iii. If the line of fire cannot be marked by planting two aiming posts

(_See_ para. 1) the procedure will be as follows, or as in method iv. below. From his observing station the battery commander, using his director as in ii., sends down the angle to one gun or to the battery director. In the latter case the battery leader or officer who is working the director obtains the line of fire by setting it to the angle ordered. He then measures the angle to an aiming point as described in i. and gives it out to the battery. When the angle is sent to one gun the section commander to whom the gun belongs directs his gun on to the line of fire and the subsequent procedure is as in para. 4 below. In both cases the battery commander will make the necessary correction for displacement before sending down the angle. (_See_ Sec. =123= (3).)