Troops are set in motion by words of command, and, when these do not suffice, by orders. (Orders give information of the situation and the intentions of the commander, and assign tasks, but leave the recipient free to choose the method of carrying them out). When commands are given from a distance, time and energy may be saved by employing the telephone and visual signals. To these may be added shouts, signs, and the following signals: _To advance_, the leader raises the arm; to indicate that the command is _to follow him_, he extends his raised arm in the direction of march; _to halt_, he lowers the arm; _to deploy_, both arms are raised laterally to the height of the shoulders, and if necessary the direction the skirmish line is to take is subsequently indicated with one extended arm; _to assemble_ his men, the leader describes a circle above his head with one arm. These signals may also be made with the sabre or rifle. Additional signals should be agreed upon beforehand in each separate case. If a signal is made to a body of troops in close order, it is meant, in the first place, for its leader. (Par. 11 German I. D. R.). Other signals, such as those indicating a change of direction of march, or a change in the battle formation, must be specially agreed upon beforehand. Trumpet signals are only used by troops in garrison at drills, and in barracks or billets as service calls. To prevent troops from misunderstanding signals or from obeying those not intended for them, all trumpet calls in battle, except “charge,” “fix bayonet,” and “attention,” are forbidden. During the engagement of =Trautenau= (27th June, 1866), the trumpet signal “assemble,” given at another point, caused four Prussian battalions to withdraw.[55] See also the effect of the signal “assemble” after the taking of =Problus=.[56] Notice the effect of the signal “form square” during the assault on the =Forest of Bor= (=Königgrätz=).[57] [55] KÜHNE, _Kritische Wanderungen_, 3, 2nd Edition, pp. 55 and 85. [56] _Geschichte des Infanterie-Regiments Nr. 16_, p. 230. [57] _Geschichte des Infanterie-Regiments Nr. 57_, p. 47. HÖNIG, _Untersuchungen über die Taktik der Zukunft_, 4th Edition, p. 61. On the morning of June 26th, 1866 (day of rest), reveille sounded by a trumpeter was mistaken for an alarm signal. The 7th Infantry Division assembled and the signal was repeated in two other army corps. Two days previous another useless alarm had occurred because a trumpeter, surprised by a number of Radetzky Hussars, had blown the alarm signal.[58] [58] _Geschichte des Regiments Nr. 66_, pp. 48/49.