Freehand firing increases the rate of fire. Whether the skirmisher fires freehand or from a rest is of influence on the accuracy of the single shot at short ranges. The Belgian, Dutch, and Italian regulations authorize the bayonet, in the absence of other expedients, to be stuck into the ground as a rifle-rest, while this is forbidden in Germany. Collective fire of short duration delivered at mid ranges has not been found superior because of the use of rifle-rests. Fire delivered from a rest is undoubtedly superior, however, when the barrel of the piece is heated by continued firing (position of the left hand supporting the piece when firing standing, prone, or kneeling) and when the arm of the skirmisher gets tired. When firing from a rest, high shots result from vibrations of the barrel;[166] and there is also danger, when under fire, that the men will not raise their heads over the parapet, but will fire their pieces into the air. This, as corroborated by the more recent campaigns, is why a fire fight at short range is by no means decided in so short a time as the peace performances of modern rifles lead one to suppose, for great losses do not take place until skirmishers, who have heretofore hugged the ground, rise. At Spionskop, the two opposing firing lines remained stationary for hours at 250 m. from each other.[167] The Japanese found in their attacks that at ranges from 150 to 75 paces the hostile fire had no effect. [166] According to the _Swiss Firing Regulations_ the change in height in the point of the target struck amounts to ¹⁄₁₀₀₀ of the range. [167] The British Infantry (consisting of 2694 men, exclusive of subsequent reinforcements), which was engaged at short range on Spionskop from 3 A. M. until 9:30 P. M., lost 40 officers and 721 men in 18¹⁄₂ hours (one officer to every 18.5 men), _i.e._, 28.2%. See p. 189 infra. (f) Influence of the Ground.[168] [168] MONDEIL, _De la résolution des problèmes de tir sur le champ de bataille_, Paris, 1900. 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.[169] [169] 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.