At the above command the 2nd and 3rd sections stand fast until the 1st and 4th sections have cleared their front. They then move to their places led by the corporal at the head of their respective sections. This movement will be executed at first in quick time; as men become more proficient, in double time and at a run. IV 1. The arrangement of specialists in the reinforcing platoon differs somewhat from the assaulting platoon. The hand grenadiers of the reinforcing platoon are sent forward in two squads to follow in rear of the 2nd line of the first wave at a distance of about 15 yards. The two squads are abreast of each other, the section sergeant between them. 2. The rifle grenadiers of the reinforcing platoon are then moved up into the 1st line. 3. The riflemen of the reinforcing platoon remain in the 2nd line. 4. The position of the platoon leader of the reinforcing platoon is in front of the center of the 1st line. The position of the 2nd in command is the same as in the assaulting platoon. [Illustration: PROVISIONAL ORGANIZATION OF A PLATOON—RIFLE COMPANY] [Illustration: PROVISIONAL ORGANIZATION OF A PLATOON IN CLOSE ORDER AND FOR ADMINISTRATION] [Illustration: DIAGRAM OF PLATOON IN LINE (CLOSE ORDER) FORMATION FOR ATTACK PLATOON AS FIRST WAVE RIGHT FLANK THE OUTER FLANK] [Illustration] [Illustration] CHAPTER II DEVELOPMENT OF A POSITION FROM AN OPEN WARFARE BATTLE =General Use of Fortifications.= The first use of fortifications, whether hasty or permanent, is to give shelter against hostile fire. The more deliberate use of fortifications is to increase the holding or fighting power of troops by the proper employment of the natural defensive features of the ground and by artificial devices. Successive Phases of the Organization =Change from Battle Lines to Trenches of a Position.= During a battle, as we understand it in open warfare, as soon as the fighting lines are halted for any reason, every man immediately begins to dig in for shelter against the enemy’s fire. If the halting of these fighting lines is more or less permanent these “skirmish holes” are connected, and we have the beginning of a rude trench. We must remember that in a battle troops are disposed in depth in a series of lines. All these lines dig for protection in a similar manner, giving the beginning of several lines of trenches. If the troops remain for any time in this position, it is necessary to have routes from the rear to the front to carry up ammunition and supplies to the different lines. These communication routes are also dug in, and we have the beginning of communicating trenches. Soon the men will begin to seek better protection against rain, cold, and overhead fire, and build themselves some kind of shelters. In a similar manner command posts and supply depots are established.