The first state of the barrel is that of a slab of iron which weighs 10 1/4 pounds. This is welded and finished in a building separated from the main building. The first process causes this plate or slab to become a tube; it is then drawn out to the required length, the bore being kept hollow by means of a rod of iron; the breech-piece is welded on by means of a nervously excitable steam-hammer, which strikes a series of blows with uncommon rapidity. The boring is then proceeded with, many and various instruments being used. The outside is next turned, and any extra parts are taken off. The viewing then takes place. This is performed by a skilful workman, who places himself opposite a gas-lamp, or where there is a great light. To this he directs the barrel, so as to bring the light down the bore; he then slowly turns the tube, and is thus enabled at once to detect the slightest deviation from a straight line. Should any irregularities be discovered, the viewer taps the barrel with a hammer until the tube is perfectly true. The rifling of the barrel is then proceeded with. The proving is not the least important part of the process, although it is one which requires the least skill. The barrels are proved in a small room apart from the other buildings. The barrels, before being browned, are laid into stocks fitted for the purpose, and charged with 7 1/2 drams of powder and a bullet; the door of the room is closed, and the barrels are discharged by means of strings which are fastened to the triggers, and which can be pulled from the outside of the wall. Four drams are then discharged as before, and the barrels which have stood these proofs are considered sound. Sometimes there appears a flaw in the barrel, and then powder is added and charges fired, until the barrel is burst. We were informed that such a case had occurred some weeks previous to our visit, and it was not until 20 drams of powder had been used several times, that the desired result was obtained. Our informer stated that he had even then his doubts whether the bursting was not caused in consequence of the bullet not being quite rammed home.
The browning of the barrel is a very delicate operation, and one which must be very trying to at least one of the individuals concerned, for in a room in which the thermometer must stand at about 140 degrees, a man remains upwards of twenty minutes to superintend the drying. Here it is that the mechanic is at last affected by external circumstances. The state of the weather is, in the browning, an important matter. If it should be wet, not more than half as much work can be accomplished as though it were dry. Flaws are more likely to occur during wet than during fine dry weather, and for every flaw, somebody has to be mulcted, for all is contract-work. A very small speck upon a barrel had been detected by the sharp eyes of an the examiner; a chalk-mark against it showed that this would not be allowed to pass; and two-pence-halfpenny was the loss which the man who had imperfectly done his work would suffer for this one flaw.
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