once it is in action, the second man merely assisting him with the ammunition, etc., but he is not absolutely necessary to the firing of the gun. Thus we see that the killing of the gunner only causes a momentary cessation of fire until another man takes his place, when the fire is resumed without loss of intensity, accuracy, or concentration. We are now in a position to form an accurate estimate of the potentialities of the machine gun and its true tactical value as compared with infantry, and we find: 1. Its fire effect 50 rifles at least. 2. Its mobility Cavalry. 3. Its visibility A file (2 men). 4. Its vulnerability Unaffected by 50% of loss. Before discussing their place in battle and tactical use it will be necessary to say a few words on the best methods of grouping the guns and organising their detachments and the training of the personnel in peace for the duties they will have to perform in war. In our service two machine guns are issued to each regiment of cavalry and battalion of infantry, and the detachment consists of: Cavalry. Infantry. Subaltern 1 1 Sergeant 1 1 Corporal 1 1 Privates 12 12 Drivers 8 2 Bâtmen 2 - -- -- 25 (1 officer) 17 (1 officer) This section of two guns is therefore the smallest tactical unit, and the officer in command is solely responsible for the training and efficiency of his section. It is therefore absolutely essential that the machine-gun section commander should be a subaltern of not less than three years’ service, specially selected for his keenness, efficiency, and self-reliance, who has passed the examination “C” for promotion, and who holds the special machine-gun certificate from a School of Musketry. A “destroyer” in the Royal Navy is commanded by a very junior officer, but he is most carefully selected for similar qualities to those mentioned, and is in addition required to possess the necessary professional qualifications--consequently it is a command much sought after, and competition enables the authorities to appoint the pick of the service and thus obtain the maximum efficiency where efficiency is the essence of successful employment in war. The best and nothing but the best is necessary to the successful employment of machine guns, and the importance of obtaining the very best officers as section commanders is so great that there is reason to doubt the utility of having machine guns at all if they are not commanded and handled by those who are in every way expert in their use.