The use of old horse-shoe nails is of a date nearly coeval with the use of small fire-arms. These nails are made from rod iron of the best description; and the hammering cold, or tempering the nail, so benefits and condenses the iron as to improve it greatly. The method in use until a late period, was to fill and force into an iron hoop, of six or seven inches diameter, as many stubs as it would contain, to weld the whole, and draw them down to a bar of such dimensions as might be required. Modern improvement, however, has shown the advantage of cleansing the stubs perfectly by a revolving drum, and then fusing and gathering them into a _bloom_ on the bed of an air-furnace. Thus a body of from 40 to 50 lbs. of melting iron can be obtained at one heat; a matter of economy and necessity, where large quantities are required, besides possessing the superior advantage of having the whole mass equally heated: this cannot be done by the old hoop method, as the surface must be frequently burnt before the interior is at all in a welding state. Experience taught the late Mr. Adams and his brother George--who still manufacture some of the best gun iron in the world--that the stub iron alone was insufficient; for even then (forty years ago) the absurdity of imagining that no barrels were or could be good without being soft, was understood and acted upon by them. They introduced at first one-fourth of steel to three of stubs; this having been found highly advantageous, the prejudices of the gun-makers were gradually overcome, or left in abeyance from ignorance of the introduction. It is a fact, that as late as 1842, when I issued my former work, men who had been all their lives _gun-makers_ (by courtesy) actually refused to believe that any steel at all entered into the composition of the best barrels; and several whom I know perfectly well, ordered the factors with whom they dealt “to be sure to send them no barrels with steel in, as they did not wish their customers’ hands to be blown off.” Charcoal iron has, up to this day, been the only stub twist barrels they (and we believe two-thirds of the provincial makers also) have ever been served with. Reason with these men, and they will snappishly tell you, “We pay the best price, and we ought to have the best: we don’t see that our neighbours have any better.” On one occasion of my calling upon one of the first provincial gun-makers in the kingdom, the subject of barrels was adverted to--“An excellent work that of yours, I dare say; but, sir, you have done a deal of harm: it is wrong to let gentlemen know too much; they give you far too much trouble: they get too knowing.” These, and such like observations, are the only thanks I ever received from the generality of the gun trade. There are, however, some enlightened men who, understanding the subject, have appreciated my motives; but by far the greater proportion have done the reverse, asserting “that I had told them nothing but what they knew before.”