=451. Density of whole deployment varies with size of command.= The density of the whole deployment increases with the size of the command, because the larger the command the greater the necessity for reserves. Thus, battalion acting alone may attack two men per yard of front, but a regiment, with three battalions, may only double the front of the one battalion. (437)

=452. Division of battle line into battle districts and density of deployment therein.= By the a.s.signment of divisions or larger units to parts of a line of battle several miles long, a series of semi-independent battle, or local combat, districts are created.

The general deployment for a long line of battle comprising several battle districts is not directly considered in these regulations. The deployments treated of herein are those of the infantry within such districts.

The density of deployment in these districts may vary greatly, depending upon the activity expected in each. Within these battle districts, as well as in smaller forces acting alone, parts of the line temporarily of less importance may be held weakly, in order to economize troops and to have more at the decisive point. (438)

=453. Extent of front occupied by a unit depends upon security of flanks.= The front that a unit may occupy when deployed depends also upon whether its flanks are secured. If both flanks are secured by other troops, the unit may increase its front materially by reducing its reserve or supports. If only one flank is so secured, the front may still be somewhat increased, but the exposed flank must be guarded by posting the supports or reserve toward that flank.

Natural obstacles that secure the flanks have practically the same effect upon deployment. (439)

=454. Regiments, battalions, and companies deployed side by side.= Except when a.s.signed as supports or reserve, regiments in the brigade, battalions in the regiment, and companies in the battalion are, when practicable, deployed side by side. (440)

=455. Battalions furnish firing line and supports; larger units furnish reserves; employment of reserve.= In the deployment, battalions establish the firing line, each furnishing its own support.

In each unit larger than the battalion a reserve is held out, its strength depending upon circ.u.mstances. In general, the reserve is employed by the commander to meet or improve conditions brought about by the action of the firing line. It must not be too weak or too split up. It must be posted where the commander believes it will be needed for decisive action, or where he desires to bring about such action.

When necessary, parts of it reenforce or prolong the firing line.

(441)

ATTACK

(For the battalion in Attack, see pars. 342-346)

=456. Fire superiority means success; how to obtain fire superiority.= An attack is bound to succeed if fire superiority is gained and properly used.

To gain this superiority generally requires that the attack employ more rifles than the defense; this in turn means a longer line, as both sides will probably hold a strong firing line. (442)

=457. When frontal attack may be successful.= With large forces, a direct frontal attack gives the attacker little opportunity to bring more rifles to bear. However, if the enemy is unduly extended, a frontal attack may give very decisive results. (443)

=458. When turning movements are allowable.= Owing to the difficulty of control and the danger of the parts being defeated in detail, wide turning movements are seldom allowable except in large forces. (444)

=459. Advantages of enveloping attack.= If the attack can be so directed that, while the front is covered, another fraction of the command strikes a flank more or less obliquely (an enveloping attack), the advantages gained are a longer line and more rifles in action; also a converging fire opposed to the enemy's diverging fire. (445)

=460. Envelopment of both flanks.= An envelopment of both flanks should never be attempted without a very decided superiority in numbers. (446)

=461. Enveloping attacks result in local frontal attacks; advantage of envelopment.= The enveloping attack will nearly always result locally in a frontal attack, for it will be met by the enemy's reserve. The advantage of envelopment lies in the longer concentric line, with its preponderance of rifles and its converging fire. (447)

=462. Cooperation between frontal and enveloping attacks; the two attacks to be deployed considerable distance from hostile positions.= Cooperation between the frontal and enveloping attacks is essential to success. Both should be pushed vigorously and simultaneously, and ordinarily both should move simultaneously to the charge; but at the final stage of the attack conditions may sometimes warrant one in charging while the other supports it with fire.

The envelopment of a flank is brought about with difficulty when made by troops already deployed in another direction or by their reserves.

The two attacks should be deployed at a suitable distance apart, with the lines of attack converging in rear of the hostile position. The troops that are to make the enveloping attack should deploy in the proper direction at the start and should be given orders which enable them to gain their point of deployment in the most direct and practical manner.

The enveloping attack is generally made the stronger, especially in small forces. (448)

DEPLOYMENT FOR ATTACK

=463. Distance from hostile position at which deployment is made; foreground to be cleared of hostile detachments before deployment.= Where open terrain exposes troops to hostile artillery fire it may be necessary to make the deployment 2 miles or more from the hostile position.

The foreground should be temporarily occupied by covering troops. If the enemy occupies the foreground with detachments, the covering troops must drive them back. (449)

=464. Moving well forward and deploying at night.= To enable large forces to gain ground toward the enemy, it may sometimes be cheaper and quicker in the end to move well forward and to deploy at night. In such case the area in which the deployment is to be made should, if practicable, be occupied by covering troops before dark.

The deployment will be made with great difficulty unless the ground has been studied by daylight. The deployment gains little unless it establishes the firing line well within effective range of the enemy's main position. (See Night Operations, par. 580-590.) (450)

=465. Each unit deploys on its direction line; intervals between battalions on firing line.= Each unit a.s.signed a task deploys when on its direction line, or opposite its objective, and when it has no longer sufficient cover for advancing in close order. In the firing line, intervals of 25 to 50 yards should be maintained as long as possible between battalions. In the larger units it may be necessary to indicate on the map the direction or objective, but to battalion commanders it should be pointed out on the ground. (451)

=466. Post of reserve; reserve charged with flank protection.= The reserve is kept near enough to the firing line to be on hand at the decisive stage. It is posted with reference to the attack, or to that part of the attacking line, from which the greater results are expected; it is also charged with flank protection, but should be kept intact.

Supports are considered in paragraphs 262 to 265, inclusive, and 335 to 339, inclusive. (452)

ADVANCING THE ATTACK

=467. Firing line to advance as far as possible before opening fire.= The firing line must ordinarily advance a long distance before it is justified in opening fire. It can not combat the enemy's artillery, and it is at a disadvantage if it combats the defender's long-range rifle fire. Hence it ignores both and, by taking full advantage of cover and of the discipline of the troops, advances to a first firing position at the shortest range possible, as explained in par. 344.

Formations for crossing this zone with the minimum loss are considered in paragraphs 249 to 257, inclusive. These and other methods of crossing such zones should be studied and practiced. (453)

=468. Invisibility best protection while advancing.= The best protection against loss while advancing is to escape the enemy's view.

(454)

=469. Advance of battalions.= Each battalion finds its own firing position, conforming to the general advance as long as practicable and taking advantage of the more advanced position of an adjacent battalion in order to gain ground.

The position from which the attack opens fire is further considered in paragraphs 343-345, inclusive. (455)

=470. Infantry moving to the attack pa.s.sing through deployed artillery.= It will frequently become necessary for infantry moving to the attack to pa.s.s through deployed artillery. This should be done so as to interfere as little as possible with the latter's fire, and never so as to cause that fire to cease entirely. As far as practicable, advantage should be taken of intervals in the line, if any. An understanding between artillery and infantry commanders should be had, so as to effect the movement to the best advantage. (456)

=471. Advanced elements of firing line not to open fire on main hostile position.= In advancing the attack, advanced elements of the firing line or detachments in front of it should not open fire except in defense or to clear the foreground of the enemy. Fire on the hostile main position should not be opened until all or nearly all of the firing line can join in the fire. (457)

THE FIRE ATTACK

(See pars. 414-438.)

=472. Fire superiority sought at first firing position, and to be maintained until charging point is reached; size of rushing units.= At the first firing position the attack seeks to gain fire superiority.

This may necessitate a steady, accurate fire a long time. The object is to subdue the enemy's fire and keep it subdued so that the attacking troops may advance from this point to a favorable place near the enemy from which the charge may be made. Hence, in the advance by rushes, sufficient rifles must be kept constantly in action to keep down the enemy's fire; this determines the size of the fraction rushing. (458)

=473. Futility of advancing without fire superiority.= To advance without fire superiority against a determined defense would result in such losses as to bring the attack to a standstill or to make the apparent success barren of results. (459)

=474. Signs that fire superiority has been gained.= Diminution of the enemy's fire and a p.r.o.nounced loss in effectiveness are the surest signs that fire superiority has been gained and that a part of the firing line can advance. (460)

=475. Retiring under fire in daylight suicidal; intrenching.= The men must be impressed with the fact that, having made a considerable advance under fire and having been checked, it is suicidal to turn back in daylight.

If they can advance no farther, they must intrench and hold on until the fall of darkness or a favorable turn in the situation develops.

Intrenching is resorted to only when necessary. Troops who have intrenched themselves under fire are moved forward again with difficulty. (461)