Having got the two lengths of the whole dozen turned into tubes, they proceed to weld the longer length or forepart, by heating it sufficiently for four or five inches, introducing a mandril of the required size to suit the bore wanted, and then beating it into a perfect tube, in a groove on the anvil, of corresponding diameter; heating it again and again, until the joint is closed the whole length. They then proceed with the other eleven foreparts, and advance the whole to that stage before welding on the breech lengths; which are now partially heated by laying on the outskirts of the fire, to be in readiness: they are then closed the same as the foreparts. The end, when about to be jointed, is opened a little on the peam of the anvil, to admit a portion of the end of the forepart; which is introduced as soon as both are in a welding state: the mandril is then introduced, and the joint is perfected, in less time than we have occupied in the description. The other part of the tube is closed, and the barrel is then complete. If, however, the breech part is to be square or octagon shaped, it is not welded in a groove, but on a plain surface. Competition has reduced this department of the trade to a low ebb; thousands of these sort of barrels being now annually welded for about eightpence each: if to this we add one penny farthing per pound for six pounds of iron, we get a forged gun barrel for one shilling and threepence halfpenny. This is certainly a poor remuneration for sweating over a furnace containing from two to three hundredweight of intensely heated coal. The introduction of welding by the rolling mill, will eventually supersede this arrangement; a matter to be regretted only on the score of its answering the purpose of preparing the fire for best welding. Of late years rolling has nearly superseded this description of welding. [Illustration]