The iron made from stubs and steel, and plain fibrous steel, is invariably rolled down into rods of 6-16ths broad, forming a spiral, as below. [Illustration] A proper attention to the fineness of the spiral will always enable an amateur to detect any attempt at imposition. The spiral formed from the rod of charcoal iron has a somewhat different appearance; but in cases where it is intended to supply the place of the real stub iron it is of corresponding dimensions, and in general very difficult to detect without a very intimate knowledge indeed of the nature of iron. When honestly intended, it forms a similar spiral to the accompanying one. [Illustration] The wideness of the twist, or the angular direction of the fibres, will enable the most uninitiated to recognise a barrel made from threepenny skelp iron: the very few welds required, is one cause of the cheapness of barrels made from it. Judgment may be formed of it from the following representation. [Illustration] Twopenny, or Wednesbury skelp is coarser in the spiral still, and running so angular as not to be very difficult to detect. [Illustration] All iron formed in spirals, as a matter of certainty, forms _twist barrels_--the parties whose use they are intended for, seldom know or care for anything further than having “a twist barrelled gun.” The advantage of _sham damn_ iron being twisted is all imaginary: if used at all, it may be twisted; but those who value their safety would consult it best by tying a large stone to such a gun and sinking it fathoms deep. But to satisfy those who may fancy such things, I give a woodcut of the spiral ready for welding. [Illustration] The spirals being thus formed, the welders commence their day’s work. The batch consists of a foreman, one on whose skill all depends, and two subordinates, whose duty it is to blow the bellows, strike, &c. They proceed to weld probably a dozen long common barrels for the American trade; which are generally composed of the inferior iron mentioned before, rolled into two lengths of different thicknesses. These skelps are heated, and beaten on a groove until they form a tube half closed. They are then heated again, and closed with one edge over-lapping the other; as a brazier would over-lap the edge of a tin pipe, for boys to blows peas with.