Robert Routledge

The invention of gunpowder—or rather its use in war—appears at first sight a device little calculated to promote the general progress of mankind. But it has been pointed out by some historians that the introduction of gunpowder into Europe brought about the downfall of the feudal system with its attendant evils. In those days every man was practically a soldier: the bow or the sword he inherited from his father made him ready for the fray. But when cannons, muskets, and mines began to be used, the art of war became more difficult. The simple possession of arms did not render men soldiers, but a long special training was required. The greater cost of the new arms also contributed to change the arrangements of society. Standing armies were established, and war became the calling of only a small part of the inhabitants of a country, while the majority were left free to devote themselves to civil employments. Then the useful arts of life received more attention, inventions were multiplied, commerce began to be considered as honourable an avocation as war, letters were cultivated, and other foundations laid for modern science. If such have really been the indirect results of the invention of gunpowder, we shall hardly share the regret of the fine gentleman in “Henry IV.”:

“That it was great pity, so it was,

That villanous saltpetre should be digged

Out of the bowels of the harmless earth,

Which many a good tall fellow had destroyed

So cowardly.”

We often hear people regretting that so much attention and ingenuity as are shown by the weapons of the present day should have been expended upon implements of destruction. It would not perhaps be difficult to show that if we must have wars, the more effective the implements of destruction, the shorter and more decisive will be the struggles, and the less the total loss of life, though occurring in a shorter time. Then, again, the exasperated and savage feelings evoked by the hand-to-hand fighting under the old system have less opportunity for their exercise in modern warfare, which more resembles a game of skill. But the wise and the good have in all ages looked forward to a time when sword and spear shall be everywhere finally superseded by the ploughshare and the reaping-hook, and the whole human race shall dwell together in amity. Until that happy time arrives—

“Till the war-drum throbs no longer, and the battle flags are furl’d

In the Parliament of man, the Federation of the world—

When the common sense of most shall hold a fretful realm in awe,

And the kindly earth shall slumber, lapt in universal law,”—

we may consider that the more costly and ingenious and complicated the implements of war become, the more certain will be the extension and the permanence of civilization. The great cost of such appliances as those we are about to describe, the ingenuity needed for their contrivance, the elaborate machinery required for their production, and the skill implied in their use, are such that these weapons can never be the arms of other than wealthy and intelligent nations. We know that in ancient times opulent and civilized communities could hardly defend themselves against poor and barbarous races. But the world cannot again witness such a spectacle as Rome presented when the savage hordes of Alaric swarmed through her gates, and the mighty civilization of centuries fell under the assaults of the northern barbarians. In our day it is the poor and barbarous tribes who are everywhere at the mercy of the wealthy and cultivated nations. The present age has been so remarkably fertile in warlike inventions, that it may truthfully be said that the progress made in fire-arms and war-ships within the second half of the nineteenth century surpasses everything that had been previously accomplished from the time gunpowder came into use. Englishmen have good reason to be proud of the position taken by their country, and may feel assured that her armaments will enable her to hold her own among the most advanced nations of the world.

The subject of fire-arms embraces a very wide ground, as will appear if we consider the many different forms in which these weapons are constructed in order best to serve particular purposes. Pertaining to this subject, attention must also be directed to the modern projectiles and to the newer explosives that have largely taken the place of ordinary gunpowder. The shot gun, fowling-piece, and sporting rifle properly come under the head of fire-arms, and in the march of improvement these forms have most commonly been in advance of military muskets and rifles, the ingenuity bestowed on all their details being worthy of admiration. Nevertheless it is to the implements of war that general interest attaches; for on them depends so much the fate of battles and the destiny of nations, that whenever any country is engaged in war the question of arms becomes one of surpassing importance, enlisting the patriotic instincts of every citizen. Hence in the following pages our space will be devoted mainly to weapons of war, and more particularly to those that have been adopted by our own country.

Everyone of course is aware that guns, cannon, and gunpowder are by no means inventions of the nineteenth century; but there are fewer acquainted with the fact that rifling, breech-loading, machine guns, and revolvers were all invented and tried hundreds of years before. The devices by which some of these ideas were sought to be realised in past ages appear to us in some instances very primitive, not to say childish, when compared with modern work: but it must be remembered that nearly all the appliances required for producing such weapons had themselves to wait for their invention until the nineteenth century; such, for instance, as the steam-hammer, powerful and accurate tools, refined measuring implements, material entirely reliable such as the new steel, and also scientific investigations of all the conditions involved. The military fire-arms are of so many different forms and patterns that we can deal here with but a selection from the various services. If a rough classification had to be made, the most obvious distinction would be between the weapons the soldier carries in his hands (small-arms) and those which are mounted on some kind of carriage and discharge projectiles of much greater weight (ordnance). Ordnance again includes guns mounted on forts, carried in ships, or taken with an army into the field, in each case coming into action under different conditions. Partaking somewhat of the nature of both field-guns and of small-arms are the machine guns, of which the French mitrailleur was the first example, afterwards developing into much more effective weapons in the hands of Gatling, Gardner, Nordenfelt, Maxim, and Hotchkiss.

As much will have to be said about rifling the bores of muskets and cannon, we may here explain the nature and object of this device. The projectiles used in all guns down to comparatively recent times were almost invariably of spherical form, and could indeed scarcely be otherwise with smooth-bore weapons. As the diameter of the shot would necessarily be something less than that of the bore of the barrel, a considerable loss of power would result from the escape of the powder gases between the shot and the barrel, which escape is known as windage. Another disadvantage of the spherical projectile is that for the same weight of metal the air offers a greater resistance to its passage, and consequently checks its speed more quickly than that of any other circular form; for the air resistance is proportional to the square of the diameter, and therefore if we take a ball of 1 in. diameter and a cylinder of 1 in. in length, each having the same weight of metal, the diameter of the cylindrical shot will be a little more than four-fifths of an inch, and the air resistance to the ball will be exactly half as much again as to the cylinder, that is, in the proportion of 3 to 2. Again, the passage of the spherical shot within the barrel of the gun will not be in a straight line, but in a series of rebounds from side to side, and its direction on leaving the muzzle will depend upon which part of the bore it just before impinges on, as from that it will also take a rotatory “twist” that will in part determine its path through the air.

Now if an elongated projectile were fired from a smooth-bore gun, its course through the air would be erratic to a degree impossible to the spherical shot, for it would turn end over end with deviations that would make aiming impracticable. But if the elongated projectile is made to spin rapidly enough about its longitudinal axis, it flies through the air quite steadily, the axis of rotation remaining parallel to that of the gun throughout the whole flight. The steadiness due to rapid rotation has familiar examples in spinning tops, in gyroscopic tops, in the way arrows are feathered so that the air may cause them to revolve axially, and so on. The axial rotation of the projectile is effected by ploughing out in the cylindrical barrel of the gun a number of spiral or twisting grooves, which the projectile is compelled to follow as it travels along the barrel, either by means of corresponding protuberances formed upon its surface in the first instance, as in Jacob’s bullets, or by studs let into it, as in the studded shots and shells for ordnance which constituted at one time the regulation plan adopted by the British Government; or otherwise by making the force of the explosion expand some portion of the projectile in such a manner that this portion shall completely fill up the grooves, thus preventing windage, and causing the projectile to follow the twist of the grooves. This is the more general method, especially since the adoption of breech-loading. The Lancaster rifling, and that advocated by Whitworth, are the same in principle, but differ in appearance, from the section of the barrel being made in the one case oval, in the other hexagonal or polygonal, but with the twist necessary to produce rotation.

Incident to the discharge of all fire-arms, great and small, is a phenomenon of which we have to speak, because it is one which in the mounting of heavy ordnance especially has to be taken into account. And as it also illustrates in a very direct way one of the most general laws of nature, while people often have very vague and erroneous ideas of its cause and operation, it deserves the reader’s attention. In gunnery it is called the recoil, and is familiar to anyone who has ever fired a pistol, fowling-piece, or rifle, in the kick backwards felt at the moment of the discharge. This law is in operation whenever the condition of a body in respect to its rest or motion is changing. That is, whenever a body at rest has motion given to, or if when already moving it is made to go faster or slower, or to stop, or when the direction of the motion is changed from that in a straight line. Now although these changes or actions are frequently occurring before our eyes, the operation in them of Newton’s third law of motion does not generally present itself to common observation. This third law was stated by Sir Isaac Newton thus:—“To every action there is always an opposite and equal reaction.” Now the expanding gases due to the gunpowder explosion press the bullet forwards and the barrel (with its attachments) backwards, with the same pressure in both cases, but at the end of the bullet’s passage along the bore the same velocity is not imparted to the two bodies, because the same pressure acting for the same time on bodies of unequal mass always produces velocities that are inversely proportional to the masses. The reader should try to acquire this conception of mass, remarking that it is a something quite distinct from that of weight. A given lump of metal, for instance, would have exactly the same mass in any part of the universe, whereas its weight would depend upon its position; as, for instance, at the distance from the earth of the moon’s orbit, it would weigh only as 1
3600th part of its weight at the earth’s surface, and if it could be carried to the very centre of the earth it would there have no weight at all. Though the lump of metal will have different weights at different parts of the earth’s surface, it has been found (by experiment) that the weights of bodies at any one place are proportional to their masses. Therefore the same numbers that express the weights of bodies might also express their masses; but for certain good reasons these quantities are referred to different units. In England a piece of metal weighing 32 lbs. under standard conditions is said to have mass = 1; and so on. As with the same pressure acting for the same time, the velocities imparted are inversely proportional to the masses, it follows that the number expressing the velocity multiplied by that representing the mass in each such case of action and reaction will give the same product, or in other words the amount of motion (momentum) will be the same. This is what Newton meant by saying the reaction is equal to the action. We may now by way of illustration calculate the velocity of recoil of a rifle under conditions similar to those that might occur in practice. Let us suppose that the rifle, including the stock and all attachments, weighs 10 lbs., and that from it is fired a bullet weighing one-sixteenth of a pound, with a velocity at the muzzle of 1,200 ft. per second. To obtain the amount of motion or the momentum, we should here multiply the number expressing the mass of the bullet by 1,200, but for our present purpose the weight numbers may be used for the sake of simplicity; therefore 1
16 x 1,200 = 75 will represent (proportionately) the forward momentum of the bullet, and according to Newton’s law the backward momentum of the rifle will be, on the same scale, 75 also. We must therefore find the number which multiplied by 10 will give 75, and this obviously is 7·5. That is as much as to say that at the instant the bullet is leaving the muzzle, the rifle itself, if free to move, would be moving backward at the speed of 7½ ft. per second. Observe that this result would be the same if the rifle were fired where weight is non-existent; nor is the recoil due, as sometimes is erroneously supposed, to the resistance of the air to the passage of the bullet along the barrel, for even if the air were abolished, the recoil, so far as due to the masses and velocities, would remain the same, as indeed may be seen from the fact of our calculation taking no account of the bore of the rifle or of the shape of the bullet, circumstances of the utmost importance where atmospheric resistance is concerned.

The foregoing calculation however involves an assumption not in exact conformity with actual conditions, by taking for granted that the centre of gravity of the rifle is in the line of the axis of the barrel, while in fact this centre is almost always lower, and therefore the kick of the recoil acts in part as a turning-over push, tending to tilt up the muzzle of the gun, and for that reason the firer must hold the weapon very firmly or he will miss his aim. When such a rifle as we have supposed is fired, say from the shoulder, it would follow from the above calculation that the backward kick of the recoil is equivalent to a blow from a 10–lb. weight moving at the speed of 7½ ft. per second. This would certainly be a very uncomfortable experience, but the backward momentum must be met somehow. We have supposed that the gun is free to move, but we know the firer presses it firmly against the muscles of his shoulder, and the stock of the gun is spread out and provided with a smooth hollow heel plate, so that any pressure from it is felt as little as possible, especially as the muscle against which it is applied acts as an elastic pad. With the rifle thus firmly held we may regard the marksman and his rifle as forming only one mass, and the centre of gravity of this being now much below the axis of the barrel, the effect of the recoil tends to overthrow the man backwards; but he learns to resist this by standing firmly, so that the elasticity of his whole frame comes into play; and besides this, the mass factor of the momentum being now so large, the velocity factor becomes comparatively insignificant.

Although the momenta of gun and projectile are, according to Newton’s law, equal and opposite, the case is very different with regard to their energies, or powers of doing work, for the measure of these is jointly mass and the square of the velocity. The energy (vis viva) of a body of weight in pounds = W, moving with the velocity of v feet per second is always Wv²
64·4, that is, it will do this number of foot-lbs. units of work before it comes to rest. It would require too much space to demonstrate and fully explain here what this means, but the reader may refer to our index under the entries “Energy” and “Work,” or to any modern elementary treatise on dynamics. If the calculation be made of the energies of the ball and of the rifle due to our calculated velocities of recoil, it will be found that that of the ball is 160 times greater than that of the other, and the ball possesses this energy in a much smaller compass.

Fig. 80.—Trajectory of a Projectile.

The course or track of a projectile through the air after it leaves the gun is called the trajectory, and this has been studied both experimentally and theoretically, with interesting results. Assuming that the shot passed through empty space, or that the air offered no resistance to its passage, it would be very easy to trace the path of a projectile. Let us suppose that Fig. 80 represents a gun elevated at a high angle. The moment the projectile leaves the muzzle, gravity begins to act upon it, causing it to move vertically downwards with ever-increasing velocity until it finally reaches the ground; the onward uniform movement parallel to the axis of the piece being continued all the time. We could find the position of the projectile at the end of successive equal periods of time by drawing a straight line AC, a prolongation of the axis of the piece, or a line of the same inclination; on this we mark off equal distances representing by scale the velocity of the projectile per second, the points B, C, D, E being the positions the projectile would be in at the end of each successive second if gravity did not act. In order to bring the diagram within moderate compass, we suppose the projectile to have only the small velocity of 115 ft. per second. At the end of the first second it would be at B, but now suppose that gravity is allowed to act for one second, it would at the end of that time have fallen 16 ft. vertically below B and have arrived at b. Similarly we may set off by scale on verticals through C, D, and E distances representing 64 ft., 144 ft., and 256 ft. respectively. Because, for instance, the ball, without gravity acting, would at the end of 3 seconds be at D, where we may suppose its course arrested and gravity then allowed to act for 3 seconds to pull the ball down from its position of rest at D; at the end of this period, gravity alone acting, its position would be 144 ft. vertically below D, because gravity pulls a body that distance in 3 seconds, and the actual position 3 seconds after the ball had left the muzzle would be at d, after it had described the curved path A, b, c, d. Supposing d to be the highest point of the trajectory, another 3 seconds would bring the ball along a downward curve, and at the end of 6 seconds from the discharge it would be at a point on the same level as A. Now the complete curve would be symmetrical on each side of a vertical line through its highest point, and it would be in fact a regular parabola with its vertex at d.

The foregoing presupposes that the air offers no resistance to the passage of the projectile through it. The fact however is quite otherwise, for no sooner does the projectile begin its flight than its velocity is constantly diminished by the air’s resistance. Now this resistance is complex, depending upon a number of different conditions, the effect of which can be taken into account only by extremely complex calculations. Obviously it will vary according to the area of the section presented by the projectile to the line of its flight, and again by the shape of its front, for a pointed shot will cleave the air with less resistance than one with a flat front. Then the density of the air at the time will also enter into the calculation. The mass of the projectile and also its velocity, upon which depend its vis viva, energy, or power of overcoming resistance in doing work, will also have to be considered. Most complex of all is the law, or rather laws (i.e. relations), which connect the air resistance with the velocity; for this relation no definite expression has been found. It is a function of the velocity (known only by experiment under defined conditions), and varying with the velocity itself. Thus for velocities up to 790 ft. per second, it is a function (determined experimentally) of the second power or square of the velocity; between 790 ft. per second and 990 ft. per second the law of resistance is changed and becomes a function of the third power of the velocity; between 990 ft. and 1,120 ft. velocity the law again changes and is related to the sixth power of the velocity; between 1,120 ft. and 1,330 ft. the resistance is again related to the third power of the velocity; and with higher speeds than that last named it is again more nearly related to the square of the velocity. It will be seen that to calculate the path of a projectile is really a very difficult mathematical problem, and indeed one which can be solved only approximately when all the known data are supplied.

The air resistance to the motion of a projectile is much greater than before trial would be supposed. Let us take an experiment that has actually been recorded, in which a bullet three-quarters of an inch in diameter, weighing one-twelfth of a pound, was found to have a velocity of 1,670 ft. per second at a distance of 25 ft. from the gun, and this 50 ft. farther was reduced to 1,550 ft. per second. Now if the reader will calculate, according to the formula we have given above, the energy due to the bullet’s velocity at these points, he will find it must have done 500 foot-lbs. units of work in traversing the 50 ft., and as this could have been expended only in overcoming the resistance of the air, we learn that this last must have been equivalent to a mean or average pressure of 10 lbs. thrusting the bullet backwards.

It will be interesting to compare the difference in the trajectory of a projectile under defined conditions, worked out with the air resistance taken into account, compared with the trajectory when the air is supposed to be non-existent. We find an example of the former problem fully worked out by many elaborate mathematical formulÆ in Messrs. Lloyd and Hadcock’s treatise on Artillery. The problem is thus stated:—“An 11–in. breech-loading howitzer” (a howitzer is a piece of ordnance used for firing at high angles) “fires a 600–lb. projectile with an initial velocity of 1,120 foot-sec. at an elevation of 20°. Find the range, time of flight, and angle of descent.” We shall calculate these points on the suppositions adopted with regard to Fig. 80, and with no higher mathematics than common multiplication and division.

It will have been observed that we supposed two motions that really take place simultaneously to take place successively and independently: one in the direction of the line of fire, due to the initial velocity; the other vertically downwards, due to the action of gravity, the final result being the same. This affords an excellent illustration of another of Newton’s laws of motion, and should be considered by the reader in this connection. The law itself admits of being stated in various ways, as thus:—“Whenever a force acts on a body, it produces upon it exactly the same change of motion in its own direction, whether the body be originally at rest or in motion in any direction with any velocity whatever—whether it be at the same time acted on by other forces or not.” Or again: “When two forces act in any direction whatever on a body free to move, they impress upon it a motion which is the superposition (or compounding) of those that it would receive if each force acted separately.” The law is given also in the following form (Thomson and Tait):—“When any forces act on a body, then, whether the body be originally at rest or moving with any velocity and in any direction, each force produces in the body the exact change of motion which it would have had had it acted singly on the body originally at rest.” In all of these expressions the word “forces” is used, and a very convenient word it is, but it may be noted in passing, nothing but a word; for it stands for no real self-existing things, since, apart from observed changes of motion in bodies, forces for us have no existence. Nevertheless, it is useful for the sake of abbreviating statements about changes of motion, to regard these actions as produced by imaginary agents—imagined for the time and for this purpose, and therefore vainly to be sought for in the realm of reality.

Fig. 81.—Diagram.

In dealing with the trajectory of the howitzer’s projectile through airless space we have no concern with its diameter nor with its weight. We use the little diagram, Fig. 81, to represent the motions,—c being a horizontal line, a, a vertical one, the angle at B is therefore a right angle, and we assume that at A to be 20°. Now, the most elementary geometry teaches us that every triangle having these angles will have the lengths of its sides in the same invariable proportions one to another whatever may be the size of the triangle itself, and it has been found convenient to calculate these proportions once for all, not merely for angle 20°, but for every angle up to 90°. Besides this, distinct names have been given to the proportions of every side of the triangle to each of the other two sides. Thus in the triangle before us, if we take a, b, and c to represent the numbers expressing the lengths of the sides against which they are placed, a divided by b, that is a ÷ b, or a/b, is called the sine of angle 20°, while c/b is named the cosine of that angle, etc. These therefore are numbers which are given in mathematical tables, and we find by these that sine 20° = 0·3420201, and cosine 20° = 0·9396926, and these with the initial velocity give us all the data we require. We may first find the time the projectile would take to reach the ground level, or strictly that of the muzzle of the gun at B. Taking t to stand for this time, we know that AC = 1,120 × t, but CB will be the distance that a body would fall from rest at C by the influence of gravity in that same time, t, and it is known by experiment that this distance is 16·1 feet multiplied by the square of the time from rest in seconds. We have now therefore the length of the line CB, and put a
b = CB
AC = 16·1 × t²
1,120 × t = sine 20° = ·3420201, and dividing numerator and denominator by t and multiplying the above 3rd and 5th expressions by 1,120, we have

16·1 ×	t =	1,120 × ·3420201
		1,120 × ·3420201
and therefore	t =		= 23·7927 secs.
		16·1

Having obtained the time, it will be easy to work out the lengths b and a as 26,648 ft. and 9114·1 ft. respectively; and as c/b = cosine 20°, we have c = 26,648 × ·9396926 = 25040·8 ft., which is the range. The trajectory will be a curve (parabola) symmetrical on each side of a vertical line half-way between A and B, and the length of this line within the triangle will be equal to half of a, and in half of 23·7927 seconds the projectile, supposed to move only along the line AC, would reach the point where this vertical axis intersects AC. If during this half-time it had been falling from rest at the same intersection, it would have reached a point below by a space just one quarter of CB (the spaces fallen through being as the squares of the times), and therefore at this its highest point its distance above AB would also be one quarter the length of a = 2278·525 ft., which distance is called the height of the trajectory; and the descending curve being in every respect symmetrical to the ascending branch, the angle at which this would be inclined to AB would be 20°, but in the opposite direction to BAC, while the velocity would be the same as at A. We may now compare these results with those calculated when the air resistance is taken into account:—

	Without air	With air
	resistance.	resistance.	Difference.
Time of descent	23·7927 secs.	22·61 sec.	–1·18 sec.
Angle of descent	20°	23° 49´	+3° 49´
Velocity of descent	1120 foot-secs.	868·8 foot-secs.	–251·2 f.-s.
Range	25040·8 ft.	20,622 ft.	–4418·8 ft.
Height of trajectory	2278·5 ft.	1989 ft.	–288·5 ft.

With the air resistance the trajectory will no longer be a symmetrical curve: its highest point, instead of being on the vertical line midway between A and B, will be on one 1,050 ft. nearer to B than to A, and the descending branch will be steeper than the ascending. The total time, it will be observed, is less, although the final, and therefore the mean, velocity, is also less; but this shortening of the time is due to the trajectory itself being much less in length. The range of the projectile is decreased by 4,418 ft., or 1,473 yards, or more than four-fifths of a mile. The loss of velocity at the descent is very notable, and the reader will find it interesting to calculate the corresponding loss of energy by the formula already given.

The reader should now easily understand that the projectile from a rifle or gun discharged horizontally through airless space at the height of 16·1 ft. above a level plain would strike the ground in one second at a range or distance from the gun exactly equal to the initial velocity, or if the gun were on a tower and its axis 64·4 ft. above the plain, the range would then be 2V. It will be seen therefore that, corresponding to the range intended, there must be in general a certain inclination given to the axis of the piece in aiming, and this is done by means of the sights, one of which near the muzzle is usually fixed, while that next the breech is adjustable by sliding along an upright bar, which is graduated so that the proper elevation may be given for any required range. These graduations are made from experiments, and of course have reference only to some standard quantity and quality of ammunition and a standard of weight, shape, and material in the projectile. Sometimes large pieces of ordnance are laid by elevation in degrees, etc., marked on their mounting, the angles being taken from a table prepared for that particular gun and ammunition, from experiments at different ranges.

After these generalities about fire-arms we may enter upon certain particulars about the construction of some varieties, beginning with

THE MILITARY RIFLE.

Fig. 82.—Muzzle-loading Musket and Rifles (obsolete patterns).
A. Brown Bess and Bayonet; B. Brunswick Rifle; C. Enfield Rifle and Bayonet.

In Fig. 82 are represented the muzzle-loading musket and muzzle-loading rifles which formed the regulation weapons of the British infantry from the beginning of the century up to the year 1864. Somewhat slow in its earlier stages was the development of the modern military rifle from the old smooth bore musket with its flint-lock, which was the ordinary weapon of the British and other armies up to nearly the middle of this century. Partly, perhaps, owing to the inherent conservatism of government departments, and partly to the very serious outlay involved in arming all the troops of a nation with a new weapon, it has happened that many improvements in small arms were in use as applied to sporting guns, long before they were adopted in the regulation weapons of armies. The advance towards the modern arm of precision has been made along all the several directions that converge in the latest product, and it may be said that the most obvious of these are spiral rifling, breech-loading, and improved ammunition. The improvements in any one of these particulars would have been of little advantage unless the others had been kept in line with it. How long antiquated systems may continue in use may be illustrated by the case of the flint-lock, which was retained in the British army from the time it superseded the old match-lock, in the latter part of the seventeenth century, down to almost the middle of this present nineteenth. It is quite possible that not a few readers still in their fifties may never have seen a flint-lock outside of a museum, yet this was the firing apparatus of the weapon that used to be affectionately known to our soldiers as “Brown Bess,” and that for a century and a half continued the regulation arm of British troops helping Wellington to win his victories, and superseded by the percussion musket only in 1842. The “Brown Bess” of the earlier part of the century had a smooth-bore barrel of three-quarters of an inch diameter (0·753 inch), and 39 inches long; this musket weighed, with its bayonet, 11 lbs., 2 oz. The bullet was spherical, and made of lead, in weight a little over one ounce. The diameter of the bullet was slightly smaller than the bore of the barrel, because a closely fitting ball could not be used, on account of the great force required to push it home with a ram-rod. The bullet was therefore wrapped in loosely fitting material, called a “patch,” and this made the gun easy to load, even when the barrel was “fouled” by the solid residues that always remain after the explosion of gunpowder. “Brown Bess” was credited with a range of 200 yards, but its want of accuracy was such that the soldier was directed not to fire until he could see the whites of the enemies’ eyes. But in 1800 one or two British regiments were armed with the muzzle-loading rifle known as Baker’s, and again in 1835 these were provided with the Brunswick rifle. These regiments afterwards became known as the Rifle Brigade. The bullets in both cases were spherical, and as the earlier pattern had a seven-grooved barrel, there was so much difficulty in introducing the bullets into the muzzles that mallets had to be used. The bullet of the Brunswick rifle was encircled by a projecting band, which fitted into two rather deep grooves diametrically opposite to each other in the barrel. This bullet, wrapped in some slightly greased material, could be readily dropped into the muzzle, and rammed home without difficulty. Moreover, whereas in Baker’s rifle the grooves made only a quarter of a turn in the length of the barrel, the grooves of the Brunswick rifle made more than one complete turn. This was so much an improvement on “Brown Bess” that the effective range was more than doubled. For the rank and file of the infantry regiments the flint-lock smooth-bore musket was, however, the regulation weapon until 1842, when it was superseded by the percussion musket. The percussion-cap is now comparatively little used, as, since the introduction of cartridges containing their own means of ignition, it is rapidly becoming a thing of the past. The copper percussion-cap, in the form it still retains, was invented about 1816, and was universally adopted for sporting-guns a long time before it was used for the military weapon. In 1842 the percussion musket was definitely adopted as the weapon of the British army, but up to that date the flint-locks still continued to be made at Birmingham.

The barrel of the percussion musket then issued was shortly afterwards rifled, when about the year 1852 the MiniÉ system was adopted, and the Government awarded to M. MiniÉ, a Frenchman, the sum of £20,000 for the bullet he had invented. What the meaning of this improvement was may now be explained, and we must begin by mentioning the various forms of grooving, or, at least, such forms as found some approval during the present century, for grooved barrels had been tried long before. At first the grooves appear to have been intended merely to receive the fouling, and these were often made without any twist or spiral, but parallel to the axis of the barrel. The grooves are hollow channels of greater or less depth, and of various forms; square, triangular, rounded, or of such a form that the inner line of a section of the barrel would present the form of a ratchet wheel. The numbers of the grooves made use of have varied between two and twelve, or more, and different rates of twist, or numbers of turns of the spiral in the length of the barrel have been resorted to, these ranging from half a turn to twelve turns. The Brunswick rifle had been found wanting in accuracy, when at length in 1846 General Jacobs proposed the adoption of the conical bullet with projecting spiral ridges which fitted into grooves cut in the rifle barrel. The difficulty in using muzzle-loading rifles consisted in the force required to ram down the bullet, which had to adapt itself to the grooves, and fill them up so that the gases due to the explosion of the powder should not escape. If the bullet simply dropped into the bore of the rifle easily, it did not effectually fill the grooves, which then became channels of this windage, and if, on the other hand, the leaden bullet was made to fill the grooves from the muzzle, great force was required, and the time and effort expended in ramming the missile home, detracted enormously from the efficiency of the rifle as a military weapon. Mr. Lancaster produced rifles having a slightly oval, instead of a circular, bore, making, of course, the necessary twist within the barrel. A bullet of the corresponding section, but nearly globular, much as if the projecting belt of the Brunswick bullet had been laterally extended to its opposite poles, could be easily dropped in at the muzzle, without force being required to make it take grooves, the barrel being internally smooth throughout. It was, however, soon found that this easy-fitting ball allowed a considerable amount of windage, and the MiniÉ system was definitely adopted, in which advantage was taken of a fact observed some years before by a French artillery officer, who found that an elongated leaden bullet, if hollowed out at the base, was so expanded by the pressure of the powder gases that the material was forced into the grooves of a rifle. MiniÉ made his bullet elongated, pointed in front, and hollowed out part of its length by a conical space, the widest part of which was at the base, and was covered by a small iron cup, that, when driven inwards by the pressure of the gases, caused an expansion of the bullet by which the lead was forced into the grooves of the rifling. But the forces operating on the base of the bullet would at times cause the iron cup to cut the bullet in two, and propel the anterior portion only, leaving the base in the form of a ring clinging to the rifling. The military authorities had many comparative trials carried out between the smooth-bore percussion musket and the MiniÉ rifle. The greater accuracy of the latter may be inferred from the results of practice made by men firing at a target 6 feet high and 20 feet broad; when at 100 yards distance, 74 hits out of 100 shots were made from the musket, against 94 from the rifle; and the superiority of the latter, at longer ranges, was increasingly marked. Thus at 260, 300, and 400 yards the respective percentages of hits were for the musket 42, 16, 4½, but for the same ranges the rifle gave 80, 55, 52.

Fig. 83.—The MiniÉ Bullet.

Curiously enough, the principle of the expanding bullet had been brought forward by the late Mr. W. Greener seventeen years before the government prize was awarded to M. MiniÉ. Mr. Greener’s bullets were of an oval form, being half as long again as their diameter, with one end flattened where the lead was excavated in a narrowing hollow nearly through the bullet. In this opening was inserted the end of a tapering plug of hard metal, and when the rifle was fired this plug was driven home, and the lead thus expanded took the grooves, so preventing windage, and giving range and accuracy; while allowing the piece to be loaded with as much ease as the smooth-bore musket. The invention, though favourably reported on by the military authorities at the time, did not receive the attention it would seem to have deserved. However, in 1857, Mr. Greener’s claim of priority for the first suggestion of the expanding bullet was acknowledged by a government award of £1,000.

Fig. 84.—Greener’s Expanding Bullet.

Sir Joseph Whitworth, having been invited by the British military authorities to institute experiments with a view to producing the best type of rifle, with the help of the most perfect machinery, constructed the barrels with a polygonal bore, a plan which he had before adopted for large guns. The barrels were accurately bored out to a hexagonal section, and experiments were made to find what number of turns in the twist would give the projectile a sufficient rapidity of rotation to maintain it during its flight parallel to its axis. It was found that one turn in 20 inches was sufficient, and the projectile was made by machinery to fit accurately but easily into the rifled bore, so that it dropped into its place, and the loading could be expeditiously performed. The bullet was long, compared with the bore, which was made smaller than before, and it was found that the explosion caused it to expand sufficiently to fill up the corners of the hexagon, so that there was no loss from windage. The accuracy of aim of the Whitworth rifle was superior to that of any weapon of the kind that had, up to that time, been produced. When officially tried against the Enfield, its mean deviation at 500 yards range was only 4½ inches, while that of the Enfield at the same range was 27 inches. Mr. Whitworth had proved the advantages of using a small bore, an elongated bullet, and a sharp twist in the rifling; and it was acknowledged that as a military weapon his rifle was superior to all other arms of similar calibre that had before been produced. Some doubt appears to have been entertained, however, as to whether the mechanical perfection of the trial rifles could be maintained if they came to be manufactured on the large scale, and also as whether an adequate supply of the polygonal ammunition would be procurable when required. The Whitworth rifle was never adopted into the government service, and soon after these trials in 1857, the adoption of another type of weapon became imperative, as the results obtained by the Germans with their needle-gun, demonstrated the enormous advantages of a breech-loading rifle.

Fig. 85.—The Chassepot Rifle.—Section of the Breech.

The French then adopted the Chassepot rifle (so called after its inventor), which embodied the same principle as the needle-gun, but with improvements. This arm has a rifled barrel, with a breech mechanism of great simplicity, which is represented in section in Fig. 85. The piece marked B corresponds to what is called the “hammer” in the old lock used with percussion-caps, and the first operation in charging the rifle consists in drawing out B, as shown in the cut, until, by the spring, C, connected with the trigger, A, falling into a notch, the hammer, if we may so term it, is retained in that position. The effect of this movement is to draw out also a small rod attached to the hammer, and terminated in front by a needle, about ½ in. long, at the same time that a spiral spring surrounding the rod is compressed, the spring being fastened to the front end of the rod, and abutting against a screw-plug, which closes the hinder end of F, and permits only the rod to pass through it. The piece F, which is also movable, has projecting from its front end a little hollow cylinder, through the centre of which the needle passes, and this little cylinder has a collar, serving to retain its position, an india-rubber ring surrounding a portion of the cylinder, and forming a plug to effectually close the rear end of the barrel. It will be noticed that the cylinder is continued by a smaller projection, which forms a sheath for the point of the needle. The movable breech-piece, F, is provided with a short lever, E, by which it is worked. The second movement performed by the person who is charging the piece is to turn this lever from a horizontal to a vertical position, which thus causes the piece F to turn 90° about its axis, and then by drawing the lever towards him he removes the piece F from the end of the barrel, which, thus exposed, is ready to receive the cartridge. The cartridge contains the powder and the bullet in one case, the posterior portion containing also a charge of fulminate in the centre, and it is by the needle penetrating the case of the cartridge and detonating this fulminate that the charge is exploded. When the cartridge has been placed in the barrel, the piece F is pushed forward, the metallic collar and india-rubber ring stop up the rear of the barrel, and on turning the lever, E, into a horizontal position, the breech is entirely closed. If now the trigger be drawn, the hammer is released, and the spring carries it forward, at the same time impelling the needle through the base of the cartridge-case, where it immediately causes the explosion of the fulminate. The bullet is conical, and its base having a slight enlargement, the latter moulds itself to the grooves with which the barrel is rifled. When the piece has not to be fired immediately, the lever is not placed horizontally, but in an inclined position, in which the hammer cannot move forward, even if the trigger be drawn. The Chassepot has an effective range of 1,093 yards, and the projectile leaves the piece with a velocity of 1,345 ft. per second, the trajectory being such that at 230 yards the bullet is only 18 in. above the straight line. The piece can be charged and fired by the soldier in any position, and it was found that it could be discharged from seven to ten times per minute, even when aim was taken through the sights with which it is furnished, and fourteen or fifteen times per minute without sighting. The ordinary rifled musket, which this arm superseded, could only be fired twice in a minute, and could only be loaded when the soldier was standing up.

Other nations followed either by adopting as their infantry arm some form of breech-loader, or by converting their muzzle-loaders into breech-loaders as a temporary expedient, pending the selection of some more perfect type. When in 1864 a committee which had been appointed to investigate the question of proper arms for our infantry, recommended that that branch of the service should be supplied with breech-loaders, our Government, considering that no form of breech-loader had up to that time been invented which would unequivocally meet all the requirements of the case, wisely determined that, pending the selection of a suitable arm, the service muzzle-loaders should meanwhile be converted into breech-loaders. The problem of how this was to be done was solved by the gunmaker Snider, and in the “Converted Enfield” or “Snider” the British army was provided for a time with an arm satisfying the requirements of that period. This change of weapon was effected at a comparatively small outlay, for the conversion cost less than twenty shillings an arm. The breech action in the Snider consisted of a solid piece of metal which closed the breech end of the barrel, and, being hinged on the right-hand side parallel to the barrel, could be turned aside, making room for the insertion into the conically widened bore of a metallic cartridge case, invented by Colonel Boxer, which contained the projectile, the powder charge, and the means of ignition in itself. A short backward movement of the breech-lock caused a claw acting on the base of the spent cartridge case to withdraw it from the barrel, and then the reaction of a spring brought the breech-block back into position, after insertion of a new cartridge. This cartridge proved very effective in increasing the range and accuracy of the weapon. It should be mentioned that all the breech-loading mechanisms are provided with arrangements by which the metallic cases of the spent cartridges are automatically extracted from the barrel. The authorities having, in 1866, offered gunmakers and others handsome prizes for the production of rifles best fulfilling certain conditions, nine weapons were selected out of 104 as worthy to compete. No first prize was awarded, but the second was given to Mr. Henry, while Mr. Martini was seventh on the list. In order to obtain a weapon fulfilling all the requirements, a vast number of experiments were made by the committee appointed for that purpose, as to best construction of barrel, size of bore, system of rifling, kind of cartridge, and other particulars, and assistance was rendered by several eminent gunsmiths and engineers.

Fig. 86.—Section of Martini-Henry Lock.

After a severe competition it appeared that the best weapon would be produced by combining Henry’s system of rifling with Martini’s mechanism for breech-loading. The parts constituting the lock and the mechanism for working the breech, shown in Fig. 86, are contained in a metal case, to which is attached the woodwork of the stock, now constructed in two parts. To this case is attached the butt of the rifle by a strong metal bolt 6 in. in length, A, which is inserted through a hole in the heel-plate. The part that closes the breech—termed the “block”—is marked B. It turns loosely on a pin, C, passing through its rear end and fixed into the case at a level somewhat higher than the axis of the barrel. The end of the block is rounded off so as to form with the rear end of the case, D, which is hollowed out to receive it in a perfect knuckle joint. Let it be observed that this rounded surface, which is the width of the block, receives the whole force of the recoil, no strain being put on the pin, C, on which the block turns. In the experiments a leaden pin was substituted, and the action of the mechanism was not in the least impaired. This arrangement serves greatly to diminish the wear and the possibility of damage from the recoil. As the pin on which the block turns is slightly above the axis at the barrel, it follows that the block, when not supported, immediately drops down below the barrel. Behind the trigger-guard is a lever, E, working on a pin, F, fitted into the lower part of the case. To this lever is attached a much shorter piece called the “tumbler,” which projects into the case, G. It is this tumbler which acts as a support for the block, and raises it into its firing position or lowers it according as the lever, E, is drawn toward a firer or pushed forward. How this is accomplished will be readily understood by observing the form of the notch, H, in which the upper end of the tumbler moves. It will be noticed that the piece being in the position for firing, if the lever be pushed back, G slides away from the shallower part of the notch into the deeper, and the block accordingly falls into the position shown in the figure; and if again the lever is drawn backward, G acting on H will raise the block to its former position. The block or breech-piece is hollowed out on its upper surface, I, so as to permit the cartridge to be readily inserted into the exploding chamber, J. The centre of the block is bored out, and contains within the vital mechanism for exploding the cartridge, namely, a spiral spring, of which the little marks at K are the coils in section. These coils pass round apiece of metal called the “striker,” which is armed with a point, capable of passing through a hole in the front face of the block exactly behind the percussion-cap of the cartridge when the block is in the firing position. When the lever handle is moved forward, it causes the tumbler, which works on the same pin, to revolve, and one of its arms draws back the striker, compressing the spring in so doing, so that as the block drops down the point of the striker is drawn inwards. In this position the piece receives the cartridge into the chamber. The lever, E, being now drawn backward, the piece is forced into the notch, H, and the block is kept firmly in its place; besides this, there is a further compression of the spring by the tumbler, and in this position the spring is retained by the rest-piece, L, which is pushed into a bend in the tumbler. By pulling the trigger this piece is released, so that the tumbler can revolve freely, and relieve the pent-up spring, whose elasticity impels the striker forward, so that this enters the carriage directly. A very important and ingenious part of this arrangement is the contrivance for extracting the case of the exploded cartridge. The extractor turns on the pin, M, and has two arms pointing upwards, N, which are pressed by the rim of the cartridge pushed home into two grooves cut in the sides of the barrel. It has another arm, O, bent only slightly upwards and pointing towards the centre of the case, and forming an angle of about 80° with the above-mentioned upright arm; when, by pushing forward the lever, its short arm drops into the recess, the block, no longer supported, falls, and hits the point of the bent arm of extractor, so causing the two upright arms to extract the cartridge-case a little way.

Fig. 87.—The Martini-Henry Rifle.
A, ready for loading; B, loaded and ready for firing.

The barrel is of steel; the calibre is 0·451 in. It is rifled on Mr. Henry’s patent system. The section of the bore may be generally described as a heptagon with re-entering angles at the junctions of the planes, so that there are fourteen points of contact for the bullet, viz., one in the middle of each plane, and one at each of the re-entering angles. The twist of rifling is one turn in 22 in. The charge consists of 85 grains of powder, and a bullet weighing 480 grains, of a form designed by Mr. Henry. The cartridge is of the same general construction as the “Boxer” cartridge, used in the Snider rifle, but it is bottle-shaped, the diameter being enlarged from a short distance in rear of the bullet, in order to admit of its being made shorter, and consequently stronger, than would be otherwise possible. A wad of bees’-wax is placed between the bullet and powder, by which the barrel is lubricated at each discharge. The sword-bayonet to be used with this rifle is of a pattern proposed by Lord Elcho. It is a short sword, broad towards the point, and furnished on a portion of the back with a double row of teeth, so as to form a stout saw. It is so balanced as to form a powerful chopping implement, so that, in addition to its primary use as a bayonet, it will be useful for cutting and sawing brushwood, small trees, &c.

The following are the principal particulars of weight, dimensions, &c., of the Martini-Henry rifle:

	Without bayonet	4	ft.	1	in.
Length of rifle	With bayonet fixed	5	ft.	8	in.
	Of barrel	2	ft.	9·22	in.
Calibre				0·451	in.
Rifling	Grooves	7
	Twist	1	turn in	22	in.
Weight	Without bayonet	8	lbs.	7	oz.
	With bayonet	10	lbs.	4	oz.
Bayonet	Length	2	ft.	1½	in.
	Weight without scabbard	1	lb.	8	oz.
Charge of powder		85	grains.
Weight of bullet		480	grains.
The rifle is sighted to 1,400 yards.

As an evidence of the accuracy of fire in this rifle, it may be stated that of twenty shots fired at 1,200 yards, the mean absolute deflection of the hits from the centre of the group was 2·28 ft. The highest point in the trajectory at 500 yards is rather over 8 ft. so that the bullet would not pass over a cavalry soldier’s head within that distance. The trajectory of the Snider at the same range rises to nearly 12 ft. The bullet will pass through from thirteen to seventeen ½ in. elm planks placed 1 in. apart at 20 yards distance; the number pierced by the Snider under similar circumstances being from seven to nine. As regards rapidity of fire, twenty rounds have been fired in 53 seconds; and one arm which had been exposed to rain and water artificially applied for seven days and nights, and had during that time fired 400 rounds, was then fired, without cleaning, twenty rounds in 1 minute 3 seconds.

Rifles of the Martini-Henry and Chassepot type were soon superseded, for as early as 1876 Switzerland had armed her troops with a magazine rifle of a smaller calibre than any then in use, and this weapon was found so effective that in a few years after every European nation had followed suit, as also had the United States and Japan, each country adopting some particular pattern of a weapon with certain modifications. Of these the Mannlicher and the Mauser are much used. A magazine rifle is one that can be fired several times successively without reloading. Like revolvers, the magazine arms repeat their fire, but instead of having several distinct firing chambers, they have but one, from which the empty cartridge cases are automatically extracted by the breech mechanism, for the magazine rifle is necessarily a breech-loader. The magazine rifle carries a supply of cartridges, which one after another are brought into the firing chamber by the simple action of the breech mechanism, so that the soldier is enabled to discharge several rounds in any position without reloading. The several varieties of the magazine rifle may be classed according to the position of the magazine. This may be: First, in the stock; second, under the barrel; third, in a box under the breech; or fourth, in a box above the breech. In the first and second variety the cartridges are in line in a tube, out of which they are moved on by a spiral spring, and this was the earlier form of the weapon. The box above or below the breech is the later development, and has the advantage of holding the cartridges lying side by side, and thus in a position in which they are not so liable to injure each other as in the tubular arrangements. Then, again, the movement of the cartridge in the breechbox in arriving at the firing chamber is much less than in the linear magazines, and the centre of gravity of the whole changes but little when the supply is exhausted. With any of the varieties of magazine a suitable modification of the mechanism may be adopted, so that the weapon can at will be used as a single firing rifle, but changeable in an instant to the magazine form. Again, the box magazine may be made as a fixture on the rifle, or it may be detachable. Commissions of military authorities had for several years been deliberating upon the best models for their respective nations, while Professor Hebler was working out his researches as to the best calibre for military rifles. Hebler published a work showing the great advantages of a bore one-third less in diameter than that commonly in use, which was about 0·45 inch, as in our Martini-Henry. The small-calibre rifle shoots straighter and hits harder than the large bore one, and the recoil is less, and so is the weight of the weapon. Lead is found to be too soft a material for the bullet of the small-bore rifles, as it does not keep in the rifling, which has a sharper turn than that in the older weapon; hence the bullets are now cased in steel or nickel. These bullets have remarkable power of penetration. Some will go through a steel plate 1¼ inch thick, making a clean hole in it, and the Lebel bullet penetrates 15 inches of solid oak, at a distance of 220 yards. Such a missile would, therefore, be capable of going completely through the bodies of several men or horses.

Fig. 88.—The Mannlicher Magazine Rifle.

The Germans, about 1888, adopted a magazine rifle known as the Mauser. It had a fixed tubular magazine for eight rounds below the barrel, and a breech mechanism of the Remington-Keene type. The French followed suit with their famous Lebel gun, the construction of which was long kept secret. It also has a fixed under barrel tubular magazine, and the cartridges used with it contain smokeless powder. It is said that a new gun of practically the same pattern has been adopted by Russia, but with a detachable magazine to contain five rounds. The Russian gun will also use smokeless powder. In England, a small-bore rifle of 0·303 inches calibre is now issued to all troops. It has an under breechbox magazine, modified from the Lee rifle. The box is detachable, so that the weapon could normally be used as a single loader, and the magazine attached only when required. But the British authorities have decided that the magazine box is to be attached to the weapon by a chain. The first issue of this pattern of rifle to British soldiers took place early in 1890. The Austrians are adopting the Mannlicher pattern, in which the magazine idea is embodied in a complete and practical form. This rifle has a fixed box magazine below the breech. From this box, in which the cartridges—five in number—lie side by side, they are fed up by springs as they are disposed of by the movement of the breech mechanism. The magazine is recharged by placing in it a tin case containing five cartridges, and the case drops out when all the cartridges have been fired. In this form there is of course no necessity for providing any mechanism for holding the magazine in reserve while the rifle is used as a single loader. As to calibre, the Austrian authorities follow other countries in adopting a small bore, namely, 0·315 inch. Italy has converted her single-fire Vetterli rifle into a magazine arm, with a box something like the Mannlicher, and Belgium has adopted a gun of the same type. The rate of fire from charged magazines of such guns as the “Lee,” “Mannlicher” and “Vetterli,” worked with the right hand without bringing the piece down from the shoulder is, for all of them, about one shot per second; but the time that is required to recharge the magazines varies much according to the contrivance used. The number of rounds the magazine of a rifle is capable of containing when fully charged is from 5 to 12, or more, according to the difference of system. It is considered that in the detachable Lee or the quick recharging Mannlicher five rounds are ample for use at a critical moment.

Fig. 89.—The Magazine and Breech of the Mannlicher Rifle.

The calibre of the military rifle has been decreased with almost every new pattern adopted. Thus, while the old “Brown Bess” had a calibre of 0·75 inch, in the last issue of it the bore was reduced to 0·693 inch; the Enfield (1852) had a bore of 0·577 inch; the Martini-Henry, 0·451 inch, which, in a newer pattern adopted in 1887, was reduced to 0·400 inch; and, finally, in the Lee-Metford, the calibre is only 0·303 inch. A similar consecutive reduction of bores has taken place in the rifles adopted by other countries, and one of the latest type, issued for the use of the United States Navy, has a bore of only 0·236 inch, and it is even expected that a still smaller one will become general. The advantage of the narrow and lighter projectile is that while it has a higher initial velocity with a given charge, its flight is less checked by the resistance of the atmosphere, the section it presents being so much less. Thus the bullet of 0·236 inch diameter has a section little more than one-fourth that of the 0·45 inch bullet. The difference is well shown in the comparative heights of the trajectory (or path of the bullet) of the Martini-Henry 0·450 inch bullet, and that of the 0·303 inch Lee-Metford (the latter with cordite ammunition); for at a range of 1,000 yards the former reaches to 48 feet above the line of sight, while the latter rises to only 25 feet.

Some form of repeating or magazine rifle has now been adopted by all the most important nations of the world. The number of shots contained in the magazines varies from 5 to 12. In the British detachable box magazine there are ten charges. The calibres of the barrels range in the infantry patterns of different nations from 0·256 inch to 0·315 inch; the explosive used in every case is some kind of smokeless powder, and this, in the cartridge for the Lee-Metford, is cordite. The bullets are not made simply of lead, but of lead coated with a harder metal or alloy such as steel, cupro-nickel, nickel steel, or they consist entirely of some of these alloys.

Although the magazine rifle is now the regulation weapon of the infantry of all great armies, it is not improbable that at no distant future it maybe superseded by one in which, as in certain machine guns, the force of the recoil will be used for actuating the breech and lock movements. Many patents have already been taken out for rifles on this principle, and several patterns have actually been constructed, in which a merely momentary contact of the breech-piece with the end of the barrel is sufficient; the recoil of the barrel with the reaction of a spring performs all the requisite movements with such rapidity that an amazing speed of firing has been obtained. It is said that such an automatic gun can send forth bullets at a perfectly amazing rate. Of course the mechanism of such a gun is somewhat intricate, and it is impossible to explain its construction and action without a great number of diagrams and much description.

RIFLED CANNON.

Having briefly sketched in the foregoing section the development of the military rifle from such weapons as our own “Brown Bess,” down to the repeating or magazine rifle, we now purpose to adopt a similar course with regard to ordnance, giving also some particulars of the methods of manufacture, etc., and following in general the order of history.

Naturally there is nothing that accelerates progress in warlike inventions so much as the exigences of war itself. This is well exemplified in circumstances attending the Crimean War, which was waged in 1854 by England and France in alliance against Russia. The desire of having ships that could run the gauntlet of the heavy guns mounted on Russian forts led to the construction of La Gloire and other armour-plated vessels, as we have already seen, and a suggestion of the French Emperor, as to improving metal for guns, made to Mr. Bessemer, led incidentally but ultimately to the great revolution in the manufacture of steel, although it is true that Krupp of Essen had begun to produce small cast-steel ordnance as early as 1847. But what determined the necessity for rifled ordnance was more particularly the greater comparative effects obtained by the muzzle-loading rifles over the field artillery then in use in the several engagements that took place in the Crimea, especially in the battle of Inkerman (1854). The rifles so much surpassed in accuracy at long ranges the smooth-bore field-pieces firing spherical projectiles, that field artillery was on the point of losing its relative importance, and even in the matter of range the latter lost so much by windage that the men serving the artillery could sometimes be leisurely picked off by the rifle sharp-shooters. Inventors were soon at work on devising methods of increasing the accuracy of ordnance fire with both light and heavy pieces, and before the end of the war some cast-iron guns rifled on Lancaster’s plan had been mounted on forts and in ships, without proving very successful except in regard to increase of range when elongated pointed projectiles were used with them.

Fig. 90.—32–pounder, 1807.

Now let us see of what kind was the ordnance used for some years after the middle of the century, in order that we may be the better able to appreciate the progress that has since been made. Ordnance is, as already noticed, of several species, as guns mounted on fortresses, naval guns, siege guns, field-guns, etc., and the size of the pieces under each of those heads is distinguished sometimes in one, sometimes in another of three different ways. We may name it by the weight of the gun itself in tons or hundredweights, as “a 35–ton gun,” etc.; or by the weight of its projectile, as “a 68–pounder,” etc.; or by its calibre, that is the diameter of its bore, as “a 4–inch gun,” etc. We may take the naval guns with which Nelson won his battles (Trafalgar, 1807) as representative of all except field ordnance up to about 1856. They were all made of cast iron, threw spherical projectiles, and were very rudely mounted. The gun most commonly mounted on board our ships of war was the 32–pounder, weighing 32 cwt., shown with its carriage in Fig. 90. The carriage was of wood, and consisted of two side pieces joined back and front by two transverse pieces and carried by four low wooden wheels. The trunnions of the gun fitted into bearings at the top of the side-pieces, and were secured by iron plates that passed over them in a semi-cylindrical form and were bolted down to the wood. The position of the trunnions on the gun was always such that the breech end of the gun preponderated, being supported on an adjustable wooden wedge; and when the muzzle of the gun had to be lowered, this was done by raising the breech end with handspikes and pushing in the wedge so far as to prevent the breech from dropping down again. There was a vent or narrow passage to contain a train of powder from the touch-hole at the upper part of the breech to the rear of the charge. When the gun was fired, with its muzzle protruding a little way out of the port-hole, the recoil would trundle it inwards about its own length, when its course would be stayed by a thick rope attached to the sides of the vessel; and by other tackle it would be kept in position until loaded, when it would be allowed to roll back, or would be drawn by ropes and pulleys out to the port-hole, and by the same means such lateral inclination as might be required could be given. This last adjustment was called training the gun. A 32–pounder required the services altogether of a dozen or fourteen men, but these by virtue of constant drill would learn to handle the clumsy machine with a certain amount of expedition. If we except a notch on the highest point of the muzzle, the pieces were devoid of anything of the nature of sights, though sometimes marks were made on the adjustable wedge under the breech to correspond with certain elevations. Nor were sights required; for the mode of fighting then was to get quite close to the adversary’s ship and pour in a broadside by firing simultaneously all guns on the enemy’s side when they had been trained (by rough methods), so as to concentrate their effect as much as possible on one point of the antagonist. Nelson’s famous ship the Victory carried a few larger guns than the 32–pounders, namely, two 68–pounders, called carronades (from having first been cast at Carron in Scotland), and some 42–pounders. The 32– and 42–pounders numbered together thirty, and there were also as many 24–pounders, with forty 12–pounders. These were all simply cast of the required dimensions, and were not made with the one single improvement which after two centuries’ use of cast-iron guns had been introduced into France about fifty years before, namely, the boring of the chase out of a solid casting.

On the outbreak of the Crimean War (1854) the minds of many inventors were occupied by the problem of ordnance construction, and this also engaged the attention among others of two of the most eminent British mechanical engineers of the day. These were Sir W. Armstrong and Sir J. Whitworth, who, with others, were invited by our War Department to submit the best models of field and heavy guns their skill was severally able to produce. Two years afterward, Sir W. Armstrong had, after many experiments, completed a gun of 1·88 in. calibre. This had a forged steel barrel 6 feet in length; but it was only after eight such forgings had been bored and rejected on account of flaws revealed only by the boring that a sound barrel was at length obtained. This barrel was strengthened on the outside by jackets made from coils of wrought iron bars welded into a piece and shrunk on while hot (of which process we shall have something more to say presently); the barrel was rifled with many shallow grooves, and the pointed projectile, 3 calibres long, was made of lead, for which afterwards iron coated with lead was substituted. This gun was a breech-loader, the breech being closed by a block let into a slot after loading, and then pressed against the barrel by some turns of a screw which advanced parallel to the axis of the piece, and was made hollow for loading through, before the closing block was put in. In a trial of the various pieces ready in 1857, it was found that the Armstrong gun made as just described had an accuracy and range immensely greater than any weapon that had ever been tested, and the Government authorities approved of the system of construction, except that they preferred muzzle-loading pieces to breech-loading, as being simpler in action, more easily kept in repair, and cheaper in original cost and ammunition.

When Sir Joseph Whitworth’s gun was, in 1863, submitted to a competitive trial against the Armstrong, as to their endurance and mode of ultimate failure when fired with ever-increasing charges of powder and shot, at the forty-second round the Armstrong breech-loader split, and at the sixtieth the Armstrong muzzle-loader had one of its coils cracked; while it was not until the ninety-second round that the Whitworth gun burst violently into eleven pieces. These competing guns were 12–pounder field-guns weighing 8 cwts., and from each 2,800 regulation rounds had been fired before they were subjected to the bursting proofs. The result of these trials being that the authorities considered that steel was not then sufficiently reliable, and they decided to adopt the system of building up rifled guns with iron jackets over an inner tube of steel. Sir Joseph Whitworth made his guns entirely of steel, and they were striking examples of beautiful and accurate workmanship. His system of rifling consisted in forming the bore of the gun so that its section is a regular hexagon, and the projectile is an elongated bolt with sides exactly fitting the barrel of the gun: the projectile is, in fact, a twisted hexagonal prism. Fig. 91 shows at the left-hand side the section of the barrel, and on the right we see the form of the projectile on a smaller scale, this last representing, in fact, the exact size and shape of the bullet of the Whitworth rifle mentioned on another page. Sir Joseph’s guns were muzzle-loaders, and they were remarkable for their long range and accuracy of fire. One of these guns, with a charge of 50 lbs. of gunpowder, threw a 250–lb. shot a distance of nearly six miles, and on another occasion a 310–lb. shell was hurled through the air, and first touched the ground at a distance of more than six and a quarter miles from the gun. These distances are greater than any to which shot or shell had previously been thrown.

Fig. 91.—Whitworth Rifling and Projectile.

As the material of these Whitworth guns was very costly, and very perfect workmanship was required in the formation of the barrel and the shots, the expense attending their manufacture and use was much greater than that incurred in the case of the Armstrong guns. Sir W. Armstrong’s estimate for a 35–ton gun was £3,500, and Sir J. Whitworth’s, £6,000. The gun, as constructed at Woolwich on Mr. Fraser’s plan, was estimated to cost £2,500. The first cost of a gun is a matter for consideration, since each piece, even the strongest, is able only to fire a limited number of rounds before it becomes unsafe or useless. It appears that no cannon has yet been constructed capable of withstanding without alteration the tremendous shocks given by the explosion of the gunpowder, and these alterations, however small at any one discharge, are summed up and ultimately bring to an end what may be termed the “life of the piece.”

Fig. 92.—600–pounder Muzzle-loading Armstrong Gun.

About the year 1858 Sir William Armstrong (afterwards Lord Armstrong) established at Elswick, Newcastle-on-Tyne, a manufactory of ordnance, which has since developed into the great arsenal now so well known all over the world. Here all the resources of science have been applied to the problems of artillery, and experiments carried on with a prodigality of cost and promptness of execution impossible at a government establishment trammelled with official regulations. Here, and also at Woolwich, our national ordnance factory, guns have since always been constructed on the building-up plan advocated by Sir W. Armstrong, whose principle consists in disposing of the fibre of the iron so as best to resist the strains in the several parts of the gun. Wrought iron being fibrous in its texture has, like wood, much more strength in the direction of the grain than across it. The direction of the fibre in a bar of wrought iron is parallel to its length, and in that direction the iron is nearly twice as strong as it is transversely. A gun may give way either by the bursting of the barrel or by the blowing out of the breech. The force which tends to produce the first effect acts transversely to the axis of the gun; hence the best way to resist it is to wrap the iron round the barrel, so that the fibres of the metal encircle it like the hoops of a cask. The force which tends to blow out the breech is best resisted by disposing the fibres of the iron so as to be parallel to the axis of the gun; hence Sir W. Armstrong makes the breech-piece from a solid forging with the fibre in the required direction. But the Elswick building-up principle involves much more than the direction of the fibres of the iron, for each coil or jacket, after having its spires welded together, was bored out on a lathe, and the exterior of the part of the gun on which it was to be placed was also turned with the utmost exactness, so that when the enveloping piece was heated to a certain temperature and in this state brought into position, it would in cooling compress the parts it encircled just to that degree which careful calculations showed would best strengthen the gun without unduly straining the metal at any part. The Elswick guns being built up of several superimposed jackets of calculated lengths and thicknesses, the means was afforded of distributing the tensions throughout the whole mass of metal to the best advantage. In the simpler form, arranged by Mr. Fraser, and for the sake of economy adopted by the authorities at Woolwich in 1867, the greater part of the benefit derivable from adjustment of tension was no doubt sacrificed to cheapness of manufacture. These, and also the forms of Armstrong guns that have not yet been described, ceased to be made after 1880, by which time steel had replaced iron in every part of the construction and fittings of guns, and muzzle-loading had been definitely abandoned in favour of breech-loading.

Fig. 93.—35–ton Fraser Gun.

Now, in 1874, when the first edition of the present work was in preparation, the Fraser-Woolwich guns were in full vogue, being spoken of by the public press as the ne plus ultra of artillery construction in size, efficiency, and economy. When, accordingly, the author had been privileged to visit the arsenal and witness the production of these guns in every stage of their manufacture, he wrote a description of it which is here retained as printed at the time, seeing that it may not be without historical interest, particularly since great numbers of these guns must still be extant, mounted on our forts in various parts of the world, and seeing also that the description of the simpler formations may render more easily to be understood future references to similar operations in gun-making as have been retained in the later developments. Of course, the following description was written in the present tense, and therefore in perusing it the reader must constantly bear in mind that the guns with which our ships of war have since been equipped are in every respect entirely different from

The Fraser-Woolwich Guns, 1867–1880.

Fig. 94.—Section of 9 in. Fraser Gun.

Until the year 1867 the guns made at Woolwich were constructed according to the original plan proposed by Sir W. Armstrong, and on this system one of the large guns consisted of as many as thirteen separate pieces. These guns, though unexceptionable as to strength and efficiency, were necessarily so very costly that it became a question whether anything could be done to lessen the expense by a simpler mode of construction or by greater economy in the material. The problem was solved in the most satisfactory manner by Mr. Fraser, of the Royal Gun Factory, who proposed an important modification of the original plan, and the adoption of a kind of iron cheaper than had been previously employed, yet perfectly suited for the purpose. Mr. Fraser’s modification consisted in building up the guns from only a few coils, instead of several, the coils being longer than Sir W. Armstrong’s, and the iron coiled upon itself two or even three times: a plan which enabled him to supersede the breech-piece, formerly made in one large forging, by a piece formed of coils. In order to perceive the increased simplicity of construction introduced by Mr. Fraser, we need but glance at the section of a 9 in. gun constructed according to his system, Fig. 94, and remember that a piece of the same size made after the original plan had ten distinct parts, whereas the Fraser is seen to have but four. Compare also Figs. 92 and 93. We shall now describe the process of making the Fraser 9 in. gun. The parts of the gun as shown in the section, Fig. 94, are: 1, the steel barrel; 2, the B tube; 3, the breech-coil; 4, the cascable screw. The inner steel barrel is made from a solid cylinder of steel, which is supplied by Messrs. Firth, of Sheffield. This steel is forged from a cast block, the casting being necessary in order to obtain a uniform mass, while the subsequent forging imparts to it greater solidity and elasticity. After the cylinder has been examined, and the suitable character of the steel tested by trials with portions cut from it, the block is roughly turned and bored, and is then ready for the toughening process. This consists in heating the tube several hours to a certain temperature in an upright furnace, and then suddenly plunging it into oil, in which it is allowed to remain for a day. By this treatment the tenacity of the metal is marvellously increased. A bar of the steel 1 in. square previous to this process, if subjected to a pull equal to the weight of 13 tons, begins to stretch and will not again recover its original form when the tension is removed, and when a force of 31 tons is applied it breaks. But the forces required to affect the toughened steel in a similar manner are 31 tons and 50 tons respectively. The process, unfortunately, is not without some disadvantages, for the barrel is liable to become slightly distorted and even superficially cracked. Such cracks are removed by again turning and boring; the hardness the steel acquires by the toughening process being shown by the fact that in the first boring 8¼ in. diameter of solid steel is cut out in 56 hours, yet for this slight boring, in which merely a thin layer is peeled off, 25 hours are required; and lest there should be any fissures in the metal, which, though not visible to the eye, might make the barrel unsound, it is filled with water, which is subjected to a pressure of 8,000 lbs. per square inch. If under this enormous pressure no water is forced outwards, the barrel is considered safe. It is now ready to have the B tube shrunk on it.

The B tube, like certain other portions of these guns, is constructed from coiled iron bars, and this constitutes one great peculiarity of Sir W. Armstrong’s system. It has the immense advantage of disposing the metal so that its fibres encircle the piece, thus applying the strength of the iron in the most effective way. The bars from which the coils are prepared are made from “scrap” iron, such as old nails, horse-shoes, &c. A pile of such fragments, built up on a wooden framework, is placed in a furnace and intensely heated. When withdrawn the scraps have by semi-fusion become coherent, and under the steam hammer are soon welded into a compact mass of wrought iron, roughly shaped as a square prism. The glowing mass is now introduced into the rolling-mill, and in a few minutes it is rolled out, as if it were so much dough, into a long bar of iron. In order to form this into a coil it is placed in a very long furnace, where it can be heated its entire length. When sufficiently heated, one end of the bar is seized and attached to an iron core of the required diameter, and the core being made to revolve by a steam engine, the bar is drawn out of the furnace, winding round the core in a close spiral, so that the turns are in contact. The coil is again intensely heated, and in this condition a few strokes of the steam hammer in the direction of its axis suffice to combine the spires of the coil into one mass, thus forming a hollow cylinder.

The B tube for the 9 in. gun is formed of two double coils. When the two portions have been completely welded together under the steam hammer, the tube, after cooling, is roughly turned and bored. It is again fine bored to the required diameter, and a register of the diameter every few inches down the bore is made. These measurements are taken for the purpose of adapting most accurately the dimensions of the steel barrel to the bore of the B tube, as it is found that perfect exactness is more easily obtained in turning than in boring. The steel barrel is therefore again turned to a size slightly larger than the bore of the B tube, and is then placed muzzle end upwards, and so arranged that a stream of water, to keep it cool, shall pass into it and out again at the muzzle, by means of a syphon, while the B tube, which has been heated until it is sufficiently expanded, is passed over it and gradually cooled.

If now the B tube were allowed to cool spontaneously, its ends would, by cooling more rapidly than the central part, contract upon the steel barrel and grip it firmly at points which the subsequent cooling would tend to draw nearer together longitudinally, and thus the barrel would be subjected to injurious strains. In order to prevent this, the B tube is made to cool progressively from the breech end, by means of jets of water made to fall upon it, and gradually raised towards the muzzle end, which has in the meanwhile been prevented from shrinking by having circles of gas-flames playing upon it.

The breech-coil, or jacket, is formed of three pieces welded together. First, there is a triple coil made of bars 4 in. square, the middle one being coiled in the reverse direction to the other two. After having been intensely heated in a furnace for ten hours, a few blows on its end from a powerful steam hammer welds its coils perpendicularly, and when a solid core has been introduced, and the mass has been well hammered on the sides, it becomes a compact cylinder of wrought iron, with the fibres all running round it. When cold it is placed in the lathe, and the muzzle end is turned down, leaving a shoulder to receive the trunnion-ring. The C coil is double, welded in a similar manner to the B coil, and it has a portion turned off, so that it may be enclosed by the trunnion-ring.

The trunnion-ring is made by punching a hole in a slab of heated iron first by a small conical mandrel, and then enlarging by repeating the process with larger and larger mandrels. The iron is heated for each operation, and the trunnions are at the same time hammered on and roughly shaped—or, rather, only one has to be hammered on—for a portion of the bar which serves to hold the mass forms the other. The trunnion-ring is then bored out, and after having been heated to redness, is dropped on to the triple breech-coil which is placed muzzle end up, and the turned end of the C coil (of course, not heated) is then immediately placed within the upper part of the trunnion-ring. The latter in cooling contracts so forcibly as to bind the ends of the coils together, and the whole can thus be placed in a furnace and heated to a high temperature, so that when removed and put under the steam hammer, its parts are readily wielded into one mass. The breech-coil in this state weighs about 16 tons; but so much metal is removed by the subsequent turnings and borings, that it is reduced to nearly half that weight in the gun. It is then turned in a lathe of the most massive construction, which weighs more than 100 tons. Fig. 34, page 95, is from a drawing taken at Woolwich, and shows one of the large guns in the lathe. No one who witnesses this operation can fail to be struck with the apparent ease with which this powerful tool removes thick flakes of metal as if it were so much cheese. The projections of the trunnions prevent the part in which they are situated from being finished in this lathe, and the gun has to be placed in another machine, where the superfluous metal of the trunnion-ring is pared off by a tool moving parallel to the axis of the piece. Another machine accomplishes the turning of the trunnions, the “jacket” being made to revolve about their axis. The jacket is then accurately bored out with an enlargement or socket to receive the end of the B tube, and a hollow screw is cut at the breech end for the cascable.

The portion of the gun, consisting of the steel barrel with the B tube shrunk on it, having been placed upright with the muzzle downwards, the breech-piece, strongly heated, is brought over it by a travelling crane, and slips over the steel barrel, while the recess in it receives the end of the B tube. Cold water is forced up into the inside of the barrel in order to keep it cool. As the breech cools, which it is allowed to do spontaneously, it contracts and grips the barrel and B tube with great force. The cascable requires to be very carefully fitted. It is this piece which plays so important a part in resisting the force tending to blow out the end of the barrel. The cascable is a solid screw formed of the very best iron, and its inner end is wrought by scraping and filing, so that when screwed in there may be perfect contact between its face and the end of the steel barrel. A small annular space is left at the circumference of the inner end, communicating through a small opening with the outside. The object of this is, that in case of rupture of the steel barrel, the gases escaping through it may give timely warning of the state of the piece.

Besides minor operations, there remain the important processes of finishing the boring, and of rifling. The boring is effected in two operations, and after that the interior is gauged in every part, and “lapping” is resorted to where required, in order to obtain the perfect form. Lapping consists in wearing down the steel by friction against fine emery powder and oil, spread on a leaden surface. The piece is then ready for rifling. The machinery by which the rifling is performed cannot be surpassed for its admirable ingenuity and simplicity.

In this operation the gun is fixed horizontally, its axis coinciding with that of the bar, which carries the grooving tools. This bar is capable of two independent movements, one backwards and forwards in a straight line in the direction of the length of the bar, and the other a rotation round its axis. The former is communicated by a screw parallel to the bar, and working in a nut attached to the end of it. For the rotatory movement the bar carries a pinion, which is engaged by a rack placed horizontally and perpendicularly to the bar, and partaking of its backward and forward movement, but arranged so that its end must move along another bar placed at an angle with the former. It is this angle which determines the pitch of the rifling, and by substituting a curved guide-bar for the straight one, an increasing twist may be obtained in the grooves.

The projectile used with these guns is of a cylindrical form, but pointed at the head, and the moulds in which these shots are cast are so arranged that the head of the shot is moulded in iron, while the body is surrounded with sand. The rapid cooling induced by the contact of the cold metal causes the head of the shot to solidify very quickly, so that the carbon in the iron is not separated as in ordinary casting. In consequence of this treatment, the head of the shot possesses the hardness of steel, and is therefore well adapted for penetrating iron plates or other structures. The projectiles are turned in a lathe to the exact size, and then shallow circular cavities are bored in them, and into these cavities brass studs, which are simply short cylinders of a diameter slightly larger than the cavities, are forced by pressure. The projecting studs are then turned so as accurately to fit the spiral grooves of the guns. Thus the projectile in traversing the bore of the piece is forced to make a revolution, or part of a revolution, about its axis, and the rapid rotation thus imparted has the effect of keeping the axis of the missile always parallel to its original direction. Thus vastly increased accuracy of firing is obtained.

Fig. 95.—Millwall Shield after being battered with Heavy Shot.—Front View.

Shells are also used with the Woolwich rifled guns. The shells are of the same shape as the solid shots, from which they differ in being cast hollow, and having their interior filled with gunpowder. Such shells when used against iron structures require no fuse; they explode in coming into collision with their object. In other cases, however, the shells are provided with fuses, which cause the explosion when the shot strikes. Fig. 93, page 195, represents one of the 35–ton guns, made on the plan introduced by Mr. Fraser. This piece of ordnance is 16 ft. long, 4 ft. 3 in. in diameter at the breech, and 1 ft. 9 in. at the muzzle. The bore is about 1 ft. Each gun can throw a shot or bolt 700 lbs. in weight, with a charge of 120 lbs. of powder. It is stated that the shot, if fired at a short range, would penetrate a plate of iron 14 in. thick, and that at a distance of 2,000 yards it would retain sufficient energy to go through a plate 12 in. thick. The effect of these ponderous missiles upon thick iron plates is very remarkable. Targets or shields have been constructed with plates and timber backing, girders, &c., put together in the strongest possible manner, in order to test the resisting power of the armour plating and other constructions of our ironclad ships. The above two cuts, Figs. 95 and 96, are representations of the appearance of the front and back of a very strong shield of this description, after having been struck with a few 600 lb. shots fired from the 25–ton gun. The shots with chilled heads, already referred to, sometimes were found to penetrate completely through the 8 in. front plate, and the 6 in. of solid teak, and the 6 in. of plating at the back. The shield, though strongly constructed with massive plates of iron, only served to prove the relative superiority of the artillery of that day, which was at the time when our century had yet about thirty years to run. Up to 1876 no confidence was placed in steel as a resisting material, a circumstance perhaps not much to be wondered at, as its capabilities had not then been developed by the newer processes of manufacture, described in our article on Iron; nor had mechanicians acquired the power of operating with large masses of the metal. Since then it has come about that only steel is relied upon for efficiently resisting the penetration of projectiles, iron being held of no account except as a backing. There has always been a rivalry between the artillerist and the naval constructor, and this contest between the attacking and the defending agencies is well illustrated in the table on page 166, where the parallel advance in the destructive power of guns and in the resisting power of our war-ships is exhibited in a numerical form.

The 35–ton Fraser guns were at the time of their production humorously called in the newspapers “Woolwich infants”; but it was not long before they might in another sense be called infants in comparison with a still larger gun of 81 tons weight constructed at Woolwich shortly before iron-coiling and muzzle-loading were set aside. Fig. 97 shows the relative dimensions of the 35–ton and 81–ton guns: the latter was built up in the same way as the 9–inch gun described above, but the coils were necessarily longer and the chase was formed in three parts instead of two. The total length of this gun was 27 feet, and the bore was about 24 feet long and 14 in. in diameter, and the weight of the shot about 1000 lbs., with sufficient energy to penetrate at a considerable distance an iron plate 20 in. in thickness. It was for the manufacture of these very large guns that the great steam hammer, represented in Plate III., was erected at Woolwich.

The 81–ton gun was the largest muzzle-loader ever made in the national gun factory at the time when such huge weapons were in request; but in 1876 its dimensions were surpassed by those of a few 100–ton guns built at Elswick to the order of the Italian Government for mounting on their most formidable ironclads. These guns have a calibre of 17·72 inches, and are provided with a chamber of somewhat larger bore to receive the charge of powder. They are built up on the Armstrong shrinkage principle, and comprise as many as twenty different tubes, jackets, hoops, screws, etc., and are undoubtedly the most powerful muzzle-loading weapons ever constructed. It happened, just as these guns were completed, that the British Government, apprehensive at the time of a war with Russia, exercised its rights of purchasing two of them, one to be mounted at Gibraltar, the other at Malta.

The Elswick establishment soon afterwards surpassed all its former achievements in building great guns, by designing and constructing the huge breech-loaders, one of which forms the subject of our Plate XII. These are known as the Armstrong 110–ton guns; they are formed of solid steel throughout, and their weight is accurately 247,795 lbs., or 110 tons 12 cwts. 51 lbs. The total length of the gun is 43 ft. 8 in., and of this 40 ft. 7 in. is occupied by the bore, along which the rifling extends 33 ft. 1 in. The calibre of the rifled part is 16¼ in., and the diameter of the powder chamber is somewhat greater. The regulation charge of powder weighs 960 lbs., although the guns are tested with still greater charges. The weight of the projectile is 1,800 lbs., and it leaves the muzzle with a velocity of 2,128 ft. per second, which is equivalent to a dynamical energy of 56,520 foot-tons. What this means will perhaps be better understood, not by describing experiments such as those on the Millwall Shield, the results of which are depicted in Figs. 95 and 96, but by stating that if the shot from the 110–ton gun encountered a solid wall of wrought iron a yard thick, it would pass through it. The Elswick 110–ton gun is, in fact, the most powerful piece of ordnance that has ever been constructed. There are no trunnions to these great guns, but they are encircled by massive rings of metal, between which pass strong steel bands that tie the gun to its carriage, or, rather, to the heavy steel frame on which it is mounted, and which slides on a couple of girders. The force of the recoil acts on a hydraulic ram that passes through the lower part of the supporting frame. The whole working of the gun is done by hydraulic power, and, indeed, the same method has been applied by the Elswick firm to the handling of all heavy guns. By hydraulic power, maintained automatically by a pumping engine exercising a pressure of from 800 lbs. to 1,000 lbs. per square inch, are operated the whole of the movements required for bringing the cartridge and the projectile from the magazine; for unscrewing the breech block, withdrawing it, and moving it aside; for pushing home the shot and the cartridge to their places in the bore; for closing the breech and screwing up the block; for rotating the turret within which the gun is mounted, or in other cases for ramming the piece in or out, and for elevating or depressing it. It is, indeed, obvious that such ponderous masses of metal as form the barrels and projectiles of these 110–ton and other guns of the larger sizes could not be handled to advantage by any of the ordinary mechanical appliances. But by the application of the hydraulic principle, a very few men are able to work the largest guns with the greatest ease, for their personal labour is thus reduced to the mere manipulation of levers. On board ship the power required for working large guns has lately been sometimes supplied by a system of shafting driven by a steam engine and provided with drums and pulleys, exactly as in an engineer’s workshop. Great care has also been bestowed upon the mounting of the smaller guns, which are so nicely poised on their bearings and provided with such accurately fitted racks, pinions, etc., that a steel gun of 10 ft. in length can easily be pointed in any direction by the touch of a child’s hand. The mechanical arrangements are now so admirably adapted for facility of working that, unless in the rude shocks of actual warfare the nicely adjusted machinery is found to be liable to be thrown out of gear, these applications of the engineer’s skill may be considered as having done all that was required to bring our modern weapons to perfection.

With the construction of the 110–ton we arrive at a period when commences a new era in guns—and especially in the armament of war-ships—necessitated by various circumstances, amongst which may be named the invention of torpedoes and the building of swiftly moving torpedo-boats, and of still swifter “torpedo-boat catchers or destroyers”; so that guns that could be worked only at comparatively long intervals were at a great disadvantage. Again, about 1880, were published the records of a most elaborate and important series of researches conducted by Captain Noble and Sir F. Abel, the chemist of our War Department. They had investigated all the conditions attending the combustion of gunpowder in confined spaces, the nature and quantities of the products, the temperature and pressures of the confined gases, etc. The information thus afforded was extremely valuable; but besides this, direct experiments made with actual guns were carried out, more particularly at Elswick, in which the speed of the projectiles at every few inches of their travel along the bore of the piece was ascertained, and also the pressures of the powder gases at any point. The way in which this is done we shall explain on another page. (See article on Recording Instruments.)

So long as muzzle-loading was in use, guns were necessarily made short, for had they not to be run in from the port-holes and embrasures of forts in order to be loaded? Now there was an obvious disadvantage in this, for the projectile left the gun before the expansive force of the gases had been spent that could have imparted additional velocity. When however muzzle-loading was abandoned, and especially when strong and trustworthy steel became available for the construction of the gun throughout, there was no reason to waste in this way the power of the charge, so that barrels were made lighter, much longer in proportion to the calibre, and every part accurately adapted in strength to the strain to be resisted. For instances of increasing length, take the 38–ton 12–inch guns built up at Woolwich (of only seven pieces) for H.M.S. Thunderer (see Fig. 93), on Mr. Fraser’s plan. These had a bore equal to only 16 times their calibre, while in the Armstrong 100–ton guns the bore is 21 calibres long; and in the 110–ton guns the total length of the chase is 31 times the diameter of the rifled part. It has since been the practice to make the bore of guns from 30 to 40 calibres in length.

The effect of a longer chase used with an appropriate charge is very clearly and instructively shown by the diagram Fig. 98, which is by permission copied from the very comprehensive work by Messrs. E. W. Lloyd and A. G. Hadcock, entitled Artillery: its Progress and Present Position. The reader should not pass over this diagram until he has thoroughly understood it, for it is an excellent example of the graphic method of presenting the results of scientific investigations. At the lower part of the diagram there are drawn to scale half-sections of a long and of a short gun. The horizontal line above is marked in equal parts representing feet numbered from the base of the projectiles. The upright line on the left numbered at every fourth division is the scale for the pressures in tons per square inch on the base of the projectile, and these are represented by the height of the plain curves above the horizontal line at each point in the travel of the shot. The dotted lines represent in the same way, but not on the same scale as the former, the velocity with which the base of the projectile passes every point in the chase. The figures 2, 4, and 6 on the upright line at the right-hand side refer only to pressures: the velocities scale is such that the point where the dotted meets the right-hand one is 2,680 units above the horizontal line, as the middle upright in the same way is 1,561 high, and the heights of the dotted lines represent each on the same scale the velocities of the bases of the projectiles at the corresponding parts of the chases. The shorter gun has the rifled part of the chase 15·4 calibres long; the corresponding part of the longer is nearly 33 calibres. The short 7–inch gun has a charge of 30 lbs. of gunpowder, and its projectile weighed 115 lbs. The longer 6–inch gun was not charged with gunpowder, but with the more powerful modern explosive cordite (see Index), of which there was 19·5 lbs., and its projectile weighed 100 lbs. The charges were so adjusted that the shots had the same initial maximum pressure of 20 tons per square inch applied to them. Now the cordite, though much more powerful than gunpowder (that is, a given weight will produce far more gas), is slower in its ignition, continuing longer to supply gas. The maximum pressure, 20 tons in both cases, is suddenly attained by the gunpowder gases, when the shot has hardly moved 6 inches onward, and the pressure declines rapidly as the moving shot leaves more space for the gas; while the cordite gases produce their greatest pressure more gradually at a part where the shot is already about 20 inches on its way, and not only do their highest pressures continue for a greater distance,—but the decline is far less rapid than in the other case. It will be observed by the intersection of the dotted lines, that when the shots in each case have moved about 2 ft. their velocities are equal. They finally leave the muzzles with the velocities marked on the diagram, and if the reader will apply the formula given on page 174 he will obtain their respective energies in foot-lbs.; but for large amounts like these it is more usual to state the energy in foot-tons, which of course will be arrived at by dividing the foot-lbs. numbers by 2,240, and these will work out in the one case to 4978·9 ft.-tons, and in the other to 1942·5 ft.-tons. The shot from the long gun will therefore have more than 2½ times the destructive power of the other.

The operations required in constructing guns are multiform, and have to be very carefully conducted so that the workmanship shall be of the best quality. The finest ores are selected for reduction, and the steel is obtained by the Siemens-Martin process already described. It must be free from sulphur and phosphorus, and contain such proportions of carbon, silicon, and manganese as experience has shown to be best, and its composition is ascertained by careful chemical analysis before it is used. The fluid steel is run into large ladles lined with fire-brick, and provided with an opening in the bottom from which the metal can be allowed to run out into the ingot moulds, the size and proportions of these being in accordance with the object required; some admitting of as much as 80 tons at one operation. When a barrel or hoop is required of not less than 6 inches internal diameter the ingot is cut to the required length and roughly bored. The ingot is then heated, a long cylindrical steel bar is put through the hole, and under a hydraulic press the hot metal is squeezed into greater length and less diameter. The hole first bored through the ingot is of somewhat greater, and the steel bar (called a mandril) of less, diameter than required in the finished piece. Portions are cut from each end of what is now called the forging and subjected to mechanical tests: if these are satisfactory, the forging is rough bored and turned on the outside. It is then annealed, by being heated and allowed to cool very slowly. The next operation is to harden the metal by raising it to a certain temperature, at which it is immersed in rape oil until cold. Then the piece is again annealed, and fine-turned and bored. All these operations have to be performed not only on the barrel, but also on each hoop, before the hoops are shrunk on, and the greatest nicety of measurement is required in each piece. Then the gun has to be turned on the outside, the screw for the breech piece cut, the bore rifled, etc. The object of the annealing is to relieve the metal from internal strains. It will not be wondered at that months are required for the construction of the larger kind of guns. Thus at Elswick a 6 in. quick firing gun, upon which men are employed night and day, cannot be completed in less than five months, and sixteen months are required for making a 67–ton gun.

We may take as an illustration of the progress of modern artillery one of the products of the Elswick factory which has just been referred to, and for which the demand from all quarters has been unprecedentedly great, namely, the 4·7 inch gun. This weapon is mounted in various manners according to the position it has to occupy, whether for a land defence, or on ship-board between decks, or on the upper deck. The arrangement shown in Fig. 99, which is reproduced from Messrs. Lloyd & Hadcock’s work, is known as the centre pivot mounting, and is suitable for such a position as the upper deck of a ship. The reader should compare the proportions and mounting of this weapon with those of the old 32–pounder sketched in Fig. 90, observing the very much greater comparative length of the modern weapon, and the mechanism for elevating and training it (which, however, the scale of the drawing crowds into too small a space to show as it deserves). C is a projection from the breech, to which is attached the piston of the recoil press; at T is the handle for training, which actuates a worm at V; the elevation is regulated by the turning of the four-armed wheel. The long chase of the gun projects in front; but the mounting and the breech machinery are protected by shields of thick steel, of which the sections of two plates are denoted by the dark upright parts in front. These are fixed; but a movable plate above the gun can be raised or lowered into an inclined position, for better taking sights. In the figure this is shown as open and in a horizontal position. This gun is provided with sights by which it can be aimed at night; that is, the sights can be illuminated by small electric lamps suitably placed; the wires connecting these with voltaic battery cells carried on the mounting are indicated. The figure represents the gun as constructed about 1893, but the improvements that are continually being made have brought about some modifications in the details.

Very notable among the productions of the great Elswick factory are the quick firing guns. These were at first confined to guns of small calibre, such as the 6–pounders. They are, of course, all breech-loaders, and the powder and shot are both contained in a single metallic cartridge case. A more formidable weapon of the same class is the 45–pounder rapid firing gun, which, like the rest, is constructed entirely of steel, with a total length of 16 ft. 2½ in., a calibre of 4·724 in., and a length of bore equal to 40 diameters. The weight of this gun is 41 cwt., and it throws a shell of 45 lbs. weight with a 12–lb. charge of gunpowder. Quick firing guns having a calibre of 6 in. are now also made in great numbers for arming our ironclads. The breech block in the quick firing guns turns aside on a hinge, and after the introduction of the cartridge it is closed and screwed up to its place by a slight turn of a handle. The piece is then pointed and trained by aid of mechanical gearing as in the case of the heavier guns. But Mr. Hotchkiss has introduced a simpler method of elevating and training his 3–pounder and 6–pounder quick firing guns, by attaching to the rear, and unaffected by the recoil, a shoulder piece against which the marksman can lean, and move the weapon as he takes his aim. Though these guns weigh respectively 4½ cwt. and 7 cwt., they can thus be pointed with the greatest ease. The firing is done by pulling a trigger in what seems like the stock of a pistol. The empty cartridge case is automatically extracted from the firing chamber by the act of opening the breech, and it drops to the ground. Ten or twelve rounds per minute can be fired from these guns, and Lord Armstrong has advocated the use of a number of them for naval armament in preference to that of a few ordinary breech-loaders of more unwieldy dimensions. He has calculated that in a given time a far greater weight of metal can be projected from a vessel armed with quick firing guns than from one provided only with the heavier class of cannons.

The breech pieces in the Elswick guns are closed on the “interrupted screw” system—that is, a very large screw thread of V-shaped section is cut in the barrel at the breech end, and a corresponding thread on the principal part of the breech block, which is, of course, capable of rotating about the axis. The screw threads, however, are not continuous, segments parallel to the axis being cut away, the spaces in the outer thread corresponding with the projecting parts in the inner, and vice versÂ, so that when the block is pushed home, one very small part of a turn suffices to engage all the threads. The screw is also made conical, and is so cut into steps, as it were, that great resisting power is brought into play. The Elswick guns are provided with hydraulic buffers for checking the recoil, and the principle is applied in various modified forms. In some cases the pistons allow for the water a passage, which towards the end gradually diminishes. This is the arrangement for the 3–pounder rapid firing Hotchkiss gun, and the force of the recoil is made at the same time to compress two springs, which serve to return the gun to the firing position. This very handy gun is said to be able to fire twenty rounds per minute. In Mr. Vavasseur’s plan of mounting, the recoil is checked by ports, or openings, in the piston of a hydraulic cylinder being gradually closed, which is easily arranged by making a spiral groove within the cylinder, which gives a small axial motion to part of the piston.

An extremely effective plan for the defence of coasts and harbours was originated by Colonel Moncrieff, when about 1863 he contrived a method of mounting large guns on the disappearing system, by which almost complete protection against hostile fire is given to both gun and gunners. He utilizes the recoil as a means of bringing the gun down into a protected position the moment it has been fired, and retains this energy by a simple arrangement until the piece has been reloaded, when it is allowed to expend itself by again raising the gun above the parapet into the original firing position. The configuration and action of Colonel Moncrieff’s gun-carriage will be understood by an inspection of the annexed illustrations, where in Fig. 100 is shown the gun raised above the parapet and ready for firing. When the discharge takes place, the gun, if free, would move backwards with a certain speed, but the disposition of the mounting is such that this initial velocity receives no sudden check, the force being expended in raising a heavy counterpoise, and at the same time the gun is permitted to descend, while maintaining a direction parallel to its firing position. At the end of the descent, which, it must be understood, is caused by the force of the recoil, and not by the counterpoise, for this more than balances the weight of the gun, the latter is retained as shown in Fig. 101 until it has been reloaded; and when it has again to be fired, it is released so as to allow the descent of the counterpoise to raise it once more into position. The great advantage of this invention is the protection afforded to the artillerymen and gun while loading; and even the aiming can be accomplished by mirrors, so that the men are exposed to no danger, except from “vertical fire,” which involves but little risk.

Colonel Moncrieff took out a patent for his invention in 1864, but committed the practical working out of his idea to the firm of Sir W. G. Armstrong & Co., in whose hands the design was ultimately transformed from the original somewhat cumbersome arrangement of the mounting into the compact and manageable form shown in Fig. 102, which represents a 13·9 inch 68–ton breech-loading disappearing gun on the Elswick hydro-pneumatic mounting. The principle of hydraulic power is fully explained in our article on that subject, and an example of its application to cranes as devised by Sir W. Armstrong is there described. When guns began to be made very large, and projectiles weighing several cwts. had to be dealt with, the application of power in some form became essential for loading, running out, elevating, training, etc.; and though steam-power naturally was first used, hydraulic power was adopted at Elswick, and has been there applied to the mountings of large guns with the greatest success by Mr. G. W. Rendel. To mention the various arrangements in which this power is applied, or to attempt any description of the elaborate machinery by which it is regulated, would carry us far beyond our limits. But the powerful weapon depicted in Fig. 102 is designed to be worked only by the manual effort of a few men. In this mounting the pressure of condensed air sustains the gun in the firing position; that pressure, acting upon the water in the recoil presses, having previously forced up their rams so as to turn into a nearly vertical position the strong brackets or beams on which the trunnions are supported. The recoil is checked in the usual way by the forcing of the water through small ports or valves as the ram descends, but these valves are so arranged that the water is in part forced back into the air chamber, and there recompresses the air, to restore the power for again raising the gun. The pressure in the air chamber when the gun is down may be about 1,400 lbs. per square inch; when it is up this will be reduced to perhaps one half by the expansion of the air in doing work. We have here the reaction of compressed air taking the place of the gravity of the counterpoise originally designed. There are in this hydro-pneumatic mounting a number of adjusting appliances, such as forcing pumps, brakes, etc., for regulating the pressures, or quantity of liquid, as, for instance, when lowering the gun without any recoil action in operation. Then again, with any change in the weight of projectile or in the powder charge, there would be a corresponding change in the power of the recoil, and therefore the necessity for compensatory adjustments, which are made with great readiness. The nicety with which the parts are adapted to each other in this mounting must be obvious, when we observe the magnitude of the mass to be moved with the least delay, and brought to rest, quite gently and exactly, in a new position. Details cannot here be given even of the method by which the valves in the recoil cylinders are automatically controlled for this purpose. Means are also supplied for setting the gun, while still in its protected position, to the required angle of elevation or depression. The adjustment is made by the long rods attached near the breech and set at their lower ends to the position giving the intended angle to the raised gun. The varied and powerful strains to which the parts of this mechanism are subject, and which have had to be calculated and provided for, may be inferred from the enormous recoil energy of the gun, which under ordinary conditions amounts to no less than 730 foot-tons. The gun is provided with ordinary, and also with reflecting, sights, so that no one need be exposed to the enemy’s fire. Protective armour above the gun is not required, as the pit itself being usually on some elevation is imperceptible to the enemy, and the gun is visible but for a few seconds, forming a quite inconspicuous object. The pit in which the gun is mounted is commonly lined with concrete. Italy, England, Norway, Japan and other countries have appreciated the advantages of the disappearing system in providing the most powerful coast defences yet devised, and a great many guns have been mounted on this principle.

An extraordinary piece of ordnance is represented in Fig. 103. It is one of two huge mortars, the idea of which presented itself to Mr. Mallet during the Crimean War, the intention being to throw into the Russian lines spherical shells a yard in diameter, which would, in fact, have constituted powerful mines, rendering it impossible for the fortifications to continue tenable. Mallet’s original design was to project these shells from mortars of no less than 40 tons weight. When it was pointed out that the transport of so heavy a mass would be impracticable, the design was changed to admit of the mortar being made in pieces not exceeding eleven tons in weight, and built up where required. During the most active period in the siege of Sebastopol this plan was submitted to Lord Palmerston, who at once ordered two of these apparently formidable pieces to be constructed, without waiting for official examinations of the scheme, and the usual reports of experts,—promptness in this case being considered of the utmost importance. A contract was made with a private firm, who undertook to deliver them in ten weeks. But the difficulties attending such constructions not being understood at the time, delays arose, the contractors failed, and two years elapsed before the mortars were completed. In the meantime peace had been concluded, and the mortars were never fired against any hostile works; but experiments were made with one of them at Woolwich. The heaviest of the shells it was intended to project weighed 2,940 lbs., and for this it was proposed to use a charge of 80 lbs. of gunpowder. In the experiments the charges first used were low, but gradually increased: when it was found that after every few rounds repairs became necessary in consequence of the weak points in the construction, and after the nineteenth round the mortar was so much damaged that the trials were definitely discontinued. The other mortar, though mounted, was never fired, but remains at Woolwich, an object of some interest to artillerists, especially since there has been some talk of reverting to this very old-fashioned form of ordnance as a means of attacking ironclads in their most vulnerable direction by the so-called vertical fire. In one of the rounds of the Mallet mortar tried at Woolwich, a shell weighing 2,400 lbs. was thrown by a charge of 70 lbs. of gunpowder a distance of more than a mile and a half, and it buried itself in the soil to a very great depth.

For high-elevation firing, howitzers will more probably be the form of ordnance most in use. The range of the howitzer is determined by the angle at which it is elevated, whereas with the mortar it is chiefly by variation of the powder charge that the aim is adjusted. Many of the old short 9 in. muzzle-loaders have already been converted into 11 in. rifled howitzers, and these are likely to prove of great service in defending our harbours and channels against war vessels.

Some account has been given in a preceding article of the great steel works of Krupp & Co. at Essen, and the place has been noted as one of the greatest gun factories in the world during the second half of our century. The process there practised of casting crucible steel ingots, and already described, is precisely that used in the first stage of gun-making. The steel for guns put into the crucibles is a carefully adjusted mixture of one quality of iron puddled into steel and subjected to certain treatment; the other portion is made from a different quality of iron from which all the carbon has been puddled out. The cast ingot is forged under a great steam hammer, bored, turned, and steel hoops shrunk upon it, in several layers, and other operations are performed upon it like those which have already been mentioned. A 14 in. gun is said to require sixteen months for its manufacture, and its cost to be about £20,000.

Artillerists had long carried on a warm controversy as to the relative merits of wrought iron and steel in gun construction, the latter material being regarded with shyness on account of its want of uniformity as formerly produced. Krupp however began as early as 1847 to make guns of his excellent crucible steel, and through bad report and good report confined himself to this material until, it is asserted, by 1878 he had supplied over 17,000 steel guns of all calibres. He began by making a 3–pounder gun, but soon produced pieces of larger size, all of which were bored and turned out of solid masses of metal. At a later period the plan of shrinking on strengthening hoops of steel was adopted. The Krupp guns have found extensive favour, and many very heavy ones have been made, some indeed of greater weight than the 110–ton Armstrong; but the excess of weight is due to the mass of metal which the Krupp construction of the breech mechanism requires. Thus Krupp’s 120–ton gun has a muzzle energy of but 45,796 foot-tons, while that of the Elswick piece is 55,105 foot-tons.

The breech arrangement in the Krupp guns consists of a lateral slot into which slides a closing block after the charge has been inserted from the rear. An obsolete form of this breech piece is seen in Fig. 104, which represents a 32–pounder gun such as was used in sieges by the Prussians in the Franco-German War. It will be observed here that the slot and breech piece are of rectangular form; but this shape, causing the piece to be weak where most strength was required, was afterwards altered into a D-shaped section, the curved side being of course to the rear. That difficulty which baffled the earliest attempts at breech-loading is the same that has given much trouble to modern gunmakers. It consists in so closing the breech that no escape of the powder gases can take place there at the moment of discharge. When we remember that the momentary pressure of the gases in the powder chamber may amount to more than 40 tons on the square inch, we can well understand the enormous velocity with which they will rush forth from even the smallest interspace between the base of the gun and the breech block, but we can hardly realise without actual inspection the mechanical action they produce in their passage: when once the escape occurs, a channel is cut in the metal as if part had been removed by an instrument, and the piece in that condition is disabled for further use. Several devices are in use obtaining perfect closure of the breech, which is technically called obturation (Latin, obturare, to close up). One of these consists in fitting closely into the circumference of the bore a ring of very elastic steel, turned up at the edges towards the powder chamber. The gas pressure forces the edge of this ring still more closely against the interior of the powder chamber, much in the same way as the Bramah collar acts in the hydraulic press (see Fig. 165). The shaded circle shown on the breech piece in Fig. 104 is an additional device for obtaining obturation. The Broadwell ring, as the above-mentioned contrivance is called, is not used in English guns, but another plan of obtaining a gas-joint has been much adopted, in which a squeezable pad is by compression forced outwards to close up the bore.

A very long range was claimed for Krupp’s guns at the time of the Franco-German War, for at the siege of Paris (1870) it was said they could hurl projectiles to the distance of five miles, though probably there was some exaggeration in this statement. There is no doubt however that the Prussians had very effective and powerful artillery, as may be gathered from Fig. 105, which is taken from a photograph of part of the fortifications of Strasburg after the bombardment of that fortress. The explosive shells used by the Prussians against masses of troops were not precisely segment shells of the form already described, but the principle and effect were the same, for the interior was built up of circular rings, which broke into many pieces when the shell exploded.

Out of the very numerous forms in which modern ordnance is constructed, we have been able to select but a few examples for illustration and description. These will suffice, it is hoped, to give an idea of the progress that the century has witnessed. It would be beyond our scope to give details of the ingenious mechanical devices that have come to be applied to guns: such as the breech-closing arrangements, the various ways in which recoil is controlled and utilized, etc. A good illustration, had space permitted, of the scientific skill applied to ordnance would be found in the contrivances fitted to certain projectiles in order to determine their explosion at the proper moment. These are very different from the cap or time fuse that did duty in the first half of the century. We have indeed said little of the projectiles themselves beyond mention of the Palliser chilled shot and the obsolete studded projectiles. We have not explained how bands of copper, or other soft metal, are put round a certain part of the shot or shell, in order that, being forced into the grooves, the axial rotation may be imparted, or how windage is prevented by “gas checks” attached to the base of the projectiles. We must now be contented to conclude this section by showing the structure of two kinds of explosive shells which have been much used.

Shrapnel shell takes its name from Lieutenant Shrapnel, who was its inventor about the end of last century, but the projectile began to be used only in 1808. Fig. 105a is a section showing the shell as a case containing a number of spherical bullets, of which in the larger shells there are very many, the interspaces being filled with rosin, poured in when melted; the bullets are thus prevented from moving about. The figure shows the shell without the fuse or percussion apparatus, which screws into the hollow at the front. The bursting charge of gunpowder is behind the bullets, and when it explodes they travel forward with a greater velocity than the shell, but with trajectories more or less radiating, carrying with them wide-spreading destruction and death.

A shrapnel shell may be said to be a short cannon containing its charge of powder in a thick chamber at the breech end; the sides of the fore part of the shell are thinner than those of the chamber, and may be said to form the barrel of the cannon. This cannon is loaded up to the muzzle with round balls, which vary with the shell in size. An iron disc between the powder and the bullets represents the wad used in ordinary fowling-pieces. A false conical head is attached to the shell, so that its outward appearance is very similar to that of an ordinary cylindro-conoidal shell: that is to say, it looks like a very large long Enfield bullet. The spinning motion which had been communicated to the shell by the rifling of the gun from which it had been fired causes the barrel filled with bullets to point in the direction of the object at which the gun has been aimed. Consequently, when the shrapnel shell is burst, or rather fired off, the bullets which it contained are streamed forward with actually greater velocity than that at which the shell had been moving; and the effect produced is similar to firing grape and canister from a smooth-bore cannon at a short range.

Segment shells were first brought into use by Lord Armstrong in 1858 in connection with his breech-loading guns. The segment shell consists of a thin casing like a huge conical-headed thimble, with a false bottom attached to it. It is filled with small pieces of iron called “segments,” cast into shapes which enable them to be built up inside the outer casing into two or more concentric circular walls. The internal surface of the inmost wall forms the cavity of the compound or segment shell, and contains the bursting charge. The segment shell is fitted with a percussion fuse, which causes it to explode when it strikes. In the shrapnel shell, the powder charge is situated in rear of the bullets, and consequently produces the chief effect in a forward direction. In the segment shell, the powder is contained inside the segments, and therefore produces the chief effect in a lateral direction. When the shrapnel shell is burst at the right moment, its effect is greatly superior to that of the segment shell; on the other hand, the segment shell, when employed at unknown or varying distances, is far more unlikely to explode at the proper time.

Shrapnel and segment shells can be used with field artillery, i.e., 9–pounders, 12–pounders, 16–pounders; and also with heavy rifled guns in fortresses, viz., 40–pounders, 64–pounders, 7–in. and 9–in. guns. But the conditions of their service are very different in each case. With regard to field artillery, the distance of the enemy is rarely known, and is constantly changing, and hence the men who have to adjust the fuses would probably be exposed to the fire of the enemy’s artillery, and, consequently, could not be expected to prepare the fuses with the great care and nicety which are absolutely necessary to give due effect to the shells. There are, however, some occasions when the above objections would not hold good—as, for instance, when field artillery occupy a position in which they wait the attack of an enemy advancing over ground in which the distances are known.

Segment shells require no adjustment of their percussion fuse. They enable the artillerymen to hit off the proper range very quickly, since the smoke of the shell which bursts on striking tells them at once whether they are aiming too high or too low.

With regard, however, to the service of heavy rifled guns in fortresses, the conditions are quite different. In the first place, the distance of all objects in sight would be well known beforehand; and in the second place, the fuses of the shells would be carefully cut to the required length in the bomb-proofs, where the men would be completely sheltered. The 7–in. shrapnel contains 227 bullets, and a 9–in. shrapnel would contain 500 bullets of the same size, and these shells could be burst with extraordinary accuracy upon objects 5,000, 6,000, or 7,000 yards off.

MACHINE GUNS.

The name of machine guns has been applied to arms which may be regarded as in some respects intermediate between cannons and rifles, since in certain particulars they partake of the nature of both. Like the former, they are fired from a stand or carriage, and in some of their forms require more than one man for their working: in the calibre of their barrels and the weight of their projectiles, they are assimilated to the rifle, but they are capable of pouring forth their missiles in a very rapid succession—so rapid indeed as practically to constitute volley firing. The firing mechanism of the machine gun has always an automatic character, but the rifle has acquired this feature, so that it cannot be made a distinguishing mark: on the other hand, since machine guns have been made to discharge projectiles of such weights as 1 lb. or 3 lb. there is nothing to separate them from quick-firing ordnance unless it be the automatic firing.

The idea of combining a number of musket-barrels into one weapon, so that these barrels may be discharged simultaneously or in rapid succession, is not new. Attempts were made two hundred years ago to construct such weapons; but they failed, from the want of good mechanical adjustments of their parts. Nor would the machine gun have become the effective weapon it is, but for the timely invention of the rigid metallic-cased cartridge. Several forms of machine guns have in turn attracted much attention. There is the Mitrailleur (or Mitrailleuse), of which so much was heard at the commencement of the Franco-German War, and of whose deadly powers the French managed to circulate terrible and mysterious reports, while the weapon itself was kept concealed. Whether this arose from the great expectations really entertained of the destructive effects of the mitrailleur, or whether the reports were circulated merely to inspire the French troops with confidence, would be difficult to determine. Our own policy in regard to new implements of war is not to attempt to conceal their construction. Experience has shown that no secret of the least value can long be preserved within the walls of an arsenal, although the French certainly apparently succeeded in surrounding their invention with mystery for a while. The machine gun, or “battery,” invented by Mr. Gatling, an American, is said by English artillerists to be free from many defects of the French mitrailleur. In 1870 a committee of English military men was appointed to examine the powers of several forms of mitrailleur, with a view to reporting upon the advisability or otherwise of introducing this arm into the British service. They recommended for certain purposes the Gatling battery gun.

Fig. 105b.—The Gatling Gun.—Rear View.

In the Gatling the barrels, ten in number, are distinct and separate, being screwed into a solid revolving piece towards the breech end, and passing near their muzzles through a plate, by which they are kept parallel to each other. The whole revolves with a shaft, turning in bearings placed front and rear in an oblong fixed frame, and carrying two other pieces, which rotate with it. These are the “carrier” and the lock cylinder. Fig. 105b gives a rear view, and Fig. 105c a side view, of the Gatling battery gun. The weapon is made of three sizes, the largest one firing bullets 1 in. in diameter, weighing ½ lb., the smallest discharging bullets of ·45 in. diameter. The small Gatling is said to be effective at a range of more than a mile and a quarter, and can discharge 400 bullets or more in one minute. Mr. Gatling thus describes his invention:

“The gun consists of a series of barrels in combination with a grooved carrier and lock cylinder. All these several parts are rigidly secured upon a main shaft. There are as many grooves in the carrier, and as many holes in the lock cylinder, as there are barrels. Each barrel is furnished with one lock, so that a gun with ten barrels has ten locks. The locks work in the holes formed in the lock cylinder on a line with the axis of the barrels. The lock cylinder, which contains the lock, is surrounded by a casing, which is fastened to a frame, to which trimmers are attached. There is a partition in the casing, through which there is an opening, and into which the main shaft, which carries the lock cylinder, carrier, and barrels, is journaled. The main shaft is also at its front end journaled in the front part of the frame. In front of the partition in the casing is placed a cam, provided with spiral surfaces or inclined planes.

“This cam is rigidly fastened to the casing, and is used to impart a reciprocating motion to the locks when the gun is rotated. There is also in the front part of the casing a cocking ring which surrounds the lock cylinder, is attached to the casing, and has on its rear surface an inclined plane with an abrupt shoulder. This ring and its projection are used for cocking and firing the gun. This ring, the spiral cam, and the locks make up the loading and firing mechanism.

“On the rear end of the main shaft, in rear of the partition in the casing, is located a gear-wheel, which works to a pinion on the crank-shaft. The rear of the casing is closed by the cascable plate. There is hinged to the frame in front of the breech-casing a curved plate, covering partially the grooved carrier, into which is formed a hopper or opening, through which the cartridges are fed to the gun from feed-cases. The frame which supports the gun is mounted upon the carriage used for the transportation of the gun.

“The operation of the gun is very simple. One man places a feed-case filled with cartridges into the hopper; another man turns the crank, which, by the agency of the gearing, revolves the main shaft, carrying with it the lock cylinder, carrier, barrels, and locks. As the gun is rotated, the cartridges, one by one, drop into the grooves of the carrier from the feed-cases, and instantly the lock, by its impingement on the spiral cam surfaces, moves forward to load the cartridge, and when the butt-end of the lock gets on the highest projection of the cam, the charge is fired, through the agency of the cocking device, which at this point liberates the lock, spring, and hammer, and explodes the cartridge. As soon as the charge is fired, the lock, as the gun is revolved, is drawn back by the agency of the spiral surface in the cam acting on a lug of the lock, bringing with it the shell of the cartridge after it has been fired, which is dropped on the ground. Thus, it will be seen, when the gun is rotated, the locks in rapid succession move forward to load and fire, and return to extract the cartridge-shells. In other words, the whole operation of loading, closing the breech, discharging, and expelling the empty cartridge-shells is conducted while the barrels are kept in continuous revolving movement. It must be borne in mind that while the locks revolve with the barrels, they have also, in their line of travel, a spiral reciprocating movement; that is, each lock revolves once and moves forward and back at each revolution of the gun.

“The gun is so novel in its construction and operation that it is almost impossible to describe it minutely without the aid of drawings. Its main features may be summed up thus: 1st.—Each barrel in the gun is provided with its own independent lock or firing mechanism. 2nd.—All the locks revolve simultaneously with the barrels, carrier, and inner breech, when the gun is in operation. The locks also have, as stated, a reciprocating motion when the gun is rotated. The gun cannot be fired when either the barrels or locks are at rest.”

There is a beautiful mechanical principle developed in the gun, viz., that while the gun itself is under uniform constant rotary motion, the locks rotate with the barrels and breech, and at the same time have a longitudinal reciprocating motion, performing the consecutive operations of loading, cocking, and firing without any pause whatever in the several and continuous operations.

The small Gatling is supplied with another improvement called the “drum feed.” This case is divided into sixteen sections, each of which contains twenty-five cartridges, and is placed on a vertical axis on the top of the gun. As fast as one section is discharged, it rotates, and brings another section over the feed aperture, until the whole 400 charges are expended.

After a careful comparison of the effects of field artillery firing shrapnel, the committee concluded that the Gatling would be more destructive in the open at distances up to 1,200 yards, but that it is not comparable to artillery in effect at greater distances, or where the ground is covered by trees, brushwood, earthworks, &c. The mitrailleur, however, would soon be knocked over by artillery if exposed, and therefore will probably only be employed in situations under shelter from such fire. An English officer, who witnessed the effects of mitrailleur fire at the battle of Beaugency, looks upon the mitrailleur as representing a certain number of infantry, for whom there is not room on the ground, suddenly placed forward at the proper moment at a decisive point to bring a crushing fire upon the enemy. Many other eye-witnesses have spoken of the fearfully deadly effect of the mitrailleur in certain actions during the Franco-German War.

Mr. Gatling contends that, shot for shot, his machine is more accurate than infantry, and certainly the absence of nerves will ensure steadiness; while so few men (four) are necessary to work the gun that the exposure of life is less. No re-sighting and re-laying are necessary between each discharge. When the gun is once sighted its carriage does not move, except at the will of the operator; and the gun can be moved laterally when firing is going on, so as to sweep the section of a circle of 12° or more without moving the trail or changing the wheels of the carriage. The smoke of battle, therefore, does not interfere with its precision.

Whatever may be the part this new weapon is destined to play in the wars of the future, we know that every European Power has now provided itself with some machine guns. The Germans have those they took from the French, who adhere to their old pattern. The Russians have made numbers of Gatlings, each of which can send out, it is said, 1,000 shots per minute, and improvements have been effected, so as to obtain a lateral sweep for the fire.

A competitor to the Gatling presents itself in the Belgian mitrailleur, the Montigny, Fig. 105d. This gun, like the Gatling, is made of several different sizes, the smallest containing nineteen barrels and the largest thirty-seven. The barrels are all fitted into a wrought iron tube, which thus constitutes the compound barrel of the weapon. At the breech end of this barrel is the movable portion and the mechanism by which it is worked. The movable portion consists mainly of a short metallic cylinder of about the same diameter as the compound barrel, and this is pierced with a number of holes which correspond exactly with the position of the gun-barrels, of which they would form so many prolongations. In each of the holes or tubes a steel piston works freely; and when its front end is made even with the front surface of the short cylinder, a spiral spring, which is also contained in each of the tubes, is compressed. The short cylinder moves as a whole backwards and forwards in the direction of the axis of the piece, the movement being given by a lever to the shorter arm of which the movable piece is attached. When the gun is to be loaded this piece is drawn backwards by raising the lever, when the spiral springs are relieved from compression, and the heads of the pistons press lightly against a flat steel plate in front of them. The withdrawal of the breech-block gives space for a steel plate, bored with holes corresponding to the barrels, to be slid down vertically; and this plate holds in each hole a cartridge, the head of each cartridge being, when the plate has dropped into its position, exactly opposite to the barrel, into which it is thrust, when the movable breech-block is made to advance. The anterior face of this breech-block is formed of a plate containing a number of holes again corresponding to the barrels, and in each hole is a little short rod of metal, which has in front a projecting point that can be made to protrude through a small aperture in the front of the plate, the said small apertures exactly agreeing in position with the centres of the barrels, and being the only perforations in the front of the plate. The back of the plate has also openings through which the heads of the pistons can pass, and by hitting the little pieces, or strikers, cause their points to pass out through the apertures in front of the plate, and enter the base of the cartridges, where fulminate is placed. The plate filled with cartridges has a bevelled edge, and the points of the strikers are pushed back by it as it descends. The heads of the pistons are separated until the moment of discharge from the recesses containing the strikers by the flat steel plate or shutter already mentioned. The effect, therefore, of pushing the breech-block forward is to ram the cartridges into the barrels, and at the same time the spiral springs are compressed, and the heads of the pistons press against the steel shutter which separates them from the strikers, so that the whole of the breech mechanism is thus closed up. When the piece is to be fired a handle is turned, which draws down the steel shutter and permits the pistons to leap forward one by one, and hit the strikers, so that the points of the latter enter the cartridges and inflame the fulminate. The shutter is cut at its upper edge into steps, so that no two adjoining barrels are fired at once. The whole of the thirty-seven barrels can be fired by one and a quarter turns of the handle, which may, of course, be given almost instantly, or, by a slower movement, the barrels can be discharged at any required rate.

The barrels of the machine guns we have described do not, as is generally supposed, radiate; on the contrary, they are arranged in a perfectly parallel direction. In consequence of this, the bullets are at short ranges directed nearly to one spot. The Gatling gun was adopted as a service weapon by the British navy, and in several minor actions it had proved effective, but in its original form it was superseded by the Gardner gun, in which the barrels are fixed horizontally side by side, and are in number five or fewer; each barrel is able to fire 120 rounds per minute. A new system of feed was afterwards applied to the Gatling gun by Mr. Accles, by means of which this gun was greatly improved and its rate of firing was increased to more than 1,000 rounds per minute; indeed, 80 rounds have been fired from it within 2 seconds. The Gatlings in this improved form have ten barrels, and are provided with feed drums, each containing 104 cartridges, and capable, when empty, of being almost instantly replaced by a full one. The contents of one drum can, if necessary, be discharged in about 2¼ seconds, so that in this time 104 rifle bullets would be fired; or considerably more than the rate of 1,000 rounds per minute could easily be maintained. The weapon is so mounted, that without moving its carriage it can be pointed at any angle of elevation or depression, and through a considerable lateral range.

Mr. Nordenfelt has brought out a machine gun, which, on account of the simplicity and strength of its firing mechanism, has proved the most reliable weapon of its class, and it also has been adopted into the British service, and indeed into that of nearly every nation in the world. In this gun there are five barrels arranged as in the Gardner, but the firing is operated by a lever working backwards and forwards at the rate of 600 rounds per minute.

In the firing of all these weapons, by turning a crank, or moving a lever at one side, any attempt at exact aiming must obviously be difficult if not impossible, from the liability of the gun to get moved. Several designs have been proposed for making the firing mechanism entirely automatic so as to require no effort on the part of the firer, whose attention can then be directed solely to pointing the piece. It would not be easy to explain in detail the way in which this is accomplished in these very ingenious guns; for while the principle of their action is sufficiently clear, namely, that the force of the recoil is made to extract the spent cartridge, open the breech, insert a fresh cartridge, close the breech, and fire the charge, the mechanism of the reacting springs, etc., by which this is effected could scarcely, even by the aid of elaborate diagrams, be made intelligible to any other than a gunsmith. The Maxim is one of those automatic guns: it has but one barrel, and after the first discharge it will go on firing with marvellous rapidity the cartridges supplied to it in a continuous chain, and this without any deviation from such direction as may be given to it by the operator, for he has neither crank to turn nor lever to move, but merely sits behind an iron shield directing the weapon at will, which, without interference, fires hundreds of shots per minute from one barrel, so long as the long bands of cartridges are supplied to it.

Mr. Nordenfelt and Mr. Hotchkiss have also both contrived quick firing guns for 1–lb., 3–lb., and 6–lb. projectiles, and these, it has been thought, will be of great service in naval warfare as against torpedo boats.

Though the automatic mechanism, whereby the breech operations are all performed by the force of the recoil of the barrel, which is allowed to slide backwards, and is then returned to its place by a spring, is too complicated for illustration here, mention may be made of a quite recent device by which the recoil action is dispensed with, and the mechanism so far simplified that scarcely more than half the number of parts in the lock mechanism are required. Imagine a closed tube beneath the barrel, parallel to it, and communicating with it only by a small boring near the muzzle; through this opening the expanding gases will pass, in a degree depending on its size and position, and by their action on a piston near the breech, impulses are supplied that will actuate the lock mechanism so long as cartridges are supplied, as they may be in a continuous band. A weapon of this construction has been already tried, and its discharges are so rapid that the sound of them is described as being quite deafening. This plan appears to be equally applicable to small arms, and to machine or field guns. A very effective gun of the kind, which fires ordinary rifle bullets, has been contrived by Mr. Hotchkiss, and is represented in Fig. 105e. It is capable of sending forth as many as 1,000 shots in one minute.

Modern ordnance has required certain modifications in the making of gunpowder, so that the original name of powder would now hardly be applicable at all. The large charges now used, if introduced in the form of fine powder, would certainly shatter the guns from the suddenness of the exploding force. Hence the material is made up into larger or smaller masses, generally rounded like small pebbles. The explosive used for the huge 110–ton guns presents itself in the form of chocolate-coloured hexagonal prisms, two or three inches long and about an inch in diameter. These are obtained by compressing the specially prepared material into moulds with a hydraulic press. The reason for this process is that, in order to obtain precision and uniformity in the effects, not only must the composition of the powder be always the same, but the size, shape, weight, and number of the several portions that make up the charge must be invariable. It has not been found possible to fire one of these monster guns many times without such signs of deterioration as would suggest a short “life” for each of them. But the greatest necessity for modern fire-arms is a smokeless powder or other explosive. It is obvious that the advantages of quick firing, whether of large or of small fire-arms, are greatly reduced if the soldier or gunner is prevented by smoke from taking aim. The invention of a smokeless gunpowder has several times been announced, and great advances have, indeed, been made towards its realization. Certain compositions, which appeared to meet the requirement of being practically smokeless, have, however, been found liable to chemical changes, or to corrode the bore, or to possess other objectionable properties. In this country the explosive coming into use as best adapted for quick firing guns, etc., presents itself in appearance like whitish or grey strings, and has hence received the name of cordite. The composition and mode of manufacture of these new substitutes for gunpowder are not readily disclosed, each military authority jealously guarding its own secrets. The problem of smokeless powder has, however, been almost completely solved, for at a military review that took place on the Continent in 1889, the discharge of the rifles (loaded with blank cartridges, of course) is said to have been attended with no more smoke than the puff of a cigar. The new invention will cause some changes in military tactics, for the manoeuvres formerly executed under cover of the battle smoke will no longer be possible. Some particulars as to the nature of smokeless powders will be found in the article on “Explosives.”