The invention of the patent wire cartridge is rather the production of a scientific mind than the production of chance; though the invention of General Shrapnell contains the principle, and the perfection attained is but the extension of that principle: namely, the means of projecting a number of bodies of a similarity in size without subjecting them to an extreme jamming by the lateral expansion, and thus allowing each to travel his allotted distance without any of his companions robbing him of his speed by impact. The great peculiarity of the wire cartridge is, that being less than the bore, and having no bottom wadding, the explosive fluid acts all around, between the sides of the barrel and the net, by what may not inaptly be termed the windage, and the shot are thus expelled by a cushion-like force, which does not jam or compress them in the way it is liable to by a wadding forcing it outwards. Here the net is of use to keep the whole in a mass; but you must not suppose the same would be obtained by a charge of shot, without a wadding below. The net opens, after leaving the muzzle of the gun. The introduction of bone-dust is intended for, and answers the purpose of preventing the grains of shot being mis-shaped by the compression: during their passage up the barrel they form with the bone-dust a comparatively solid body, and keep the pellets from impact, thus allowing them to go forth into the atmosphere beautifully round and uninjured; and, as such, more likely to travel farther and stronger. The latter arrangement possesses all the science, as the net can be dispensed with; for it aids the combination but slightly, and in no case more than a moderate quantity of good paper would do. The science of this mechanical construction of projectiles is perfectly in keeping with all the established laws of motion, and more particularly good in thus avoiding the necessity of lateral pressure on the sides of the tube of the gun, the upper end having the means of better resisting the column of air in their progress outwards; for there can be no question but this controls and induces the divergence of the shot in leaving the muzzle. One of the old arrangements, often laughed at, I mean the bell muzzle in old guns, intimates that our ancestors possessed some smattering of science; as the relief in the muzzle of a gun has a tendency, by allowing a gradual expansion laterally, to keep the charge of shot better together: for it is quite apparent that any body severely compressed for a certain distance, expands in proportion when free of that restraint; and the consequence is a tendency to fly off at a tangent, as the friction of a crooked barrel induces a ball to fly in a curve contrary to the bend of the barrel.