The methods of carrying out indirect covering fire will vary according to the nature of the position selected and the way the guns are to be laid. This is one of the few occasions when a battery or two may have all their guns in line close together. If the slope is a steep one, they may be pushed up close to the crest, but on a gentle slope they must be placed sufficiently far back to avoid the forward effect of shrapnel bursting on the crest line.
The battery commander will select the position for the guns and will then give each gun or section a section of front to fire on. The method of marking off this section is as follows: two iron rods about 3 ft. long for each gun are painted white, and are then "laid off" from the gun to the target, in an exact line, the first being on the reverse slope a few yards short of the crest; the next on or just behind the crest line. By aligning the gun on the rods, fire is brought on the centre of the target; should traversing fire be required, the limits may be marked by similar sticks on either side.
There are two methods of laying the gun. (1) By observation of fire. (2) By quadrant elevation. The first method has been already described, and the second must be done by using the following table in conjunction with an instrument for elevating the gun at the required angle; but it must be remembered that each gun will require adjusting to its own angle of elevation to suit its known error at each range.
