The barrel is welded and finished in a separate factory. The piece of metal out of which the gradually tapering tube is ultimately fashioned seems to bear no relation to such a form. You see the smith take a small plate of quarter-inch iron, about a foot long by a few inches wide, heat it to a welding heat, and then place it between the lips of a rolling mill, with grooved instead of flat rollers, and in an instant it comes out a tube. It has next to be drawn out to the requisite length and tapered, which is done by passing it through a series of mills, each succeeding one being grooved smaller than the preceding. The bore is kept hollow during the operation by a central iron rod. The breech piece is welded on by a single blow of a steam-hammer, and the process of turning the bore begins. Four barrels are acted upon by one lathe, and the first operation is performed in fifteen minutes. Only a slight cutting is made each time, and the barrel has to be submitted to the action of many different boring instruments until the exact size, ·577 of an inch, is attained. The outside is now turned, the tool taking off the superfluous metal in one continuous ringlet of iron.
It now undergoes the most delicate process of all, that of being "viewed." The viewer, who is a highly-skilled workman, with an exceedingly accurate eye, puts himself opposite a gas-lamp, about thirty feet distance, and which has a dark shade on its upper side. Towards this object he directs the barrel so as to bring the dark edge half-way across his sight as he looks through the bore. By this device he is enabled to direct a ray of light with a defined edge down the tube, and by turning the barrel round, instantly detects the slightest deviation from the straight line. As the smoothest-looking sea is discovered to be a mass of dimpling ripples--(the Greek poet's "infinite laughings of the sea")--when the setting sun throws a golden shaft across its bosom, so the mathematically straight lines of light gauge the inequalities of the rifle bore in a more exact manner than any instrument that has yet been invented. When any irregularities are discovered, the viewer taps the barrel with a fine hammer on a small anvil, and repeats the operation until the tube is perfectly true. Upon this depends the correct shooting of the gun, inasmuch as the least crook near the end of the bore would send a bullet far on one side of the mark long before it had attained the full range of 800 yards, to which the Enfield rifle is sighted. The rifling of the barrel in three groves is performed by fixing it in a lathe, and driving the cutter through it in a spiral direction.