New principle--Improved rifles--Useless inventions--Scientific principles of gunnery: 1. The explosive power and its velocity. 2. The retarding agents. 3. Construction of the tube. 4. Form of projectile-- Robins’s theory--Hutton’s experiments--Suitable velocity the germ of the science--Author’s experiments and their results--Penetrating power of bullets--Resistance of the atmosphere--Friction detrimental-- Construction of the tube--The Cylindro-conoidal form best suited for projectiles--Jacob’s and Whitworth’s bullets--Lengthened projectiles tend to burst the barrel--Amount of heat needful to explode gunpowder --Advantage of unglazed powder--Percussion powder--Best form of nipple (with cuts)--Propellant velocity the grand desideratum--Why short guns shoot better than long ones--True science of gunnery--Cause of guns bursting--Mr. Blaine’s difference of opinion with the author on explosive force--Shooting powers of different gun barrels--Tables of strength and pressure--Colonel Hawker’s axiom--Mr. Daniel’s remarks on shot--Duck and swivel guns--The wire cartridge--Bell-muzzle guns--Mr. Blaine on long barrels--The just medium--Belgium guns will not stand English proof--Cause of their inferiority--French gun-makers behind the age--Author’s notes on the “Specimens by French Gun-makers at the Paris Exhibition”--On recoil in shooting--Causes and experiments--Mode of determining the size of shot suited to the bore of gun--Mr. Prince’s double gun 257 CHAPTER VIII.--THE FRENCH “CRUTCH,” OR BREECH-LOADING SHOT GUN. Breech-loading fire-arms unsafe and inferior--Objections specified-- Trial of breech-loading against muzzle-loading guns--Danger from using breech-loaders--Excessive recoil 329 CHAPTER IX.--THE RIFLE.