Читать книгу The Complete English Wing Shot онлайн

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It is not quite certain in which battle was first employed gunpowder—a fact which indicates that it did not do much for its side. It appears to have been the guns that were weak, not so much the powder, which was probably very much the same when used by Henry VIII. as black powder is to-day.

It is, moreover, not certain that guns were any better at Waterloo than they had been in the time of Elizabeth. The reason for this was the want of good metal. It is a known fact that thickness of metal becomes useless after a certain point is reached, so that iron and brass guns could not be made to take enormous charges of powder and heavy shot without bursting. This might have been done by making them very long and using a slow burning powder, but that way out never seems to have been thought of until recently. The reason modern big guns will take such enormous pressure as the big charges behind heavy shells give, is, first, that they are made of steel, and second, because the tension on the steel internally and externally is equalised by a very clever method. The guns are built up by being bound in wire in a heated state, so that when this wire cools it contracts the internal tube as it contracts itself. This being the case, when an explosion takes place in the finished gun, it has to overcome the wire contraction on the outside of the gun before the internal tube can begin to expand beyond its natural size. That is how a thickness of metal is made serviceable, and prevents a bursting of the internal surface before the external bigger surface is strained. In other words, the pressure is resisted equally all through the thickness of the walls of the barrel. This has entirely revolutionised big gunnery during the last thirty years, and has enabled ships of war to hurl 800 lb. shells through the armour of enemies who are hull down beyond the horizon.