As I remember it (and my memory is not as good as it used to be), the following
hand signals were used in the German army:
1- Right hand up straight, palm forward, arm stiff and erect: Attention.,
shut up, quiet.
2- Right arm up straight with hand straight, palm forward, then dropping the
arm, still straight forward: Advance.
3- Right arm pumping up and down, with balled fist: Hurry, fast.
4- Right arm straight up, palm straight out to the right, then drop arm to the
side, up again, drop again: Take cover.
5- Right arm bent straight out, lower arm straight up, bent fist, then left
hand hitting upper right arm: The hell with you (analogous to a familiar
signal given with the middle finger right hand).
6- Finger tips of right hand together, then moved to lips, back and forth:
Time to eat.
I am sure there were others. Some of these may have been international,
or may be by now. I would like to hear from others.