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.
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 Of late years rolling has nearly superseded this description of welding.
They now commence the welding of twist barrels. Spirals that are intended for the breech end, are heated to a welding heat for about three inches, removed from the fire, and jumped close by striking the end against the anvil. Again they are heated, and again jumped, to ensure the perfect welding. They are then beaten lightly in a groove, to make them round. The neatest part of the process consists in the joining of the points of the two rods, so as to make the barrel appear as if it had been twisted out of one rod. The ends of the two rods are a little detached, brought from the fire, and applied to each other; a gentle tap is then given, and the union is perfect in an instant. The rapidity and dexterity with which this is accomplished, ought to be seen to be duly appreciated. This trouble is only taken with the best barrels. In the manufacture of barrels of an inferior description, the ends of the rods are cut in a sloping direction, and when welded together, become quite square at the part where the pieces are joined. In a finished barrel the points of junction are easily recognised. By tracing the twist, a confusion will be found to exist for about an eighth of an inch, every six or seven inches; and from this appearance you may conclude that, for a barrel so joined, the welder had not the best price. Having joined the whole of the spirals, three inches are again heated to a welding heat, the mandril is introduced, and the tube hammered, in a groove, to the size required. This operation is repeated until the whole length is finished.
Then follows hammer-hardening: that is, beating the barrel, in a comparatively cold state, in a groove, with light hammers, for the space of half an hour. This is a most important part of the process. It closes the pores, condenses the texture of the metal, compresses a greater substance into less bounds, increases greatly the strength of the barrel, and renders it more elastic. Yet this is seldom done, unless specially requested; and then a gratuity is, of course, expected either in money or beer. A few pots of the juice of Sir John Barleycorn will infuse more strength into your barrels than you could purchase for ten times the amount in money; as they have the effect of making the hammers descend with increased velocity.
If all barrels were hardened in this manner, their shooting powers would be increased, and they would not be so liable to burst in the hands of the sportsman. This, however, cannot be done, unless the purchaser either sees it done himself, or has it done under the superintendence of some person on whom he can depend. The Birmingham workmen, if well paid and well looked after (to counteract the bad habits they have acquired from being employed in the manufacture of so large a quantity of goods of an inferior quality), would produce an article superior to any that could be produced, at the same cost, in any other part of the world.
The Belgian welders do their work at considerably less cost in coal than our English workmen. Coal, it is well known, is very dear in Liege, and necessity may have taught them the extreme of economy both in the size of their fire and the duration of it. They effect this by adding to two-thirds of coal, beat into dust, one-third of clay; the latter is mixed with the coal by being put into a wooden barrel, the two well stirred up together, and the water drained from it. Even this mixture is used sparingly: the fire being scarcely larger than might be held in the two hands, while with us little short of two hundredweight suffices: which is unquestionably a great and unnecessary waste. True the Belgian does not get through the great quantity of work the Englishman does by having “a great many irons in the fire” at once; but he certainly does it well and clean: the quantity of earthy matter in the Belgian’s fire gives a great heat, which also is retained longer; and it is also free from any excessive quantity of particles of charcoal.