The name of machine guns has been applied to arms which may be regarded as in some respects intermediate between cannons and rifles, since in certain particulars they partake of the nature of both. Like the former, they are fired from a stand or carriage, and in some of their forms require more than one man for their working: in the calibre of their barrels and the weight of their projectiles, they are assimilated to the rifle, but they are capable of pouring forth their missiles in a very rapid succession—so rapid indeed as practically to constitute volley firing. The firing mechanism of the machine gun has always an automatic character, but the rifle has acquired this feature, so that it cannot be made a distinguishing mark: on the other hand, since machine guns have been made to discharge projectiles of such weights as 1 lb. or 3 lb. there is nothing to separate them from quick-firing ordnance unless it be the automatic firing. The idea of combining a number of musket-barrels into one weapon, so that these barrels may be discharged simultaneously or in rapid succession, is not new. Attempts were made two hundred years ago to construct such weapons; but they failed, from the want of good mechanical adjustments of their parts. Nor would the machine gun have become the effective weapon it is, but for the timely invention of the rigid metallic-cased cartridge. Several forms of machine guns have in turn attracted much attention. There is the Mitrailleur (or Mitrailleuse), of which so much was heard at the commencement of the Franco-German War, and of whose deadly powers the French managed to circulate terrible and mysterious reports, while the weapon itself was kept concealed. Whether this arose from the great expectations really entertained of the destructive effects of the mitrailleur, or whether the reports were circulated merely to inspire the French troops with confidence, would be difficult to determine. Our own policy in regard to new implements of war is not to attempt to conceal their construction. Experience has shown that no secret of the least value can long be preserved within the walls of an arsenal, although the French certainly apparently succeeded in surrounding their invention with mystery for a while. The machine gun, or “battery,” invented by Mr. Gatling, an American, is said by English artillerists to be free from many defects of the French mitrailleur. In 1870 a committee of English military men was appointed to examine the powers of several forms of mitrailleur, with a view to reporting upon the advisability or otherwise of introducing this arm into the British service. They recommended for certain purposes the Gatling battery gun. [Illustration: FIG. 105_b_.—_The Gatling Gun.—Rear View._ ]