=66. Turn on fixed and moving pivots.= The turn on the fixed pivot by subdivisions is used in all formations from line into column and the reverse. The turn on the =moving pivot= is used by subdivisions of a column in executing changes of direction. (17) =67. Partial changes of direction.= Partial changes of direction may be executed: By interpolating in the preparatory command the word =half, as Column half right (left), or Right (left) half turn=. A change of direction of 45 deg. is executed. By the command: =INCLINE TO THE RIGHT (LEFT).= The guide, or guiding element, moves in the indicated direction and the remainder of the command conforms. This movement effects slight changes of direction. (18) =68. Line of platoons, companies, etc.= The =designations line of platoons, line of companies, line of battalions=, etc., refer to the formations in which the platoons, companies, battalions, etc., each in column of squads, are in line. (19) =69. Full distance in column of subdivisions; guide of leading subdivision charged with step and direction.= Full distance in column of subdivisions is such that in forming line to the right or left the subdivisions will have their proper intervals. In column of subdivisions the guide of the leading subdivision is charged with the step and direction; the guides in rear preserve the trace, step, and distance. (20) =70. Double rank, habitual close order formation; uniformity of interval between files obtained by placing hand on hip.= In close order, all details, detachments, and other bodies of troops are habitually formed in double rank. To insure uniformity of interval between files when falling in, and in alignments, each man places the palm of the left hand upon the hip, fingers pointing downward. In the first case, the hand is dropped by the side when the next man on the left has his interval; in the second case, at the command front. (21) =71. Posts of officers, noncommissioned officers, and special units; duties of file closers.= The posts of officers, noncommissioned officers, special units (such as band or machine-gun company), etc., in the various formations of the company, battalion, or regiment, are shown in plates. In all changes from one formation to another involving a change of post on the part of any of these, posts are promptly taken by the most convenient route as soon as practicable after the command of execution for the movement; officers and noncommissioned officers who have prescribed duties in connection with the movement ordered, take their new posts when such duties are completed. As instructors, officers and noncommissioned officers go wherever their presence is necessary. As file closers it is their duty to rectify mistakes and insure steadiness and promptness in the ranks. (22) =72. Special units have no fixed posts except at ceremonies.=