GUNNERY 307 G. Armstrong & Co. are now (1879) experimenting with field guns, both muzzle and breech-loading, yielding veloci ties of 2000 f. s., and no doubt a fresh development of the new principles of air-spacing and chambering (already initiated in the Royal Gun Factories) is at hand (see GUNMAKING). The history of the progress of siege guns would be in a Siege great measure a repetition of that of the field artillery, guns. Briefly, the smooth-bored siege train of cast-iron 18-pounders and 8-inch howitzers was replaced in 1859-63 by one com posed of 20-pounders, 40-pounders (figs. 25-28), and 7-inch rifled breech-loading pieces, with certain howitzers which aomHcrnintcitnta - . I4-6ZS. _ _i f.5-1 _ __ J- - J3.-SS- - -i!S|.9 - FIG. 25. 40-pounder Armstrong Rifled Breech-loader. never earned adoption. Subsequently the breech-loaders have been gradually ousted by 25-pounder, 40-pounder, and 64- pounder muzzle-loaders, with 8-inch, 6 6-inch, and 6 -3-inch howitzers, new patterns of which latter pieces have just passed their early trials. The 64-pounders were introduced in 1864. For naval purposes the calibre was chosen so that FIG. 26. 40-pounder Breech Screw. 32-pounder round shot could be fired from it on emergency. The 40-pounders are stronger, and fire much heavier charges than their breech-loading congeners. The 25-pounder was introduced in 1874 to supersede the 20-pounder breech loader for light siege trains, and as a gun of position. Ever since 1853 experiments have been carried out by the Eng- FIG. 27. 40-pounder Vent FIG. 28. 40-pouuder Vent Piece. Piece (section). lish and other nations for the improvement of mortars and howitzers, first in a smooth-bored and then in a rifled state. These experiments are still in progress, and it can not be said that the art of throwing heavy shell at high angles has as yet arrived at perfection. In 1872 short pieces throwing shells of 180 fi) and 64 Ib were adopted, but recently longer and more powerful shell-guns have been tried, throwing heavier projectiles with greater accuracy. In these new pieces polygroove rifling with gas-check rotation affords a hope that the necessary precision may be attained. The " converted guns " must not be passed over, since Con- they are largely employed to arm our land fronts and to verted provide cheap and efficient pieces for practice by the reserve uns - forces. When first elongated rifled projectiles were intro duced, a great many methods of strengthening the old cast iron ordnance were proposed. The most satisfactory was that put forward by Palliser, and consisted of lining bored- out cast iron shells with wrought iron tubes. Some of the smaller men-of-war carry these pieces, but the great majority are used only for the secondary purposes above mentioned. The 32-pounders of 58 cwt., and the 8-inch shell-guns of 65 cwt., have thus become 64-pounders, and the 68-pounder of 95 cwt. has become an 80-pounder. Important as are the land-service pieces of the army to England, yet, viewing her naval supremacy as one of the chief sources of her greatness, we must consider heavy ship and coast-defence ordnance to take the first place in modern gunnery. The contest between guns and armour has now continued with scarcely any intermission for upwards of twenty years, during which time the armour has increased in thickness from 4 to 24 inches, and the guns from 68- pounders to 2000-pounders ; that is, from the most power ful of the old cast-iron smooth-bores to the 100-ton gun. The first armour-piercing rifled guns were the 7-inch Arm- Anno strong breech-loaders, but their supremacy was of short pierci duration. They were the heaviest made on that system, 8 uns> and were speedily succeeded by far more powerful muzzle- loaders. In 1867 8-inch and 9-inch guns had already been introduced. The 9-inch "Woolwich rifled gun of 12 tons was tried in competition with the xv-inch American smooth-bore, which weighed nearly half as much again, against armour. The British piece gained a decisive victory. In 1868 it was decided to introduce a 10-inch gun of the same character. Since that time progress has been con tinual, and the latest productions of the three great gun- producing establishments of the world are the 71-ton steel breech-loader, recently tested, of the German maker (Krupp), the 80-ton muzzle-loader of Woolwich, and the 100-ton muzzle-loader of the Elswick firm (Sir W. G. Armstrong & Co.). Tables IV. and V. show all the principal rifled guns in the land and sea services of Great Britain. It has always been an object with the authorities to assimilate the guns of the two services as far as their respective requirements will permit, and so to avoid multiplication of stores at the numerous home and foreign stations where supplies are
made ; but still it will be observed that considerable differ-