Page:Popular Science Monthly Volume 88.djvu/530

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��Popular Science Monthly

��the increased number that we are per- mitted to mount on any ship of equal displacement."

But we have not rested here. In August, 1 914, a type of sixteen-inch gun forty-five calibers in length was tested. This gun fulfilled the expecta- tions of its designer. It is probably the most powerful gun in existence to-day. Some day it will be mounted on our battleships.

A Modern Fourteen-inch Gun Is Better Than Sixty Thousand Muskets

The projectile of the modern four- teen-inch naval gun starts at a velocity of about two thousand six hundred feet per second. Its weight is one thou- sand four hundred pounds. Compare this with the weight of a musket-bullet ■ — one hundred and fifty grains — which starts with a velocity of two thou- sand seven hundred feet per second. Rear-Admiral Bradley A. Fiske has made a very interesting comparison of the striking energy of the two. "After the bullet has gone, say five thousand yards, its energy has fallen to zero, while the energy of the fourteen-inch projectile is nearly the same as when it started. While it would be truthful, therefore, to say that the energy of the fourteen-inch gun within five thousand yards is greater than that of sixty thousand muskets, it would also be truthful to say that outside of the five thousand yards millions of muskets would not be equal to one fourteen- inch gun."

The high-powered, long range fifteen- inch guns mounted on modern dread- noughts of the Queen Elizabeth type have made it necessary for the United States of America to consider its coast defenses. Remember that the Queeji Elizabeth can fire her great guns accu- rateh' at a range of twenty-five thousand yards, and that our best coast defense guns could not touch her, partly because they are mounted on obsolete disappear- ing carriages which do not permit an elevation of more than fifteen degrees, and partly because the guns on dread- noughts of the Queen Elizabeth type represent the very latest advance in ordnance. Even our newest fourteen- inch coast-defense guns, of which fi\e

��were completed last year, have a maxi- mum range of only eighteen thousand yards, which has been increased to nineteen thousand three hundred by enlarging the powder chambers.

Some idea of the power of a modern fourteen-inch coast defense gun may be gained when it is stated that its sixteen hundred pound projectile gun will drill through nearly twenty-three inches of the best quality of armor at one thou- sand yards and through ten inches at one thousand nine hundred yards. The fourteen-inch coast defense gun made at Watervliet Arsenal, weighs when finished one hundred thirty-eight thou- sand pounds, costs fift^'-five thousand dollars and is wound about with thirty- seven thousand pounds of wire.

Realizing that even this mighty weapon is too feeble an opponent for a Queen Elizabeth, we are beginning to build sixteen-inch coast defense guns. They are the largest and longest in the world. Unfortunately only two of them have been built, and these are intended for Panama, to protect the canal.

Shots That Cost One Thousand Dollars Each

At an elevation of forty-three degrees, such a gun will have a range of twenty- one miles. That is about the distance which many suburbanites have to travel in an hour in order to reach their offices in New York city. The piece alone weighs one hundred twenty-seven tons. The shell, two thousand four hundred pounds, can pierce twenty-one inches of armor 2.8 miles. The powder charge is four hundred pounds. The shell and powder alone cost one thousand dollars.

The most commendable feature of our fortifications are our mortars. They are first-class and their high angle fire is as good as there is anywhere. Our twelve-inch mortar fires a shell weighing one thousand and sixty-four pounds and has a maximum range of twenty thou- sand yards.

Our coast defenses are in reality harbor defenses. Of our five thousand miles of coast line not more than three hundred are under potential protection of fortifications. The greater part of our seaboards is absolutely undefended at the present time.

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