Chapter V: The signal station

Location of stations:
General considerations 68
Backgrounds 70
Azimuth of stations 71
Altitude 71
Determination of background color 72
Choice of apparatus 73
Miscellaneous considerations 73
Intervisibility table 74
Finding a station 75
Operation of stations:
Personnel 76
Calls and personal signals 78
Opening communication 79
Commencing the message 80
Sending and receiving 80
Breaking 80
Discontinuance of transmission 81
Acknowledgment of receipt 81
Station records 81
Formation of signals 82
Repeating the message 83
Signal practice 83

CHAPTER VI.--_Codes and ciphers._
Codes in use 84
Employment of codes 84
Cipher code 85
The War Department Code 86
Cipher code in field work 87
Field ciphers:
Description and use 87
Forms of field cipher 88
Inversions 88
Concealment of terminations 88
Cipher apparatus: The cipher disk 89
The mathematical cipher 93
The route cipher 94
Cipher detection: Employment of cipher disk 96