Colonel Prejudice has invented a vastly improved description of gun; another guess is made, and so different forms of guns are multiplied. Can there be a more striking illustration of this than the one which took place during the late Crimean war? It was boasted that the whole human race might be exterminated by the new invention; but the “Lancaster gun” turned out to be most unscientific in its construction, and most eccentric in its action. Had such a thing as scientific knowledge in gunnery existed among the artillerists of the day, such a monstrosity would have been buried soon after its birth; instead of being allowed to squander large sums of money at every discharge, and then at last to become a “Whistling Jemmy” for our bluejackets to laugh at. The form of cannon no doubt exercises a vital influence over their durability; bad form and imperfection of material combined, tended to produce the rapid destruction of our guns during the late important struggle. The gun which has been experimented with to the greatest extent, and which has withstood all trials successfully, is a Russian fifty-six-pounder; taken, I believe, at Bomarsund. In this gun there are two great peculiarities; the shape, as will be seen in the diagram, differs from all our own guns: it is a “chambered gun,” and the metal is taken away from the outside precisely as the contraction increases on the inside thus giving an equal thickness of metal in every part, of the arc (see page 114). In contrast with this, we give a cut of our 8-inch gun, which most nearly resembles it as a chambered gun (see page 114). The reader’s attention is especially directed to the dissimilarity in the distribution of the metal in the two guns. The want of uniform thickness of metal in our 8-inch gun must be sufficient to convince any one that, if the Russian gun be properly constructed, the principle of ours must be radically wrong. That such is the case, indeed, I cannot doubt, the Russian gun having undergone such a test as would have destroyed six of ours. The gun has since been made two inches larger in the bore, and even oval-bored, for firing shells, which should alone be enough to destroy it; and yet with all this the gun remains perfect. The gun which most nearly resembles this is our English carronade; and that these guns have some important principle in their shape is proved by their great durability under all trials; and I believe that the tests to which the carronade has been subjected have been more severe than that of any other piece in the British service. There have been many shrewd conjectures as to the cause of this durability; one of these was very pungent, viz., “the invention was not by one of the cloth.” An examination of the drawing of the 68-pounder carronade will enable the reader to perceive the great similarity between this and the Russian gun before spoken of (see page 114). [Illustration: 68-pound carronade.]