Manual of Military Training Second, Revised Edition
Chapter 4
The Two-Arm Semaphore Code--Signaling with Heliograph, Flash Lanterns, and Searchlight--Sound Signals--Morse Code.
Manual of Military Training Second, Revised Edition
The Two-Arm Semaphore Code--Signaling with Heliograph, Flash Lanterns, and Searchlight--Sound Signals--Morse Code.