German Squad Leader Whistle found at Stalingrad

In the din of battle, signals could be heard much easier from a whistle than by voice.  Two blasts from a whistle for a combat engineer squad might signal to get up and quickly move forward ten meters.  Today, many militaries think of command and control as sophisticated computers, but for the infantryman on the ground, life and death can be determined by understanding quickly what your squad leader wants you to do.