ARTILLERY 



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ARTILLERY 



Anti- Air-Craft Guns. The War of the Na- 

 tions brought into use a new type of gun, one 

 for which there had previously been no de- 

 mand. The danger from above, in the form 

 of bombs, did not exist, or was not realized 

 until actual accomplishments showed what an 

 important part aeroplanes and dirigible balloons 

 were to play in modern warfare. The ideal gun 

 to resist aerial attacks, one firing a shell in an 

 absolutely vertical line, has not yet been 

 evolved, the nearest approach being a gun 

 firing at an elevation of seventy-five degrees. 

 Airships could not possibly rise above the 

 range of big guns firing shells vertically. At 

 such an altitude the occupants of the air craft 

 would probably die for lack of air. Anti-air- 

 craft guns are mounted on high buildings, on 

 wheeled carriages or on automobiles, and are 

 capable of rapid firing, rapid adjustment of 

 sights and quick changing of the angle of ele- 

 vation. Machine guns firing rifle bullets are 

 effective against air craft when flying low, but 

 r guns firing one-,' two- and three-pound 

 shells are more to be relied on. 



United States Artillery. In the time of the 

 War of Secession the United States artillery 

 consisted of muzzle-loading "cannon," as they 

 were then called. Improvements, however, 

 have kept pace with, and in some cases antici- 

 pated, those introduced into European coun- 

 tries. In the Spanish War the American artil- 

 lery rendered good service, and at present the 

 gunners of the United States navy and army 

 are as efficient as those of any European power. 

 The 3-inch field gun and mortar, 5-inch siege 

 gun and 7-inch howitzer are the most modern 

 and effective weapons. The forces of Canada 

 are armed with guns similar to those used in 

 the field and horse artillery of the regular 

 British army. 



How Big Guns are Made. The use of steel 

 in the making of big guns is of comparatively 

 recent origin and was rendered necessary by 

 the constant struggle for supremacy between 

 offensive projectiles and defensive armor. As 

 it became necessary to use projectiles of greater 

 power it became imperative to produce a 

 weapon capable of discharging such projectiles 

 with accuracy and with safety to those working 

 the gun. Bessemer steel was one of the first 

 and most important steps in the production of 

 modern weapons of destruction (see STEEL). 

 Other processes have followed by which the 

 metal is still further hardened, enabling it, when 

 forged or molded into the form of a big gun, 

 to withstand the pressure of explosives that 



have steadily increased m power. A modern 

 shell, fired from a gun made only a few years 

 before the employment of hardened steel, 

 would burst the gun and probably do more 

 damage to those firing it than to the enemy. 

 Modern weapons, however, are made to with- 

 stand a pressure of at least twenty tons to the 

 square inch of surface, and bursting is of very 

 rare occurrence. The steel now used is of the 

 carbon type, or that with a certain proportion 

 of nickel added. Steel with an admixture of 

 four per cent of carbon and 0.4 per cent of 

 nickel is now considered the strongest possible 

 combination. Even this material undergoes 

 further hardening processes, such as annealing 

 and oil hardening, which will be later described. 



Forging. The first process is naturally to 

 procure the molten steel. For this the open 

 hearth method is employed (see STEEL). The 

 molten metal is poured into a mold of the re- 

 quired size and allowed to cool. The ingot 

 thus produced is reheated and transferred to a 

 hydraulic press in which it is forged to the 

 required shape and size. The steam hammer 

 with its mighty blows has been superseded, the 

 hydraulic producing greater pressure, amount- 

 ing sometimes to as much as 10,000 tons. Guns 

 of more than 8-inch internal diameter, or 

 bore, are forged hollow over a tube cooled by 

 running water. When the forging is complete 

 the gun is heated again and allowed to cool 

 gradually, usually being placed in warm sand; 

 this process is termed annealing. A further 

 hardening process consists of heating the metal 

 to 1,600 F. and plunging it quickly into a bath 

 of oil. The forged gun is placed on a lathe 

 and the barrel is bored to the required size. 

 The rifling, a series of curves or partial curves, 

 is cut by machinery so delicately adjusted that 

 the cutting may be judged to the thousandth 

 part of an inch. 



The Jacket. The above proceedings refer 

 only to the inner barrel or tube of the gun. 

 Next comes the process of fitting this tube with 

 a jacket or covering to give it sufficient strength 

 to meet its required test. An outer tube is 

 forged of such a size that, when expanded by 

 heat, it will fit over the inner tube. As it 

 cools, the jacket contracts and grips the inner 

 tube as tightly as though both were forged 

 from one piece of metal. The completed gun 

 is again placed in a lathe, when extra bands 

 are shrunk on to strengthen it still further. 

 The gun is then ready for its final testing for 

 accuracy of bore, the breech mechanism is 

 added, and the gun is ready to be mounted. 



