In Switzerland and England,[134] it is recommended that supports use “Fire of position” where the terrain is suitable (hilly country). The German Infantry Drill Regulations (par. 340) contain a similar provision. When the supports cannot see the firing line on account of the conformation of the ground, this fire is not likely to endanger the latter. [134] _Infantry Training_, 1905, p. 132, par. 2; p. 134, pars. 1, 2; p. 136, par. 6; p. 155, par. 1. See p. 154, infra. 5. ASCERTAINING RANGES. (Pars. 78-98, 190 and 191 German I. F. R.). Efficacy of fire depends upon a knowledge of the range. An imperfect knowledge of the range may be compensated for by the flatness of the trajectory of the individual rifle and by the favorable conformation of the ground in respect to the cone of dispersion. In collective fire, at mid and long ranges, each rear sight graduation commands a beaten zone approximately 100 m. deep--good aim, proper elevation, and careful firing being presupposed. The nearer the target is to the densest portion of the cone of dispersion, the greater the efficacy of the fire. The following results were obtained in Italian firing tests in which 100 skirmishers fired at a plate 1 m. high and 30 m. wide with the 6.5 mm. rifle: =====================+======================+======================= | MEASURED RANGE. | ESTIMATED RANGE. +----------+-----------+----------+------------ | Slow fire| Rapid fire| Slow fire|Rapid fire | [135] | [135] | [135] | [135] |Percentage|Percentage |Percentage|Percentage | of hits. | of hits. | of hits. | of hits. ---------------------+----------+-----------+----------+------------ At 500 m. | 21.5 | 15.8 | 14.8 | 11.3 At 1000 m. | 11.1 | 8.1 | 6.5 | 5.3 At 1500 m. | 5. | 3.4 | 2.6 | 2.2 Average results at-- | | | | Ranges under 1000 m. | 18.2 | 13.6 | 12.1 | 9.3 Ranges over 1000 m. | 7.1 | 5.1 | 3.2 | 3.2 ---------------------+----------+-----------+----------+------------ [135] Slow fire four shots, rapid fire fourteen shots, per minute. Beyond 600 m., an error in the range exerts a greater influence upon the efficacy of fire than does the marksmanship of the skirmishers.[136] When an improper elevation has been selected, the efficacy of the fire decreases as the compactness of the “cone of dispersion” increases; in other words, the efficacy of the fire decreases as the excellence of the marksmanship of the men and their coolness in the face of the enemy increase. (See pp. 170 and 171, infra). [136] ROHNE, _Das Gefechtsmäszige Abteilungsschieszen der Infanterie_, p. 13. The following expedients for ascertaining ranges may be mentioned: (_a_) Pacing and galloping;