UNITED STATES NAVAL CODE FOR VISUAL SIGNALLING.
To signal with flag or torch "wigwag":
There are but one position and three motions.
The position is with the flag held vertically in front of the body; the signalman facing squarely the point to which the message is to be sent.
The first or 1 is a motion to the right of the sender.
The second or 2 is a motion to the left of the sender.
The third or 3: the flag is dropped in front of the sender and instantly returned to position.
The entire code is made up of these three motions—1, 2, and 3. Every letter begins and ends with position.