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ascertained fact, and has, consequently, been laid aside as that which need never again be questioned. It has become so intimately associated with the science of gunnery, that the attempt to substitute another theory, to assign another law of force, may be deemed by many the wandering of an erratic mind, or the presumption of an ignorant man. But the general acceptance of a theory is no proof that it is the most true and most perfect that will ever be presented; nor is it any evidence of a want of reverence for such men as Robins and Hutton, that we believe and assert that no individual is without error or has attained the whole truth ; that no authority, however great, should determine and settle every principle in philosophy.

“The theory of recoil, as at present established, has, no doubt, formed the groundwork for the belief of many who, unfortunately, in making their calculations, make no allowance whatever for the friction alluded to in the formula, nor for other causes of retardation: Military experiments, which were carried on in the United States on a large scale, have proved, that by increasing the charge of powder beyond one-third of the weight of the shot, the recoil is increased in a much higher ratio than the initial velocity of the shot.' The results of experiments with the gun-pendulum have also been found to be frequently at variance with those obtained from the ballistic pendulum ; and these variations I have found increased more and more as the distance was increased from the gun. Indeed, the great difficulty of hitting the ballistic pendulum fairly in the centre at long ranges has rendered that mode of carrying on experiments next to impossible. There are, however, other methods of conducting experiments, by which, with collateral evidence, great additional light may be thrown on the subject in question.

“ The cause of all motion is the presence of force in the moving body. The degree of the effect is in proportion to the cause; in other words, add to, or take from, the force in action upon given matter, and the quantity of motion is changed proportionally. A certain quantity of gunpowder contains a certain amount of force ; the question then is, how can we employ that force so as to obtain the greatest beneficial result from it? The explosion or force of gunpowder is repulsion among the atoms when assuming the form of air. The force of repulsion does not operate by a single impulse, but through a repetition of impulses, or a continued action, of which the effect is accumulated in the inertia of matter; thus, all great velocities are the terminations of an accelerated motion. As in every case of repulsion, two objects at least must be concerned, there can be no motion or action without a concomitant or opposite motion or reaction; it is therefore clear that the one must be repelled just as much as the other, although with a difference of velocity proportioned to the difference of size. The extraordinary action of gunpowder on the shot, the barrel, and the fore part of the stock, although appearing so sudden, is not an instantaneous but a gradual and therefore accelerating action; so is the recoil or reaction of the back part of the gun. The action or movement of the charge commences comparatively slowly at first, so does the reaction or recoil. The action of the charge and gradual increase of the gas, all along the barrel, is the cause; the action of recoil is the effect. The cause begins with the first movement of charge, and ends with the charge leaving the barrel. The retardation of the shot in passing up the barrel and the acceleration of the recoil take place within so short a time that it is not apparent to our senses, and, therefore, to some may appear momentary ; but the mind perceives the nature of the phenomenon as distinctly as if a large ball were rolled against the end of a long steel spring, and thrown back again from it.

“For the same reason that all great velocities require continued action or repeated impulse to produce them, so do they also to destroy them—the inertia of motion and of rest being exactly equal. The perfection of machinery depends much on diminishing among the moving parts the resistance which arises from friction. The explosion of gunpowder being a repulsion among the atoms when assuming the form of air, its greatest efficacy would be destroyed if the shot were prevented by unnecessary friction from starting gradually on its course with the very slightest force which first affects it. Even such apparent trifles as certain unguents increase, and others decrease the friction of quiescence—that is, increase or diminish the force requisite to produce the first movement. At this instant the action of the powder is comparatively slight, so is the reaction by friction, &c., and so is also the force of the recoil ; for the action of the charge in passing through the last three quarters of the barrel-overcoming friction and other causes of retardation—is the great cause of the recoil which is felt, unless, indeed, the charge is improperly jammed down when loading. This may be proved by cutting off three-fourths of the barrel and firing the same quantity of powder and shot from a recoil-rest. It would then be seen that it is not the original repulsion which caused the motion that man uses as his servant, but the momentum gradually accumuluted by such free and unopposed repulsion, and the progressive, though rapid, ignition of all the particles of the powder.

“ Of friction there are two kinds. The first is denominated sliding, and the second rolling friction. They are governed by the same laws, though the former is much greater in amount than the latter, under given circumstances. A round ball fired from a smooth bore will leave the muzzle with greater velocity than an elongated bullet fired from a riflethe calibre of both and the charge of powder being the same —but the recoil of the smooth-bore gun will be less than that of the rifle, simply because a very small proportion of the surface of the round ball, which has a rolling motion, can ever come in contact at the same time with the sides of the barrel. There is, therefore, less friction, and, consequently, less retardation to the accumulating speed of the round ball before it reaches the muzzle : still action and reaction will be equal, as the extra force which the bullet carries with it, after leaving the muzzle, is just so much force deducted or taken from the friction and recoil—the first being the cause of the greater effect in the second. This is easily proved by firing both bullets through a revolving meter from à recoil-rest. It may be added, however, that, if both bullets were fired at the same instant, at the same elevation, the elongated bullet would soon overtake the round one and pass it, as the latter, being lighter, would sooner be retarded by the friction and resistance of the external air. This may also be easily proved by noting the degrees of elevation necessary to make both bullets range the same distance.

“ If a similar round ball were cast into smaller shot, say thirty-two to the ounce, it would be found, by the revolving meter and recoil-rest, that the initial velocity of these would be less than the single ball, and the recoil considerably greater. The explanation is this : in consequence of there being a number of small shot instead of a single large one, they would lie, when loaded, in a cylindrical position, each shot of the outer circle touching the sides of the barrel ; so that in the aggregate they would occasion greater friction, and, consequently, greater retardation to their own progress in passing up the barrel-action and reaction would, however, still be equal.

“ In like inanner an equal weight of No. 1, or eighty pellets to the ounce, will leave the muzzle with a greater velocity and less recoil than No. 6, or two hundred and seventy pellets to the ounce; the smaller shot approaching nearer (and the more so as it is smaller) to the solid form of an elongated cylindrical bullet; in fact, an elongated bullet is but a more considerable number of particles or atoms of lead lying close together, and, if of a cylindrical form, causing greater friction on the sides of the barrel.

“This closeness of the pellets and their tendency to cause more or less friction in passing up the barrel may be seen at a glance, hy those who are acquainted with the nature of friction, on pouring an ounce and a half or two ounces of each sort of shot into a glass tube the size of a gun barrel -the one sort to be poured on the top of the other, with a wadding between each two. A careful examination of such a collection should teach the sportsman, that the smaller the shot the less in weight he should use, if he wishes to insure a high velocity. By reducing the quantity he would also reduce the recoil.

“Any addition to the usual quantity of shot will cause a greater amount of friction in its passage, just the same as adding to the length of the cylindrical portion of a rifle bullet. Thick tight wadding also retards, and adds to the friction of the charge. When the barrel becomes foul the friction is also increased. Cartridges, which might easily he made on an improved plan, cause more friction than loose shot; and cartridges with bone dust still more, though, in consequence

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of the shot being longer kept together in a mass, the shot

In fact, anything that increases the friction increases also the recoil, and lessens the initial velocity of the shot. The very reprehensible method of freeing or relieving the bore—that is, making it somewhat wider towards the breech—creates also a greater amount of friction, by retarding the passage of the shot. This plan was much patronized at one time by the Americans, but it has lately, and very properly, been exploded by the United States Government as unscientific, and worse than useless. It would be difficult, however, to convince some people that it is so : for many have an idea that an advantage is gained by retarding the shot until the gases evolved by the ignited powder have time to act; but, as these gases are rapidly though progressively evolved, any resistance must operate injuriously, as the velocity of the shot cannot possibly increase after it has left the muzzle. Moreover, if a cartridge be used, it must sit too easy in a freed bore, allowing a portion of the gases to escape past it, and mix with the already condensing air in front of the charge in the barrel, causing greater recoil and retardation to the shot. If loaded with loose shot it must cause greater friction, as the mass of shot must be contracted and lengthened before it can leave the muzzle, greater recoil and diminished velocity being the result. A barrel so relieved may shoot with more velocity than one which is supposed to be a perfect cylinder; but a careful examination of both, with all their accessories, will show that such relief alone is not the true cause of the superiority.

“In firing with some barrels and certain charges it often happens that a portion of the powder employed is driven out in an unconsumed state ; it may therefore appear feasible that by retaining the shot a sufficient length of time this portion may be brought to bear upon it; but the cause of the powder not being wholly consumed must be attributed to the practice of ramming down the charge too tightly, or charging with more powder than the length and calibre of the barrel will beneficially burn, and not to the shot passing out too freely. The object of granulating or corning powder is to enable the flame to play freely amongst the mass. The charge, therefore, should never be tightly rammed down, or

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