The heavy field artillery in our service comprises 4.7” and 5” rifles and 6” and 7” howitzers. Their range is much greater than that of the pieces of the light field artillery. In a general way we may say that these heavy pieces will be used only against hostile batteries, earth works and material objects or against troops caught in some mass formation. They will generally not be used against an advancing skirmish line or troops in proper formation to meet light artillery fire. There is no training to be given infantry except discipline to hold them to their duty in an earth work under fire by heavy field artillery, hence in this chapter we may ignore it. [Sidenote: Light artillery] With light field artillery it is very different. The light field artillery is what concerns us most in our training. The extreme range for which these guns are sighted is 6500 yards, and at all ranges under 5000 yards they can produce serious losses on infantry exposed to their fire. They use two classes of projectiles, shell and shrapnel. The high explosive shell has a much smaller radius of action than the shrapnel, but is very effective within this area. It is generally used to batter material objects and with high angle fire to get at men in trenches or behind cover. [Sidenote: Shrapnel] The shrapnel of the 3” rifle contains 252 bullets and on burst these bullets are scattered over an area, roughly speaking, elliptical in form, 200 yards in depth by 25 yards in width. The flatter the trajectory, the deeper becomes the pattern made; the width practically does not vary. In other words the 252 bullets are scattered on burst over an area of 5000 square yards. If these bullets were uniformly distributed there would be _one_ for every 20 square yards or an area of 15 x 12 feet. They are, however, not evenly distributed, being thicker in a small area near the front end. This bullet will not penetrate the infantry soldier’s pack at any range, so that when lying on the ground his pack affords complete protection to his spine and considerable protection to all vital parts except his head. The chance then of a man being wounded by a single shrapnel, even when inside the cone of dispersion, would only be about 1 in 80 if in the open and very much less with partial cover, as a trench, log, etc. The shrapnel bullet will not pass through one man and wound a second as will the infantry bullet. [Sidenote: Rate of fire] While artillery can fire very rapidly once the range data is accurately determined it requires considerable time to get into position and determine this data. Until then it is harmless. [Sidenote: Moving target] An erratically shifting target is hard for artillery to keep on. The fuze must be so set that the burst is at the proper height and distance to the front of the target to be effective, both not easy especially in case of a moving target, and the more erratic the movement the harder is the task of the artillery-man. [Sidenote: On the defensive]