Great substance was at one time considered necessary for accurate firing, it being supposed necessary to prevent vibrations in the barrel; this is true within certain limits, and the heavier the charge, the heavier the metal ought to be, especially at the breech, but diminishing the thickness, has been proved in no wise to lessen the accuracy. A heavy barrel also lessens recoil, but it would be folly to carry more weight than would neutralize the recoil which could be produced by a greater charge of powder than could be consumed in a given length of barrel. ~Size of bore.~ The two grand requirements of a soldier’s gun are, celerity of loading, combined with accuracy at long ranges; and the distance at which he should have the power of firing, should be limited by the strength of his eye. The weight of the projectile being fixed (·530 grs.), good shooting at extreme distances can only be obtained by reducing the diameter of the bore, which, lessening the frontage of the bullet, causes it to experience less resistance from the air; it therefore retains a higher degree of velocity than a larger bullet of the same form and weight, and therefore travels further and faster. Gravity has less time to act upon it, in a given distance, and therefore it can be fired at a lower angle, or has what we call a lower trajectory, and its accuracy is increased in direct proportion to the lowness of its flight, all other things being equal. ~Best form of rifling still undetermined.~ While the best form, &c., &c., for rifles is not yet determined, there are many points upon which the generality of persons seem more agreed, viz., reduction of bore to about ¹⁄₂-in. in diameter, fewer grooves, shorter barrel, and with increased spirality; at least, one may safely say that ideas seem to travel in this direction. ON RIFLE PROJECTILES. ~Projectiles used in early guns.~ ~Elliptical iron bullets 1729.~ We have learned that out of early Artillery were fired bolts, darts, bombs, stones and (more recently) iron shot. From the harquebus and musket: arrows, darts, quarrels, sprites, iron, and lastly leaden spherical balls. Some assert that the idea of lengthened eliptical bullets was enunciated so far back as 1729, and that good results followed their employment, but it is doubtful whether such really did take place. ~Leutman.~ Leutman, in his “History of St. Petersburgh,” says that “it is very profitable to fire elliptical balls out of rifled arms, particularly when they are made to enter by force.” ~Robins 1742.~ Robins, in 1742, recommended the use of projectiles of an egg like form, (see plate 20, fig. 12), they were to be fired with the heavy end in front, to keep the centre of gravity forward. ~Beaufoy 1812.~