[582.] In action, the formation and location of the support must be such as to gain and give timely information of the enemy's approach and to offer actual resistance to the enemy beyond effective rifle range of the artillery's flanks. It should not be close enough to the artillery to suffer from fire directed at the artillery. In most cases a position somewhat to the flank and rear best fulfills these conditions.
[583.] The support commander is charged only with the protection of the artillery. The tactical employment of each arm rests with its commander. The two should cooperate.
INTRENCHMENTS.
([Plate V.])
[584.] Ordinarily, infantry intrenches itself whenever it is compelled to halt for a considerable time in the presence of the enemy.
Infantry charged with a resisting mission should intrench whenever there is any likelihood that the cover constructed will be of use.
[585.] Except in permanent fortifications or in fortifications prepared long in advance, the infantry plans and constructs the field works that it will occupy.
When performing their duties in this connection officers should bear in mind that profile and construction are simple matters compared with location and correct tactical use.
[586.] Intrenchments enable the commander to hold a position with the least possible number of men and to prolong his line or increase his reserve.
They are constructed with a view to giving cover which will diminish losses, but they must not be so built or placed as to interfere with the free use of the rifle. Fire effect is the first consideration.