Artificial failures can easily be made by filing round the base of a cartridge so that it is torn off when fired; by loosening a bullet in a cartridge, by slightly flattening a cartridge so as to cause it to jam in the chamber, by wedging a cartridge in the belt, by introducing a blank cartridge, and by repacking the asbestos with dry packing. It will be found that by making two or three such jams every time the gun is taken out to fire the detachment will soon become expert in recognising and remedying failures. The men should be taught that failures may be divided into two classes, viz. _avoidable_ and _unavoidable_. The occurrence of an avoidable failure should be looked upon as a disgrace to the firer. The _unavoidable_ failures so seldom occur that they are negligible. The _avoidable_ failures are those due to (1) Fuzee spring adjustment. (2) Want of oil. (3) Dirt. (4) Want of water. (5) Bad packing. (6) Damaged ammunition. (7) Faults in feed due to badly filled, new, or damaged belts. Each machine gun will be found to work best with a certain weight of fuzee spring which can only be found by trial, and this weight will change from time to time as the gun wears. The machine gunner cannot be considered fit for further training until he has become so familiar with his gun that he can instantly tell by the sound if it is working at its best; just as a chauffeur knows at once if his engines are running perfectly, and can instantly detect the slightest defect and make the necessary adjustment of the spark, petrol, or oil to ensure smooth running. The unavoidable failures are so few and rare that they will seldom be met with, and can be quickly remedied, except the breaking of an important part. Failures due to defective ammunition are extremely rare provided ordinary precautions are taken to avoid placing damaged cartridges in the belt. A breakage in any part of the lock can be remedied in a few seconds by substituting the spare lock which should always be _on the gun_ in action. The breaking of any other part of the gun will be an accident of rare occurrence and, provided the gun is properly inspected before use, may be more properly classified under accidents than failures. A modern machine gun in the hands of experts should never jam, while failure of automatic fire will be rare and momentary. Until this standard has been reached a machine-gun detachment cannot be considered fit to begin tactical training. The Japanese in the late war were obliged to improvise the detachments for their hastily acquired machine guns; and Captain Matsuda, who commanded the machine guns with Prince Kanin’s Cavalry Brigade, says: “Whereas at the battle of Peu-si-lau on October 12th we had some trouble after firing 1,800 rounds, on March 3rd the guns of one section after firing 11,000 rounds continued to work perfectly. _The gunners were absolutely familiar with their weapons._” Lieut.-General Sir C. J. Burnett, K.C.B.,