60 to 90 seconds is sufficient time to obtain the desired effect, and before the enemy’s artillery can get the range a second signal from the commander sends the guns out of action again as rapidly as they appeared. This is one of the most successful methods of employing machine guns: there is no risk of being seen before the target appears, there is no “giving away the position” by careless scouts, and there is no chance that a powerful pair of glasses will discover the guns in position before they open fire and turn the tables by surprising them instead. On the other hand, it requires very highly trained detachments and a vast amount of peace practice to ensure its success in war. Alternative positions are always necessary when the deliberate method is used, and must be carefully practised in peace--the principal points to be observed being: (1) That the second position is suitable for bringing effective fire to bear on the enemy, and (2) that the gun is able to gain the position without exposure. Scouts so often forget that they can work with ease where it is impossible to carry a gun; and unless the above conditions are fulfilled, the alternative position will be useless. The place for dismounting the guns must always be as close to the fire position as possible without exposing the teams to fire or view; the reserve ammunition must be brought up to this spot, and precautions must be taken to prevent the teams being surprised from the flanks or rear if exposed. Machine guns should never be advanced for a short distance. If it is desired to obtain a closer range, nothing is gained by moving two or three hundred yards, while the guns are exposed to considerable risk. The guns are just as effective at 1,000 yards as at 800, and when a closer range is necessary they must await the opportunity for moving up to close range, _i.e._, 300 or 400 yards, where their fire may be decisive. COVER Cover may be of two kinds: (1) _Cover from fire._ (2) _Cover from view._ Cover from fire must be proof against the projectiles likely to be used against it--that is, against rifle fire and shrapnel. “Cover from fire” should also be “cover from view” if possible; it must be inconspicuous, and should be of the same colour and material as the background and locality. It must be as low as is compatible with command, and must never be on the skyline. The following points in the order given constitute good “cover from fire”: (1) Bullet proof. (2) Good field of fire. (3) Invisibility. (4) Protection from enfilade fire. (5) Good line of retreat (under cover). “Cover from view” is often not cover from fire, and must be used with great caution; it is the principal means by which guns are brought up to the fire position without the enemy’s knowledge, thus effecting a surprise. Cover may be either (1) natural, (2) artificial, (3) a combination of both.