“Swaff iron forging” is a profitable branch of forging carried on in Birmingham under the above title. It is a metal which is composed of iron and steel filings, chippings of breeches, pieces and cuttings of the ends of the screws, lock-plates, cocks, the rough borings of barrels, and all other small scraps found in gunmakers’ and other workshops. These are collected by the boys in each shop, and when they have accumulated, are sold to the “swaff-forger,” the proceeds being considered as drinking money. They are forged into bars of iron by attaching them together and immersing them in diluted sulphuric acid; then, after draining it from them again, and placing a large iron pan full in a hot situation, they become cemented together by the action of the oxide. The compound is then taken from the pan, by turning it upside down, and is put into an air-furnace heated to a welding heat, being thence removed and beaten into a bar: three men with light hammers beating it as quickly as they do in welding a gun-barrel. This iron is sold to the gun-work forgers, for the forging of the patent breeches, lock-plates, furniture, and other parts of the gun which they think worthy of good iron; but since cheapness has become so much the order of the day, the use of this iron is confined to the forging of best gun-work, cast iron being thought quite good enough for common gun-work. CHAPTER V. GUN-MAKING. In this chapter I shall briefly describe the process of the manufacture of guns of all qualities, commencing with barrel-welding; which, in importance, is inferior only to the _quality of iron_ in the routine of good gun-making.