66. REFERENCES. For the basic doctrine governing troop movements, see FM 100-5. For technical and logistical data pertaining to troop movements, see FM 101-10. For detailed treatment of motor movements, see FM 25-10. For details of march hygiene, see FM 21-10. For check lists for march orders and march tables, see FM 101-5. For details of marches of artillery battalions and batteries, see FM 6-101.

67. GENERAL. When the command marches in multiple columns each column usually includes some artillery. Artillery is attached to the march group until centralized control is ordered by a higher headquarters. Artillery reconnaissance, survey, and liaison personnel habitually march with forward elements of the command. Marches may be classified according to the imminence of contact, and according to whether the march is made during daylight or at night.

68. DAY MARCHES. During the day, when the column is marching in the presence of the enemy, the disposition of artillery units in the column is determined by tactical considerations, time and space factors, the road net, and condition of the roads.

69. NIGHT MARCHES. Artillery is of little combat value during a night march. Consequently, at night artillery units usually march at the tail of the combat elements of the main body during an advance and at the head of the combat elements during a retrograde movement. If the night march is to extend beyond daybreak, the artillery is located to facilitate its possible action after daybreak.

70. ADVANCE GUARD ARTILLERY.

a. Strength. The strength of the advance guard artillery depends upon the ability of the artillery with the main body to occupy positions to support the advance guard when contact is made and the advance guard is deployed. If the artillery with the main body cannot support the advance guard, some artillery is attached. Usually one battery of light artillery is attached to an advance guard of one basic infantry (cavalry) (armored) battalion. This battery should be reinforced by liaison personnel and equipment and a section from the ammunition train. For larger advance guards, a battalion may be attached. Medium artillery is attached to the advance guard artillery if its early employment is foreseen.

b. Dispositions. The artillery of the advance guard should be located so that it can enter action promptly, and so that other elements of the advance guard can protect it from enemy surprise attacks. The commander of the advance guard artillery marches with the advance guard commander. Reconnaissance and survey personnel of advance guard artillery accompany the leading elements of the column. When the advance guard deploys, its artillery occupies position to cover the deployment.

71. REAR GUARD ARTILLERY.

a. Strength. The rear guard should be especially strong in artillery. Less than a battalion is seldom attached to the rear guard of a division; medium artillery should be included.

b. Dispositions. Rear guard artillery usually marches by bounds in the interval between the main body and the rear guard. The commander of the rear guard artillery marches with the commander of the rear guard. When the rear guard is deployed, the rear guard artillery occupies positions to permit early delivery of fire on hostile columns.

72. FLANK GUARD ARTILLERY. The employment of artillery with a flank guard is similar to the employment of advance guard artillery. When no artillery is attached, the artillery of the main body is so disposed as to facilitate prompt support of the flank guard.

73. REFERENCES. For general procedures governing movements by rail and water, see FM 100-5. For technical and logistical data pertaining to rail and water movements, see FM 101-10. For check list for orders and for entraining and detraining tables, see FM 101-5. For the general organization, operation, and control of rail and water transportation, see FM 100-10. For details of artillery movements by rail and water, see FM 6-101 and AR 55-145.

74. ARTILLERY DURING MARCH HALTS. When the command makes a long halt during a march in the presence of the enemy, the advance, flank, and rear guards establish march outposts. Units of the support occupy critical terrain features, establish outguards, and send out patrols. Antiaircraft and antimechanized defense are stressed.

75. ARTILLERY IN BIVOUAC. When the command bivouacs in the presence of the enemy, an outpost is organized (FM 100-5). The column commander assigns bivouac areas to artillery units in his column. Artillery positions are selected primarily to permit support of the outpost line of resistance. Positions are prepared for all-round defense. Installations are dispersed. The positions should permit fire on the probable routes of approach and on critical areas that cannot be covered by infantry weapons. The artillery attached to the outpost usually occupies position. The commander of the artillery establishes his command post near that of the outpost commander. Defensive fires are prearranged; liaison, observation, and communication are established.