Note 8 — Chapter IV · ON THE MANUFACTURE OF IRON FOR GUN BARRELS.

Dr. Ure falls into an error in describing the process of barrel boring: he says “the barrel is first properly annealed, and allowed to cool gradually,” &c. The barrel-maker that would take such a proceeding with a barrel of ours should never do so to another. The Doctor ought to have pointed out the evil tendency of this. We never saw it done, and we doubt much whether he did, though we have heard of the practice, which induces us to notice it, but the Doctor describes it as a necessary proceeding.