Whether machine guns are distributed by platoons, or are employed as a unit under control of superior leaders, will depend upon whether it is contemplated to employ them in a purely defensive way for the purpose of reinforcing the several weak points, or offensively in fire surprises or in covering the flanks. The distribution by platoons has the undeniable disadvantage that single guns will frequently not find an opportunity to fire; that the difficulty of ammunition supply is increased; and that the combined employment of the several platoons will produce friction that cannot be easily avoided. On the other hand, in machine gun batteries of three platoons each, an employment by platoons is easy. Although a distribution by platoons is permissible in a passive defense, the employment of the guns by battery (company) against the flanks of the attacker permits the mobility and fire power of the arm to be utilized to better advantage. While a distribution of machine guns by platoons--if we except colonial and mountain warfare--is, indeed, cheaper, it generally leads to a useless frittering away of fighting units.[299] [299] Lieutenant ULRICH (retired), who participated in the fighting in Manchuria, voices the same opinion in _Jahrbücher_, March number, p. 285: “The opinion has been quite prevalent that the organization of strong machine gun units is one of the most important requirements of modern battle.” Machine guns will be able to bring all their powers into play to the best advantage at the beginning of a rencontre, when, from their position as far forward as possible in the column, they are pushed to the front to occupy important points and to compel the enemy to deploy his infantry. The commander should, however, endeavor to withdraw the machine guns from the fight as soon as his own infantry has deployed, in order to avoid involving the guns in a protracted fire fight necessitating an expenditure of a great amount of ammunition and in which the accuracy of their fire would gradually suffer.[300] The proper sphere of machine guns lies in their employment as a separate arm, whether they are posted so as to flank an enemy, or are kept at the disposal of the commander as an ever ready reserve, which is pushed forward to keep the point to be attacked under fire, to meet a counter-attack, or--and to this use they are best adapted--to participate in the pursuit. Their employment is also proper in rear guard actions, since they are able to remain in position longer, for example, than rear guard infantry, whose energies are paralyzed by the thought of getting away from the enemy in time. Machine guns are much more independent than infantry on account of their ability to withdraw at an increased gait. On account of their greater staying power and the greater intensity of their fire, they increase the delay which the enemy suffers, as well as the start gained by their own force;