CHAPTER XXIII 



USING THE FLAG 



Section 122 General Remarks 



Flag signals are made by either the semaphore or the wigwag system. The former 

 is the more rapid but the latter has by far the greater range, and is the method best 

 adapted to forest-protection uses. Several methods of wigwagging are employed but 

 all agree in having at least two distinct movements of the flag, one representing a dot 

 and the other a dash of the Morse code. A third motion is ^employed in certain con- 

 ventional signals as is the long flash or " 3 " of the IMyer code with the heliograph. 

 The wigwag system which employes motions both to right and left is best adapted to 

 the larger flags and therefore to the longer ranges, and should be employed for forest 

 work, although other more rapid methods for short-range work can be easily acquired 

 subsequently. 



Section 123 Selecting a Station 



The general principles stated in iSection 106 for the selection of heliograph stations 

 also apply to flag stations. With the latter, greater care must be exercised in determin- 

 ing the colour of the background, since this has a- very great influence on the range at 

 which signals may be read. 



To determine the colour of the background, first ascertain whether the com- 

 municating station is higher or lower than, or on a level with, your own. If it be 

 higher, the background for your signals, viewed thence, will be the colour of the field, 

 woods, etc. behind, and lower than, your flagman. If it be lower, your background will 

 be the colour of the ground, etc. behind, and higher than, your flagman. If the sta- 

 tions are of equal elevation, then the background for your signals will be that directly 

 behind the flagman. 



The colour of the flag must contrast as strongly as possible with that of the back- 

 ground. With green or drab, or with earth-covered background, the white flag should 

 be used. The distant station is the best judge of background, and should it indicate 

 the colour of flag wanted, that flag should be used. 



The following table shows the extent of horizon for different heights above sea- 

 level; that J8, it shows how far an object at the sea-level can be seen. 



DISTANCES AT WHICH AN OBJECT AT SEA-LEVEL CAN BE SEEN 



According to the above fig?ires, an observer whose eye is 30 ft. above sea-level can 

 distinguish an object 7 miles disHnt, providing it is at the sea-level; but if the object 

 is if self 15 ft. aibove the se# he can make it out 7 miles + 5 miles = 12 miles. 



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