The commanding officer who at present looks upon his machine guns in much the same light as he regards any other portion of his first-line transport--a necessary encumbrance taking away an officer and several men from their proper duties, and a source of anxiety when the regiment goes into action--would regard them with very different feelings if assured of their efficiency and relieved of the responsibility for their tactics and safety. That this is possible without altering the present organisation has been shown; that it is absolutely essential for their efficient use in war it is hoped to demonstrate in the chapters that follow. CHAPTER II GENERAL PRINCIPLES “Each arm has its special characteristics and functions, and is dependent on the assistance of others; the full power of an army can be exerted only when all its parts act in close combination, and this is not possible unless the members of each arm understand the characteristics of the other arms.” The above paragraph from _Field Service Regulations_, Part I., 1909, aptly illustrates a principle which should be impressed upon every serious machine-gun student, for the principles of machine-gun tactics are based upon those of the arm with which they are co-operating. The machine gun cannot yet be regarded as a separate “arm” in our service, nevertheless it possesses a power peculiar to itself; and until this power is studied and thoroughly understood, the principles that should govern its employment in the field cannot be grasped, and consequently its effective use is dependent on chance or accident, and for every success scored a dozen failures will occur, any one of which may be fatal. The preceding chapter has dealt with the peculiarities and power of the machine gun, and it will be seen that it possesses the fire effect of the infantry arm while it has several of the characteristics peculiar to artillery; for instance, it is fired from a mounting by one man, and is moved from position to position by draught or pack animals. We have seen that the chief characteristic of the machine gun is its power of delivering the “maximum fire from the minimum front”; this fire is of great volume and is highly concentrated, while it can also be made to sweep a wide lateral surface of ground. The gun’s narrow frontage in action renders it easy to conceal, and when discovered it presents a very small and difficult target to the enemy’s riflemen; on the other hand, when once discovered if it cannot be moved unseen to another position it is liable to suffer a prolonged and concentrated fire from the widely scattered riflemen of the enemy, to which it cannot effectively reply, and which must in time cause loss. Again, its range being limited, it is powerless against artillery except under special circumstances at effective rifle range. The general principles governing its tactical employment depend upon three factors, viz. (1) the target, (2) the range, (3) the position.