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chink and flaw are of much greater importance than the barrel; one end being made to fit the than the crack, as the effort of the powder is ex- socket of the crank, and the other being furnished erted upon the circumference, and not upon the with a cylindrical plug of tempered steel, about length of the barrel. In a sword or bow, the very an inch and a half in length, and having its surreverse of this takes place; for if a crack, though face cut in the manner of a perpetual screw, the bat of a slight depth, occur in either, it will break threads being flat, about a quarter of an inch in at that place when bent but a very little; because breadth, and running with very little obliquity. the effort is made upon the fibres disposed longi. This form gives the bit a very strong hold of the tudinally; whereas, if the fault be a chink. or metal ; and the threads, being sharp at the edges, even a slight flaw, the sword or bow will not give scoop out and remove every roughness and inway. The flaw is much more frequent than the equality from the inside of the barrel, and render chink; the latter scarcely ever occurring but in the cavity smooth and equal throughout. A numbarrels forged as above, in which the fibres of the ber of bits, each a little larger than the preceding metal run longitudinally; and then only when the one, are afterwards successively passed through iron is of an inferior quality. When external and the barrel in the same way, until it has acquired superficial, they are all defects in point of neatness the intended caliber. The equality of the bore is only; but, when situated within the barrel, they so essential to the excellence of a piece, that the are of a material disadvantage, by affording a greatest accuracy in every other particular will lodgment to moisture and foulness that corrode not compensate for the want of it. Any person the iron, and thus continually enlarge the excava- who wishes to know the merit of his piece in this tion until the barrel bursts, or becomes dangerous respect, may do it with tolerable accuracy, by
means of a plug of lead, cast on a rod of iron or The barrel, when forged, is either finished in wood ; or even by a musket ball, filed so as to fit the common manner, or made to undergo the oper by the ram-rod, care being taken not to use an
the bore exactly, and pushed through the barrel ration of twisting, which is a proress employed iron ram-rod, or much force, lest the ball be fiaton those barrels that are intended to be of a superior quality and price to others. This opera- tened, and an artificial difficulty created. zion consists in heating the barrel, in portions of a
The barrel may be now considered as quite few inches at a time, to a high degree of red heat;
finished with regard to its inside: at least it has when one end of it is screwed into a vise, and into nothing more to be done to it by the maker. The the other is introduced a square piece of iron with gunsmiths, however, generally make it undergo a a handle like an augur; and, by means of these, in a condition to receive its proper form and pro
further operation of polishing; after which it is the fibres of the heated portion are twisted in a spiral direction, that is found to resist the effort portions externally, by means of the file. To do of the powder much better than a longitudinal this with accuracy, four flat sides or faces are first
formed: then eight, then sixteen, and so on, To persons unacquainted with the loss which until it is made quite round; except the reinforce iron suffers in forging, it will be a matter of sur
ed part, which in most of the modern work is leit prise that 12 pounds of iron are required to pro. forced part is certainly nore elegant than the
with eight sides. This octagonal form of the rein. duce a barrel, which, when finished, shall not weigh more than two pounds and a half. But, round one formerly in use: but it adds to the although a considerable waste is unavoidable, yet
weight of the barrel without increasing its the quantity of it depends very much upon the strength; for the effort of the powder will always quality of the iron, upon that of the coal, and upon ference, without any regard to those places that
be sustained by the thinnest part of the circumthe knowledge and dexterity of the workmen. In Spain they cannot work but with charcoal; in
are thicker than the rest. France they employ pit-coal charred, or coke; in barrel, that it should be of an equal thickness on
It is absolutely necessary to the soundness of a England they use pit-coal without being charsed, but are rery careful to have it of the purest kind, every side; or, in the language of the workmen, some sorts containing a portion of sulphur and a barrel ought to be perfectly upright. In order arsenic which render the metal altogether unmal
to arrive, as nearly as possible, to this perfect leable, or, in the language of the workmen, poison equality, the gunsmiths employ an instrument the iron.
which they call a compass. It consists of an iron A circumstance of considerable importance to
rod bent so as to form two parallel branches the excellence of a barrel is, the forging it as near
about an inch distant from each other. One of as can be to the weight it is intended to be of these branches is introduced into the barrel, and when finished, so that very little be taken away in kept closely applied to the side by means of one the boring and filing; for, as the outer surface, by other branch descends parallel to this, on the out
or more springs with which it is furnished : the having undergone the action of the hammer more immediately than any
is rendered the side, and has several screws passing through it most compact and pure, we should be careful to
with their points directed to the barrel. By remove as little of it as possible: the same thing screwing these until their points touch the surholds, though in a less degree, with rigard to that face of the barrel, and then turning the instruportion of the inside of the barrel which is to be ment round within the bore, it is seen where the cut out by the boring instrument.
metal is too thick, and how much it must be re. Pistol barrels are forged in one piece, and are
duced in order to render every part of the barrel cut asunder at the muzzles after they have been perfectly equal throughout its circumference. bored; by which there is not only a saving of To form the screw in the breech-end of the barrel, iron and of labour, but a certainty of the caliber the first tool employed is a plug of tempered steel, being perfectly the same in both.
somewhat conical, and having upon its surface The next operation consists in giving to the the threads of a male screw. This tool, which is barrel its proper caliber : this is termed boring. termed a screw-tap, being introduced into the The boring-bit is a rod of iron, somewhat longer barrel, it is turned from left to right, and back
again, until it has marked out the three or four from a bar into the size and form of nails. They tirst threads of the screw: another less conical cost about ten shillings the hundred weight, and tap is then introduced; and when this has carried twenty-eighe pounds are required to make a single on the impression of the screw as far as it is in. barrel of the ordinary size. A hoop of iron, about tended to go, a third tap is employed, which is an inch broad, and six or seven inches diameter, Dearly cylindrical, and scarcely differs from the is placed perpendicularly; and the stubs, previplug of the breech which is intended to fill the ously freed from dirt by washing, are neatly piled screw tbus formed in the barrel. The breech- in it, with their beads outermost on each side, plug has its screw formed by means of a screw- until the hoop is quite filled and wedged tight place made of tempered steel, and has several fe- with them; the whole resembling a rough circumale screws corresponding with the taps employ. lar cake of iron. This is put into the fire until ic ed to form that in the barrel. A plug of seven has acquired a white heat; when it is hammered, or eight threads is sufficiently long ; and the either by the strength of the arm, or by the force threads ougbt to be neat and sharp, so as to fill of machinery, until it coalesces, and becomes one completely the turns made in the barrel by the solid mass of iron: the hoop is then removed, and tap.' The breech-plug is afterwards case-harden- the heatings and hammerings repeated, until the et, or has its surface converted into steel, hy be- iron, by being thus wrought and kneaded, is freed ing covered over with shavings of horn, or pair- from every impurity, and rendered very tougla ings of horse-hoof, and kept red-hot in the fire and close in the grain: the workman then profor some time, after which it is plunged into ceeds to draw it out into pieces of about twentywater.
four inches in length, half an inch or more in The last operation is that of colouring the bar. breadth, and half an inch in thickness. rel, previous to which it is polished with fine These pieces, however, are not all of the same emery and oil, until it presents to the eye, through- thickness, some being more and others less than out its whole length, and in whatever direction what we have mentioned, according to the prowe observe it, a perfectly smooth, equal, and posed thickness of the barrel, and that part of it splendid surface. Formerly barrels were colour- which the piece is intended to form. One of these ed by exposing them to a degree of heat which pieces, being heated red-bot for five or six inches, produced an elegant blue tinge; but, as this ef- is turned like a corkscrew, without any other fect arises from a degree of calcination taking tools than the aavil and hammer. The remaining place upon the surface of the metal, the inside of portions are successively treated in the same man. the barrel always suffered by undergoing the ner, until the whole piece is turned into a spiral, same change. This, therefore, added to the pain- forming a tube whose diameter corresponds with ful sensation excited in the eye by looking along that of the intended barrel. Four of these are a barrel so coloured, has caused the practice of generally sufficient to form a barrel of the ordiblueing to be disused for some time past. Instead nary length, which is from thirty-two to thirtyof it, barrels are now browned, as it is termed. eight inches; and the two which form the breech, To do this, the barrel is rubbed over with aqua- or reinforced part, are considerably thicker than fortis, or spirits of salt, diluted with water, and those which constitute the fore-part, or muzzle laid by until a complete coat of rust is formed of the barrel. The work man first welds one of upon it; a little oil is then applied ; and the sur- these tubes to a part of an old barrel, which serves face, being rubbed dry, is polished by means of a as a handle. He then proceeds to unite the turns bard brush and bees-wax.
of the spiral to each other, by heating the tube When the barrels intended for a double-barrel. two or ihree inches at a time, to a bright white led piece are dressed to their proper thickness, heat, and striking the end of it several times which is generally less than for single barrels,each against the anvil in a horizontal direction, and of them is filed flat on the side where it is to join with considerable force: this is termed jumping the other, so that they may fit close together. by the barrel; and the heats given for the purpose Two corresponding notches are then made at the are called jun.ping heats. A mandril is then inmuzzle and breech of each barrel; and into these troduced into the cavity; and the heated portion are fitted two small pieces of iron, to hold them is hammered lightly, to flatten the ridges or burs more strongly together. The barrels being united raised by the jumping at the place where the by tinning the parts where they touch, the ribs spirals are joined. As soon as one piece is jumpare fitted in, and made fast by the same means. ed its whole length, another is welded to it, and These ribs are the triangular pieces of iron which treated in the same manner, until the four pieces are placed between the barrels, running on the are united; when the part of the old barrel, being upper and under sides their whole length, and no louger necessary, is cut off. The welding the serving to hold them more firmly together. The turns of the spiral is performed exactly in the under rib is a late improvement, and is found same manner as before described, and is repeated more effectually to prevent the barrels from warp- three times. The barrel is afterwards finished in ing. When the barrels are thus joined, they are the same way as a common one. Stub-iron is polished and coloured in the manner already de- also wrought into plain barrels; which, as they cribed.
require a great deal lese labour, are only half the The twisted barrels are deservedly celebrated price of the twisted ones. for their superior elegance and strength, as well The canons à rubans, or ribbon-barrels, of the as for the accuracy with which they throw either French, very much resemble the English twisted ball or shot. The iron employed in them is forme barrels. The process pursued in their formation ed of stubs, which are old horse-shoe nails pro- is considerably more operose than that just de. cured from country farriers, and from poor peo- scribed, but seems to be far from possessing any ple who gain a subsistence by picking them up advantage over it. The acknowledged superiority on the great roads leading to the metropolis. of twisted and ribbon barrels over plain ones has These are originally formed from the softest and induced some persons to counterfeit them, by toughest iron that can be had; and this is still colouring plain barrels so as to chew a spirai line farther purilied by the numerous beatings and running from one end to the other. This is done hammerings it has undergone in being reduced by winding a thread or string in a spiral direction round a plain barrel, and then wetting the string employed in proving pieces of ordnance, where, with the diluted aquartortis, or spirit of salt, so insiead of the bullet, iwo feet of clay is placed that a coat of rust may be formed where the string over the powder, by which the whole force of touches : when the acid is applied the second the explosion is exerted upon the piece.” We time over the whole barrel, the part over which entirely agree with the ingenious author of La the string was applied, by being more rusted than Chasse au Fusil, in the opinion that the proof the rest, shows a dark line winding round the he mentions would be much stronger than that barrel, and renders it, when finished, scarcely dis- which is usually employed ; so much stronger, tinguishable from a twisted or ribbon-barrel
. indeed, that we do not believe any barrel could Other barrels are, by the same means, clouded in withstand it, unless the clay were put down in an irregular manner, so as to resemble those the loosest manner possible. The hardest rocks formed of stub-iron. To prove whether or not a are burst asunder by means of dry clay strongly barrel is really what it appears to be, we need rammed over the powder that is placed at the only fix upon any part on the under side that is bottom of a cylindrical cavity made in them; and covered by the stock, and having cleared it, if we certainly cannot expect that a force sufficient necessary, with a fine file, apply a feather dipped to rend in pieces immense blocks of granite can in aqua-fortis, which in a little time will render be resisted by the comparative trifling strength the fibres of the metal distinctly visible, in what- and thickness of a gun-barrel. ever direction they run.
Causes of bursting.– It may be safely asserted, The Spanish barrels have always been held in that a good barrel very seldom bursts, unless it great esteem, as well on account of the quality of be charged too highly, or in an improper manner. the iron, which is generally considered as the best Whenever, for example, from the ball not being in Europe, as because they possess the reputation rammed home, a space is left between it and the of being forged and bored more perfectly than powder, there is a great risk of the barrel burstany others. It should be observed, however, that ing on being discharged. We say a great risk, of the Spanish barrels, those only that are made because, even under these circumstances, it in the capital are accounted truly valuable; in frequently happens that the barrel does nos consequence of which a great many have been burst. If the ball stops near to the powder, made at other places, especially at Catalonia, in a very small windage is sufficient to prevent Biscay, with the names and marks of the Madrid this accident; and it is very rare that the ball gunsmiths; they are also counterfeited at Liege, touches the barrel in every part of its circumPrague, Munichi
, &c. and a person must be a very ference, unless it has been driven in by force good judge not to be deceived by these spurious with an iron ram-rod; in which case it moulds barrels.
itself to the cavity, and blocks it up completely. Proofs of barrels.-—These differ in different coun. Should this happen, the barrel, however strong tries. The Spanish proef is a very severe one; it is, will burst, even when the space between the but, as it is made before the barrel is filed, it is ball and the powder is but very inconsiderable; not satisfactory. At the royal manufactories of and the greater the space that intervenes, the St. Etienne and Charleville, in France, there were more certainly will this event take place. Mr. inspectors appointed to see that no barrels were Robins, when speaking of this matter, says, “ A sent out of these places, whether for the king's moderate charge of powder, when it has expanduse or for public sale, without being proved. ed itself through the vacant space and reaches the The first proof was made with a ball exactly fit- ball, will, by the velocity each part has acquired, ting the caliber, and an ounce of powder. "The accumulate itself behind the ball, and will thereby second was made with the same sized ball be condensed prodigiously; whence, if the barrel and half an ounce of powder. The reason be not of an extraordinary strength in that part, given for the second proof is, that the first may it must infallibly, burst. The truth of this [ have strained the barrel so much, though have experienced in a very good Tower musquet, the injury be not visible, that it will not bear a forged of very tough iron; for, charging it with second trial with a smaller charge; and it is said twelve pennyweights of powder, and placing the there really are some of these barrels which stand ball (loosely) sixteen inches from the breech; on the first proof, and yet give way in the second. the firing of it, the part of the barrel just behind
The usual proof of the Paris barrels is a double the bullet was swelled out to double its diameter, charge of powder and shot ; that is, two or two like a blown bladder, and two large pieces of two and a half drams of powder, and two or two and inches long were blown out of it, a half ounces of shot. The English Tower proof, The same accident will often take place from and that of the Whitechapel company, incorpo- the mouth of the piece being filled with earth or rated by charter for proving of arms, are made snow, as sometimes happens when we are leaping with a ball of the caliber and a charge of powder a ditch, with the muzzle of the piece pointed for equal in weight to this ball: the proof is the wards; and if in such cases the barrel do not same for every size and species of barrel, and not burst, it is because these foreign bodies stop it up repeated.
but very loosely. For the same reason, a barrel Some gunsmiths pique themselves upon making will certainly burst, if fired when the muzzle is their barrels undergo a second proof; but it is thrust into water but a very little depth below proper to observe, that if a barrel bears any as- the surface; the resistance given to the passage of signed proof, it will sustain the same immediately the inflamed powder through the mouth of the after, with greater safety than it did at first, as piece being, in this case, much greater than that the metal, from being warmed by the first fire, afforded by the sides of the barrel. Except in the expands more readily to the force of the second circumstances mentioned, or in case of an overexplosion.
charge, it is very rare that a barrel bursts. WhenMons. de Marolles, speaking of the proofs of ever it happens independent of these, it is from a
A stronger proof than ordinary defect in the work, and that either the barrel has might be made by ramıning down at top of the been imperfectly welded, or that a deep flaw has powder six or seven inches of dry clay, in place taken place in some part of it; or, lastly, that ut a double charge of lead. This is sometimes through want of care in the boring or filing, it is
left of unequal thickness in its sides. The last de- rower part, renders the recoil much greater thars fect is the most common, especially in low-priced it would have been had the bore been perfectly barrels; and, as pieces more frequently burst cylindrical. It is an invariable law in mechanics, from it than from the other defects, it ought to that action and re-action are equal; it follows, be particularly guarded against. The elastic fluid therefore, that, the weight of the piece being the which is set loose by the inflammation of the same, the recoil will be in proportion to the powder, and which endeavours to expand itself weight of the piece; or, the lighter the piece, the equally in every direction, being repelled by the greater the recoil. stronger parts, acts with additional force against In plainer language, the impelling force of the the weaker ones, and frequently bursts its way gunpowder is the tirst and most simple cause of through them; which would not have been the the fire-arms recoiling; for this force acts equally case, had the sides been of the same thickness and on the breech of the piece and on the ball: so strength, and not afforded an unequal repercus- that, if the piece and ball were of equal weight, sion. The weakness of any part of the barrel, and other circumstances the same, the piece would occasioned by the inequality of the caliber, will recoil with the same velocity as that with which still more certainly be the cause of bursting than the ball issues out of the piece.. that produced by the filing; because the intamed For the same reason, whatever retards the exit fuid being suddenly expanded at the wider part, of the charge operates like an increase of lead, must suffer a compression before it can pass ons and by contining the force of the explosion the ward, and the whole force is then exerted against more to the barrel, produces a greater recoil : the weak place; for gunpowder acts in the radii hence partly it is, that in proportion as the barrel of a circle, and exerts the same force on every becomes foul within by repeated tiring, the recoil part of the circumference of the circle.
increases. A piece will recoil, if, from the breechThe conclusion to be drawn from all this is, plug being made too short, there remain some that a thin and light barrel, which is perfectly up- turns of the screw not filled up, these hollows, right, that is, of equal thickness in every part of wherein a part of the powder is lodged, forming its circumference, is much less liable to burst an obstacle that confines and retards the explothan one which is considerably thicker and hea- sion. A barrel mounted on a stock that is very vier, but which, from being badly filed or bored, straight will recoil more than when mounted on is left of unequal strength in its sides.
a stock that is considerably bent, as the curvature In all that we have hitherto said upon the seems to break and deaden the force of the recoil; causes of bursting, the bad quality of the iron has and sometimes also a fowling piece will recoil not been taken into account: and we do not from the shooter applying it improperly to his know any means of guarding against these defects, shoulder; for if the but is not applied closely io whether arising from the badness of metal, or the shoulder, or is applied so as to be supported the insufficiency of workmanship, except by pur- only at single point, the recoil will be much chasing from a gunsmith of established reputa- more sensibly feli than when the hollow of the tion, and giving a good price for the piece.' But but embraces the shoulder, and is firmly supportby this we do not mean to sanction the practice ed by the weight of the body. Guns are observof many of the gunsmiths in the fashion of the ed to recoil more after being fired a number of day; we are confident in our opinion, that most times than they did at the beginning. The matter of their barrels are made too thin; and it may which is left upon the inside of the barrel after fairly be doubted, whether they have at all im. the explosion, and which increases on every disproved the quality of the metal. In some experi- charge, attracts moisture very quickly; especially ments made with a barrel of the celebrated La. if the saltpetre employed in the powder was not zaro Cominazzo, and which was five feet ten well purified from the admixtures of common salt, inches in length, and extremely thin, particularly which it contains in its rough state. This moistowards the muzzle, it was observed, that the ture becomes considerable after a few discharges, barrel vibrated so much after the explosion of and, being formed into vapour by the heat this charge, as to produce a whizzing or ringing during the explosion, adds its expansive efsound that might be heard to a considerable dis- fort to that of the inflamed powder, and greatly tance from the barrel. And yet this piece, not- increases the agitation and recoil. Owing to this withstanding its extreme thinness, was fired with cause, probably, rather than to that before-menvery high charges. The iron appeared to be of tioned, arises the recoil from some turns of the an extraordinary fine quality; which goes to breech-screw not being filled up by the breechprove that the cohesion of the particless of the plug, and thereby alfording a lodgment to mois. metal is the force which resists that of the pow- ture. der; and hence great advantage might be drawn Among the variety of causes to which the exto the manufacture of barrels, from an accurate cessive recoil of pieces has been attributed, there knowledge of the force of powder, and the ve. is one which yet remains to be considered; this locity of the ball. For, these points being once is, the touch-hole's being placed at some distance determined, it might be known how strong the from the breech.plug, so that the powder, instead barrel should be; by which all unnecessary waste of being fired at its base, is fired near the centre of metal might be spared on the one hand, and all of its charge; whence, it is said, the recoil is in. danger avoided on the other. For a force equal creased, and the force of the discharge weakened, to that which impels the ball is exerted on the in. by the effort of the powder being exerted more side of the piece; and if the barrel has not suffici- upon the breech than upon the ball or shot. ent strength to resist this force, it must of neces. With this idea in view, some gunsmithis form a sity burst.
channel or groove in the breech-plug, as deep as of the recoil. The most frequent cause of excess the second or third turn of the screw; the touchin the recoil is the bore of the piece being wider hole opens into this channel, and the powder is at one place than another; for although this in- therefore fired at its very lowest part; and this, equality be so small as to be imperceptible to the they assert, increases the inflammation and the eye, the repulse which the expanding fiame meets force of the powder. That the distance of the with when passing from the wider to the nur- touch-hole froin the breech, however, has very
Lietle if any share in the increase of the recoil, we This was fired at a sheet of paper measuring shall prove in the most satisfactory manner, from twenty inches by sixteen, French measure, placed experiments made purposely to determine this at the distance of twenty-eight toises, or nearly
As to the idea that the force of the dis. forty-five ordinary paces. The only difference charge is diminished by the increase of the recoil, was, that in the first set of experiments the wadit is too absurd to require discussion : the force ding consisted of card-paper, and in the second exerted by the powder upon the breech is always of hat, both cut to fit the caliber. equal to that which it exerts upon the ball or shot; Had these trials been made with no other view O that, if there be nothing in the barrel that than to determine the degree of recoil produced retards the exit of the ball, an increase in the by the different situation of the touch-hole, there recoil will be always attended with an increase in would have been no use in marking the size of the the force of the discharge.
shot, the distance and dimensions of the mark, The following experiments were made by and the number of grains thrown into it at each Mons. Le Clerc, who was gunsmith to the late discharge. It was, however, intended to try, at king of France, and well informed upon every the same time, how far the equality of the dissubject that relates to bis profession ; they were charges could be depended upon, with regard to communicated by him to Mons. De Marolles. the number of grains that struck a given space;
These experiments were made with a barrel and we shall have occasion hereafter to make ree which was thirty french inches in length, (nearly marks upon the result of the trials in this respect. thirty-two English measure,) and weighed, to- N. B. The French foot is three quarters of an gether with the loaded plank upon which it was inch longer than the English foot, and the French tixed, twenty-eight pounds. The barrel had four inch is divided into twelve lines. touch-holes which could be stopped with screws. We have thought it better to inform the reader The charge consisted of one drachm and twelve of this, and leave the table as it is, than to make grains of powder from a royal manufactory, and any fractions in the numbers by reducing it to of one ounce eighteen grains of shot called small 4. English measure.