Japanese found in their attacks that at ranges from 150 to 75 paces the hostile fire had no effect.
(f) Influence of the Ground.[1]
So far we have considered only the effect of infantry fire on level ground. The efficacy of fire is, however, greatly influenced by the inclination of the ground upon which the cone of dispersion falls. Where the ground rises in respect to the line of sight, the depth of the beaten zone is decreased; where it falls in respect to the line of sight, the depth of the beaten zone is increased.[2]
The importance of this circumstance is frequently so magnified in the
French infantry that sight is lost of tactical requirements. For example,
they employ formulae to ascertain the point from which a height can be
covered with grazing fire, or propose to defend the ascent to a plateau by
evacuating the military crest and occupying the reverse slope, keeping the
slope facing the enemy under a grazing fire with the tail ends of the
trajectories.
- ↑ Mondeil, De la résolution des problèmes de tir sur le champ de bataille, Paris, 1900.
- ↑ Lieutenant-General Rohne's definitions are given below in explanation of certain technical terms: "Danger Space" is the distance measured along the line of sight within which the trajectory neither rises above the height of the target nor falls below the target. "Beaten Zone" is the distance measured along the surface of the ground within which the trajectory does not rise above the height of the target. Whether a target will be struck by a bullet when the range has not been correctly estimated depends entirely upon the danger space. In pointing at the bottom line of the target, the aiming position (i.e., the height at which the piece is held) does not affect the danger space. When pointing at the center of the target the danger space changes, increasing for low rear sight elevations and tall targets, and decreasing for high rear sight elevations and low targets, as compared with aim taken at the bottom line of a target. "The evil effects of errors in estimating the range decrease as the 'danger space' increases, which, by the way, is wholly dependent upon the ballistic properties of the rifle, upon the range, and the height of the target. The danger on the ground in rear of the target fired upon, and the difficulty of bringing up reinforcements and ammunition over it, increases directly as the beaten zone, which in addition depends upon the inclination of the ground to the line of sight."
