated, and the bore enlarged by small slips of paper plated between the wood and the bit, until the inside presents a perfectly equal and polished surface. The trueness of the bore is then proved, either by a steel or leaden plug passed through its whole length. The next step towards cempleting the barrel is the operation on its exterior surface, which in common barrels is clone by grinding on a large stone; two steel pins being inserted into the mouth and breech of the tube, and smaller than its diameter. The workman holding them in his hands, presses the barrel to the stone, which revolving on the pins, grinds off the inequalities left by the hammer ; after which it is passed to another person who files and smooths it front one end to the other. The best barrel makers do not grind but turn their barrels on a lathe, which is well calculated to insure that perfect equality of thickness on which the strength and safety of the piece so greatly depends. The filing and smoothing. is afterwards performed in the usual manner. The hnperfections to which gun barrels are lia ble, and which render them dangerous to use, and apt to burst, are the chink, crack, and flaw. The first is a small rent in the direction of the length of the barrel, the second across it, and the third is a scale or plate adhering to the barrel by a narrow base, from which it spreads out like the head of a nail from its shank, and when separated leaves a pit or hollow in the metal. Chinks or flaws are of much worse consequence than the crack in fire-arms, the expansive force of the powder being exerted more upon the circumference than the length of the barrel ; the flaw is much more frequent than the chink, the latter scarcely ever occurring but in plain barrels, formed out of a single plate of iron. The proof of gun-barrels, both musket and fowling pieces, as established by Government and the Gunmakers Company of London, is a ball that fits. the diameter of the piece, and a charge of powder of equal weight, which being fired, either bursts the barrel, or de monstrates its soundness and safety. Some gunmakers are in the habit of following this test, by a water proof, in order to ascertain if the pores of the metal continue perfectly secure. Pistol barrels are forged in one piece, two at a time, joined by their muzzles, and are bored before they are cut asunder, by which means there is not only a saving of time and labour, but a greater certainty of the bores being the same.• Rifle barrels are of modern invention : The Germans have the merit of this contrivance. The rifle barrels of Kuchanrieter senior of Ratisbon are in the greatest esteem; and so fond are the Germans of excelling in the use of the rifle, that it has become one of their principal amuse ments, in which all ranks of society frequently indulge. Every town and village has their practising ground, or butts, where small prizes are competed for with an ac curacy of aim that is truly surprising. The Americans have also, from their habits of hunting, acquired great correctness in the use of rifle guns ; and within these few years our government has introduced them into the army ; the ninety-fifth regiment being peculiarly clothed, and ar med with that weapon. The manufacture of rifles, in their first formation, is exactly similar to that of other barrels, except that their external form is generally octagonal. The process of rifling is as follows: the barrel being previously bored, and finished to a true cylindrical form, is placed on the rifling machine, an instrument formed on a plank of wood seven feet long, to which is fitted a tube about an inch in diameter, with spiral grooves deeply cut internally through its whole length, and to which is attached a circttlar plate, about five inches diameter, accurately divided in concentric circles, into from five to ten' equal parts, and supported by two rings affixed to the plank, in which it revolves; an arm connected with the di viding plate, and pierced with holes, through which a pin is passed, regulates the change of the tube in giving tilt proper number of rifles to the barrel. An iron rod with a moveable handle at one end, and a steel cutter in the other, passes through the rifling tube. This rod is covered with a core of lead one foot in length, and the barrel is firmly fixed by means of two rings on the plank, standing in a straight line to the tube. The rod is then repeatedly drawn through the whole length of the barrel, until the cutter has formed one groove to the proper depth ; the pin being shifted to another hole in the dividing plate, the operation of grooving is continued until the whole Dumber that was required is complete. The barrel is then taken out of the machine and finished. This is clone by casting on the end of a small iron rod a core of lead, which, when coated with line emery 4nd oil, is drawn for a length of time by the work man from one end of the barrel to the other, till it has ac quired a high degree of smoothness and polish. The pro cess is then complete, and the barrel is ready for the ribber and breecher, ae. The best degree of spirality is found to be half a turn in alength of three feet.
The Lock was originally a cleft piece of iron, moving on a pin fixed into the stock. The match was held in the cleft, and conveyed into the printing in the pan: A lever carried down the under part of the stock, and projecting at its ex tremity, served for a trigger. This simple contrivance was followed by the wheel-lock, so called from a small solid wheel of steel, nearly a quarter of an inch in thickness, and one and a half in diameter, cut on its edge with grooves, and notched transversely. The upper part of the circum
ference of this wheel rose up through the middle of the pan : It had an axis placed in its centre, to which a chain was attached, connecting itself to the extremity of a strong spring on the outside of the lock-plate, and the whole was fixed to the barrel by screws passing through the stock. lts application was by turning the wheel with a key, or sponger, which rolled the chain iound its axis, and drew up the spring to its full tension. By this movement, a sli der that covered the pan containing the priming, retired from over it, so as to permit the dog, which held the flint, to place itself on the edge of the wheel, which being let off by the trigger, the rapid revolutions of the wheel elicited fire front the flint, and inflamed the priming. See Fig. 8, Plate CCLXXXV. To this succeeded the &a/:lance, in which a motion was given to the dog, or cock, and a mova ble plate of steel, called the frizel, or hammer, was placed vertically above the pan to receive the action of the flint. Numerous important advantages were acquired by this im provement over the wheel-lock ; first, by securing the prim ing until the instant the piece was to be fired ; and by in creasing the quickness of its action and the lightness of its construction, &c. The great perfection to which this part if a gun has been carried within these 40 years in Britain, justly acquired the profession an acknowledged celebrity over every other nation. The important requisites in a .gun lock are, that the action of the cock be as rapid as pos sible, and that it should be so placed, that on uncovering the pan, the flint may point into the centre of the printing, and as near to it as possible, without touching it. The main-spring should have a smooth and active motion ; the bammer-spring should be light, and should give a slight re sistance to the cock on its striking the steel, which ought to move on a roller ; and the temper should not be ado hard or too soft, the one extreme being known by a roughness on its surface, and the other by the flint's making scarcely any impression on it, and producing little or no fire. The inside of the lock ought to be freed and swivelled, and the tumbler and seer of steel, and also the nails, should be tem pered.
A very great improvement in the construction of gun locks has lately been made by the Rev. Mr Forsyth, minis ter of Belhelvie, in Aberdeenshire. This ingenious gentle man contrived and made with his own hands a lock to fire without a flint, and by percussion alone to inflame certain powders. This contrivance possesses so many advantages over the present lock, (even in its most perfect state) that it will ultimately supersede it entirely. Although it is not more than five or six years since it was made public, yet both the German and Prussian gun-makers have adopted it, and there is little doubt it will become general here, so soon as his patent expires. The great advantages of this discovery are, the rapid and complete inflammation of the whole charge in the chamber of the barrel, a prevention of the loss of force through the touch-hole, perfect security against rain or damp in the prhning, no flash from the pan, and less risk of accidental discharge of the piece than when the common lock is used.
This lock is represented in Figs. I, 2, 3, 4, of Plate CCLXXXV. It consists of a hammer or dog-head II, and a magazine MN. This magazine Al N, a section of which is shown in Fig. 3. consists of a roller A, round which the magazine is movable as about an axis, one end of which is screwed into the breech of the barrel, as shown in Fig. 4. The roller is perforated through its axis by a channel in, Fig. 4. which communicates with the chamber S of the gun. On the upper side of the roller is a pan B, which communicates by a hole in its centre with the channel in, and consequently with the chamber of the piece. The printing powder, which consists of three parts of the hyper oxymuriate of potash, one part of sulphur, and one part of charcoal, is put into the cavity C of the magazine, which will hold 40 printings. The opposite cavity D contains the steel punch and sPirai spring E. \Vhen this punch is press ed down, it strikes the pan B, and is again raised from the pan by the elasticity of the spiral spring. F, P are the screws, between the points of which, and the cork fixed on the inside of the magazine, the grease for oiling the roller is contained. In order to use this lock, the magazine is brought into the position she Wrl in Fig. 1, where the cavity containing the priming powder is above the pan. A small portion of the powder therefore falls into the pan. The magazine is then turned round into the position of Fig. 2. where the steel punch is uppermost at AI. The hammer H being raised, and the trigger being pulled, it gives a blow to the steel punch, which strikes the priming powder in the pan, and inflames it by the concussion. The flame hav ing no other exit, passes along the channel in, Fig. 4. and inflames the charge. One of the great advantages of this lock is, that it may be used during rain, and the piece will go off even if the lock is immersed in a ater.
A very elegant simplification of this lock has been made, by giving the magazine MN a horizontal instead of a rota tory motion. The magazine is connected with the ham mer by a lever, so that when the hammer is raised, or the piece cocked, the lever pulls the magazine over the pan, and fills it with priming. \Vhen the hammer is let go, by pulling the trigger, the magazine is moved from the prim ing pan, and the powder is inflamed by the percussion of the extremity of the hammer. This form of the lock, how ever, is not water proof.
The Stock and Mounting of Guns has assumed a great variety of forms, and not only the figure, but the mode of holding small arms has undergone a change ; the straight stock match-lock being placed Under the right arm, the crooked short hagbut and the poit•inal on the breast, and the modern musket at the right shoulder. Guns of sport, till within these thirty years, were made very crooked in the stock, and no regard was then paid to the balance of the piece ; since that period straight stocks have been uni versally adopted, and the length of the stock has been ac commodated to the stature of the person for whom it is •made. For a view of various constructions of small arms, see Plate CCLXXXV.
Fig. 5. Represents the Indian match-lock, where Al is the match held in a tube or pair of pincers, and P the pan, which holds the priming.
Fig. 6. Represents the European match-lock, or !torque buss.
Fig. 7. Represents the rest for the matchlock. Fig. 8. Represents the wheel-lock.
Fig. 9. Represents a modern fowling-piece.
Fig. 10. Represents a modern Spanish lock.