Page:Popular Science Monthly Volume 91.djvu/863

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Popular Science Monthly

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At a 70-mile range the gun's possible destructive area is 15,386 square miles; at 100-mile range, 3 1 ,400 square miles. We can imagine its projectile bounding over our highest mountains with ease

��chloride of nitrogen. The second shell would be aimed at the same place and fired as quickly as possible to get the same atmospheric advantages, whereupon it would begin after landing to vomit in- numerable small shells containing osmium and hydrocyanic acid, cyanogen, etc. The silent death produced by osmium would make an ordinary graveyard tame and commonplace; for the osmium that

��can be piled on a ten cent silver piece will kill 1,000 persons. I have devised a shell which would contain enough of that poisonous metal to kill 300,000 people and 700,000 persons, respectively, allowing the usual 10% for failures, etc. The gas would travel in waves from a central point. The crest of each wave would be a terrible compression, and the bottom of each wave a fearful vacuum.

��What's Wrong with the Big Gun

��MR. BUNNELL, the author of the foregoing article, is one of the few laymen who has definitely attacked the problem of the big gun. He is an artist with an imagination, as his pictures and his article prove. We gave him space in the Popular Science Monthly to set forth his ideas. And now the Editor shall proceed to give his view of them.

The size of a gun cannot be increased without paying the price. The weight of a heavy gun, the projectile and the powder charge vary almost directly with the cube of the diameter of the bore. Hence a small increase in diameter means a very large increase in power. For example, a twelve- inch gun fires a shell which is about seventy-five per cent, heavier than that fired from a ten-inch gun; a fourteen-inch gun fires a shell about sixty per cent, heavier than that fired from a twelve-inch gun; and a sixteen-inch gun fires a shell half again as heavy as that fired by a fourteen-inch gun. A sixty-inch gun would be at least two hundred and fifty feet long; its shell would weigh about sixty tons; and the charge would be about twenty tons of powder. The weight of the gun itself would approximate that of the old battleship Oregon ; the carriage would weigh twice as much.

Now it must be admitted that such a gun could be built. But are the existing facilities adequate for handling such an enormous mass in a single unit? We doubt it.

Consider the mere matter of machining the cast- ing. The lathe to bore and rifle the gun would be not less than five hundred feet long — twenty times the length of any lathe ordinarily seen in a machine shop, except lathes built for very special purposes.

How would the completed gun be transported? Transportation by rail would be impossible in many places.

No doubt bigger guns than those we have now can be built. But the ordnance expert and the

��military strategist asks himself: Is it worth while spending the necessary time, energy and money?' To justify its existence a huge gun such as that which Mr. Bunnell proposes would have to ac- complish amazing results. In judging these results such factors as probable life, range, accuracy, rapidity of fire, character of the target and de- structive effect of the projectile would have to be considered.

As the destructive effect of the projectile is ap- proximately proportional to the weight, this is usually not a determining consideration, provided the projectile can destroy its probable target, which for heavy guns is usually considered as the most powerful battleship afloat or contemplated.

The range does not increase greatly with the caliber. At the usual maximum elevation the range of a sixteen-inch gun is only about a mile more than that of a similar ten-inch gun. A sixty-inch gun would have an appreciably greater range than a sixteen-inch gun, but not great enough to be a de- termining factor. The accuracy of fire would also not be appreciably greater. As a projectile not much heavier than the heaviest now in use could destroy anything now known or contemplated, the factors which would determine whether or not a sixty-inch gun should be built would be probable life, rapidity of fire and difficulty of construction.

The life of a gun decreases rapidly with the caliber; probably a dozen rounds fired from the Bunnell gun would mark the duration of its accuracy life — not enough to insure the destruction of a single target. With the best gunners the hits made are limited by accurate observation of fire, by the natural disper- sion of shots, and in the case of ships, by unexpected changes of course.

The increase in size of guns has been a slow evolu- tion. It is not likely that we shall suddenly leap to a titanic weapon. — Editor Popular Science Monthly.

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