This principle is to be seen embodied in another interesting old weapon which has been in the custody of the war department since 183o, and is at present housed in the Rotunda at Woolwich. When it was first made cannot now be ascertained. In it are three rows of barrels, 11 in the middle row and ten in each of the others. All are fixed, and the alignment and elevation are practically the same for all. The barrels are over 44 in. long, ,75 in. bore, with i t grooves, twisting one turn in 3o inches. In rear of the barrel and clamped thereto is a plate on which are mounted chambers for each of the barrels. In rear of these chambers was a combus tion box, with which each chamber was connected. This was charged with powder. A percussion cap, mounted on a nipple, when struck by a large hammer under the influence of gravity, ignited the powder in the combustion box and so ignited the powder in the barrel chambers, thus firing all 31 charges simulta neously. An accessory is a machine for loading and charging the plate of chambers. During the early half of the i8th century similar weapons were used in France.
In the same museum is a rifle battery, designed by Sir J. S. Lille, and made in 1854. It consists of two rows of six barrels one above the other and some 6 in. apart in each row. In rear of the barrels are cylinders, similar to the cylinders of the modern revolver. The cylinders in the top row contain ten chambers, and in those of the bottom there were twenty. Each chamber is provided with a nipple for a percussion cap. In rear of these cylinders were rods, on which were mounted hammers for each barrel. On rotating these rods by means of crank handles, the cylinders were caused to revolve, and the hammers fell in succession, starting from the right. This weapon was designed at the time of the Crimean War, but it is not known if it was ever employed in the field. From the foregoing it can be seen that a stage had been reached when a limited number of rounds, fired in .rapid succession or as a volley, could be easily arranged, but the problem of rapidly reloading the discharged barrel was ever present, and so precluded the pos sibility of continuous fire. This great limitation to the utility of these weapons lasted until a system of loading them at the breech instead of the muzzle was introduced. Meanwhile, consequent on Forsyth's invention of the percussion cap in 1805, developments in ammunition had taken place. Gustavus Adolphus of Sweden in the 17th century had caused the gunpowder, which had hitherto been carried in flasks or bandoliers, to be made up into cartridges, which soon developed into the complete cartridge with bullet, charge and percussion cap all in one and contained in a paper case. Such cartridges, rough as they were, lent themselves to em ployment with breech-loading mechanisms, and in 1838 Dreyse embodied such a system in the Dreyse needle gun.
This gun was employed in the American Civil War and later the .45 Gatling was adopted by the British navy. With it a rate of fire of about 600 rounds per minute could be obtained. Its ac curacy, however, could not have been of a high order as it is on record that at Gibraltar, 18 men selected from an infantry regi ment, and armed with the single-loading Martini-Henry rifle, were able to make a better score on targets in a given time than a Gatling gun skilfully handled by 18 blue-jackets. An improved system (Accles) of feeding the gun was later invented, which made possible a rate of fire of 107 rounds in 21 sec. This improved system was produced too late for it to be adopted in the British service, which by that time was committed to other designs.
In Europe, the first machine gun to attract general attention was the Montigny Mitrailleuse, introduced into the French army just prior to the war of 187o. The French, disappointed with their shrapnel in the Italian War of 1859, desired a weapon, the pro jectiles from which would carry to ranges which the infantry, and the artillery firing case shot, could not reach. These guns were attached to batteries of artillery, and in their final form re sembled outwardly an ordinary field gun with a wheeled carriage, limber and four-horse team. This mitrailleuse consisted of 37 rifle barrels, fitted in an outer casing, the whole revolving round a common axis. The cartridges were carried in perforated plates To load the gun these plates were placed in grooves and locked in the breech, which was then forced home, each cartridge enter ing one of the chambers. The gun was fitted with a crank handle, which, when turned, revolved the barrels and fired each of the cartridges in succession, all 37 being discharged in one revolution.