The outside of the barrel is next turned in a long lathe, which not only reduces the roughness, but, by a beautiful arrangement of cutting tools, gives it the required substance or “pattern,” for a light or heavy rifle. The grinding of the barrels is effected by means of stones, larger than those used for the sword blades, but in a similar manner, and is preliminary to “filing,” which carries the barrel to the shop, where it is prepared for the lock. [Illustration: Grinding Gun Barrels.] These preparations consist of “chambering,” or making the chamber which holds the pin; “breeching,” or cutting the worm intended for the breech-pin, that helps to hold the barrel to the stock by means of a breech-nail; cutting out the little slice into which the “sight” is to be dovetailed; machining the lump; filing the tail-pin, and making the square lump the proper shape for receiving the lock and stock. We are not a little surprised to learn that every part of the lock is finished by hand, the cock being cut with a die worked by a heavy weight, and the smaller pieces being wrought with forge, hammer, and file. [Illustration: Section of Breech. Section of Lock, &c. Bullet Mould. Nipple Key.] The great art in lock-making is to obtain a perfect spring, and those properly tempered are so elastic that, although when fitted in the lock, the two sides are so close as almost to touch, they will, when released, spread to two inches below the edge of the lock-plate. The lock and barrel are now ready for the stock, which awaits them in another shop, where it has been sawn out of walnut wood, and finished by carpenters’ tools. The barrel let into its groove, and the lock properly in its place, the stock is more perfectly shaped and rounded before “screwing together,” or the addition of the different parts of the “furniture,” heel-plate, trigger-plate and guard, trigger, nose-cap, rod, and bayonet. We are now told that the rifle is “finished,” by which, understanding _completion_, we are not quite prepared to learn that it is to be taken to pieces. We suddenly remember, however, that it is not yet a rifle at all, inasmuch as it has not been rifled. Everything is made perfect before this delicate operation is attempted, in order that no injury may be sustained by the barrel when the complete rifle is again put together. The process of rifling is similar to that of boring, except that a spiral cutter is substituted for the bit. Previous to the reunion of the barrel, the whole work is polished, and the stock stained and finished ready for completion. [Illustration: “Finishing.”] The pistol barrels undergo the same processes as that of the rifle, except that, after being drilled, they are planed, by machines which carry them along a sort of bed under tools that cut them perfectly smooth, and accurately shape the octagonal barrels. These chisels move by means of screws over the entire surface as it is drawn backwards and forwards on the slide.