USING THE FLAG 193 



To signal with the Morse code four arms and the indicator are required. An 

 arm placed at an angle of 45 to the upright post forms a dot of the code; one placed 

 horizontally or at an angle of 90 forms a dash. The signals are read from the top 

 down. The front or "3" of the Myer or Wigwag code is made by dropping all arms 

 to the vertical position. Although limited in range and, except in the smaller sizes, 

 slow to operate, this apparatus may sometimes be found useful on lookout stations', 

 especially those equipped with towers and read from only one direction. The con- 



ANNULLING 



NTERRQGAT 



.TTENTlON 



O 



SIGNALS 

 (FOLLOW) 



NEGATIVE PREPARATOR 



ACKNOWLEDGE 



LETTERS 



NTERVAL 



Pig. 112 Two-arm, fixed semaphore code 



struction is simple and the signals more easily read than the flag at a similar dis- 

 tance. Code messages are readily set on a fixed semaphore and kept displayed for 

 long periods. In fact, this is by far the most useful application of the fixed sema- 

 phore to forest protection, and, as about 650 code messages can be sent using one 

 and two letters only, by building a semaphore with two sets of movable arms on a 

 lookout peak any one of the 650. messages may be set on the semaphore and left dis- 

 played to the view of the entire protection staff within range of the station. The 

 arms should be painted according to the colour of the background against which 

 they are displayed. Yellow or orange with a red strip will generally be found mrst 

 effective. 



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