Definition of the term--Modern field gun--English artillery behind the march of science--Official obstacles to improvement--Various kinds of British artillery--Table of measurements, and range of iron ordnance--Brass guns--Their peculiar property--Firing of brass and iron guns compared--Range of brass ordnance--Paixhan guns--Traversing beds for ship guns--Ranges of Paixhan guns and howitzers--Mortars-- Their uses and varieties--Monster mortar at siege of Antwerp--Table of English mortar practice--Carronades--Table of weights of guns and shot --Causes of Recoil--Guns of our ancestors--Metal required in rear of the breech--Results of Hutton’s experiments--Weight in fore-part of gun injurious--Firm base for a gun essential--Leaden bed for mortars suggested--New materials desirable for projectiles--Mr. Monk’s gun unequalled--Principle of its construction--Wilkinson’s opinion--Waste of explosive force in ordnance--The propellant force should be accelerative--This attainable by a proper granulation of powder-- Government powder--Gunnery only in its infancy--Compound shot--Lead better than iron for cannon shot--Expenditure of shot at sieges of Ciudad Rodrigo and Badajos--Hutton’s experiments--The shrapnell shell--Improvements in gunnery--The Greenerian rifle--Dangerous inefficiency of English artillery--Best metal for cannon--Increased range destroys guns--Cause of mortars bursting--The Lancaster gun-- English cast-iron inferior--Mallet’s monster mortar--Wrought-iron unsuited to large guns--Reason why--Shaft of the _Leviathan_--New method of welding iron shafts--Railway carriage axles--Nasmyth’s monster cannon--Light gun-barrels stronger than heavy ones--Brass guns inferior to cast-iron--Defect of hoop and stave gun--Form and dimensions of Mallet’s monster mortar (with engraving)--Cause of deterioration of English cast-iron--Russian cast-iron more durable, and why--Krupp’s steel gun--Laminated steel gun-barrels--Captain Dalgren’s improvements in American ordnance--Russian guns--Reinforce rings and trunnions objectionable, and why--Rifled cannon essential-- Range of steel rifled cannon--Best form of gun--Professor Barlow on the strength of iron--Our artillery not constructed on scientific principles--Russian 56-pounder, English 8-inch gun, English carronade, Monck’s 56-pounder, and 10-inch gun (with cuts)--Land and sea service mortars (with cuts)--Joseph Manton’s rifle cannon--Projectiles for rifled cannon--Rifle rockets--Mr. Whitworth’s improvements in rifled guns--His polygonal projectile--Experiments with Mr. Armstrong’s field-piece--Increased range and accuracy of rifled cannon with elongated projectiles--Table of comparative range of smooth-bored and rifled cannon--Shells for rifled cannon--Spiral motion of projectiles from smooth-bored guns--Breech-loading cannon useless and unsafe 58 CHAPTER IV.--MANUFACTURE OF IRON FOR GUN-BARRELS.