French Army Signalling System:

Morse Code and Gesturing

Service Regulations: Morse and Gesturing

Troops employ two types of signaling:

1. Morse alphabetic code;
2. Conventional signals, generally composed of letters from the Morse alphabet.

Signals can be sent:
--By arm signals with or without fanions (signaling flags)
--By projectors
--By sound signals

Morse alphabet

A	▪ —	I	▪ ▪	S	▪ ▪ ▪
B	— ▪ ▪ ▪	J	▪ — — —	T	—
C	— ▪ — ▪	K	— ▪ —	U	▪ ▪ —
Ch	— — — —	L	▪ — ▪ ▪	V	▪ ▪ ▪ —
D	— ▪ ▪	M	— —	W	▪ — —
E	▪	N	— ▪	X	— ▪ ▪ —
É	—	O	— — —	Y	— ▪ — —
F	▪ ▪ — ▪	P	▪ — — ▪	Z	— — ▪ ▪
G	— — ▪	Q	— — ▪ —
H	▪ ▪ ▪ ▪	R	▪ — ▪

1	▪ — — — —
2	▪ ▪ — — —
3	▪ ▪ ▪ — —
4	▪ ▪ ▪ ▪ —
5	▪ ▪ ▪ ▪ ▪
6	— ▪ ▪ ▪ ▪
7	— — ▪ ▪ ▪
8	— — — ▪ ▪
9	— — — — ▪
0	— — — — —

The study of the Morse alphabet is facilitated by a classification of letters into a series which share particular characters. By way of example:

E	▪	T	—	A	▪ —	N	— ▪
I	▪ ▪	M	— —	U	▪ ▪ —	D	— ▪ ▪
S	▪ ▪ ▪	O	— — —	V	▪ ▪ ▪ —	B	— ▪ ▪ ▪
H	▪ ▪ ▪ ▪	Ch	— — — —

Service Signals:

— ▪ ▪ ▪ ▪ — ▪	B R	Invitation to transmit
▪ — ▪ — ▪	A R	End of transmission
▪ ▪ ▪ — ▪	S N	Understood or message received
▪ — ▪ ▪ ▪	A S	Wait
▪ ▪ — — ▪ ▪	P	Repeat
— ▪ ▪ ▪ —	=	Break

Conventional Signals

Message	Letter	Signal
Request barrage fire	O	— — — — — —
We’re progressing, elongate your fire	H	▪ ▪ ▪ ▪ ▪ ▪ ▪ ▪ ▪ ▪ ▪ ▪
Friendly field artillery firing on us	S	▪ ▪ ▪ ▪ ▪ ▪ ▪ ▪ ▪
Send resupply in cartridges	Y	— ▪ — —
Request attack preparation fire	K	— ▪ —
Friendly heavy artillery firing on us	V	▪ ▪ ▪ —
We’re ready to attack	I	▪ ▪
We’re not ready to attack at the fixed time	---	— — ▪ ▪ — —
Objective reached	---	— — ▪ — —
Send supply in grenades	Q	— — ▪ —

The conventional signals must be known in all branches of the military, by all officers and NCOs, and by the greatest number of enlistedmen possible (especially by those employed as liaison agents).

Transmission of Signals

The Morse code is transmitted:

--By optics:
-Short mark (dot) by a short light emission (1/2 sec.)
-Long mark (dash) by a long light emission (3 secs.)

--By fanions:
-Short mark (“dot”) by the appearance of a fanion or similar object*
-Long mark (“dash”) by the appearance of 2 fanions or similar objects*

--An interval is made between 2 signals of the same letter (a brief pause)
--An interval is made between 2 letters or 2 digits (about 2 secs.)
--When the circumstances permit signaling while standing or kneeling without difficulty, the arms are placed horizontally at shoulder heights to represent the “dot” or the “dash.”

In principle, signals are made with the arms during the day. However, using fanions (described below) or other similar objects – such as kepis, handkerchiefs, mirrors, coat liners – proves advantageous.

Signals can generally provide satisfactory results up to the following approximate distances:

--600 m – arm gestures without fanions
--1,500 m – with fanions
--2,000 m – with fanions and observed with binoculars
--2,500 m – at night with a lantern and observed with binoculars

Sending optical signals.

Although Morse code can be given via optics, it is indispensable:

--That the cadence isn’t too rapid;
--That the “dashes” and the “dots” be easily distinguishable from each other;
--That successive letters are well separated.

It is particularly important to call the signalers special attention to:

--Gesture without hesitation;
--Exaggerate the length of the “dashes” (about 3 secs.)
--Allow for a very notable interval between 2 letters (at least 4 secs.) so as to allow the signal receiver time to dictate each letter after observing it.

Adjustment of fire.

--It is very important that the fire be well directed by the correspondent
--In case the receiving post can not see the signals well, it sends a series of “dots” ▪ ▪ ▪ ▪ ▪ ▪ ▪ ▪ ▪ ▪ ▪ ▪

--The correspondent indicates the variations in fire that he perceives:

-By increasing the cadence of “dots” if the fire becomes worse ▪ ▪ ▪ ▪ ▪ ▪ ▪ ▪ ▪▪

-By slowing the cadence of “dots” if the fire improves ▪▪ ▪ ▪ ▪ ▪ ▪ ▪ ▪ ▪

-When the fire normalizes — ▪ ▪ ▪ ▪ — ▪ (B R)

-The use of binoculars is recommended

Call-Sign

To permit different posts to recognize each other, an identification signal (known as a “call-sign”) is assigned to each of them by the Divisional General Staff. This call-sign is a combination of two letters or one letter and one digit.

The same call-sign serves for all liaison procedures put at the disposition of the same authority.

Attention should be paid to eliminate any confusion between call-signs and the conventional abbreviations.

Redaction of messages
--Messages must be as brief as possible
--Each economized letter avoids error
--Thus, a message is sent in the following manner: F4 from C3 *

*Note that it is sent in the inverse order, i.e. receiver then sender (Captain Y to Major Z). This is because it’s necessary to begin the exchange by calling F4, F4, F4 … until F4 has responded.

Transmission

In principle, two men are required at a signaling post:

--At the sending station - one man to dictate the message letter by letter, another to manipulate the signaling apparatus or fanions;
--At the receiving station – one signaler speaks the signals, then dictates them letter by letter to his aid.

--To call, the sending post sends several times over the call-sign of its correspondent.
--The receiver responds with the signal — ▪ ▪ ▪ ▪ — ▪ (B R) when the receiving post can respond without danger. If it can not, then it responds with a rocket or flare, according to protocol.

--The message is transmitted, word by word, the receiving post seeing after each word:
        -a “dot” [▪] if it has understood correctly;
        -a “question mark,” ? [▪ ▪ — ▪ ▪] if it needs it resent.

--To end the transmission:
        -The sending post sends the signal ▪ — ▪ — ▪ (A R);
        -The receiving post sends the signal ▪ ▪ ▪ — ▪ (understood), if it has
        understood the message, or more simply a “dot” [▪] by special protocol
        when, as stated above, the receiving post must limit what it sends to the         front.
        -It sends the last clearly received word, followed by a “?” [▪ ▪ — ▪ ▪] if it
        wants a repetition.

--The post which moves along/travels prevents/warns/informs its correspondents by sending them CL (close), followed if possible by the time and the location where it intends to set back up.
        -Ex.: CL = 1700 [hrs] = Hill 140.
        -The signal — ▪ ▪ ▪ — equates to a break (or “dash”).

Example of a message transmission

--Call-sign of the sending post: C3
--Call-sign of the receiving post: F4

--The post C3 has a four-word message for post F4.

Post C3 signals                        Post F4 signals
F4 F4 F4                                    Understood. B R
F4 from C3 – break –
1st word…                                 Dot.
2nd word…                                 Dot.
3rd word…                                 ?... (3rd word not clearly understood)
3rd word…                                 Dot.
4th word…                                 Dot.
A R…                                          Understood, or Dot.

For additional information on signaling, specifically giving commands by arm gestures and whistles, please see the corresponding page on the 151st RI website: Commands By Signals and Whistles.

Sources:

Manuel du Chef de Section d'Infanterie ("Manual of the Infantry Section Leader"), January 1916 and January 1918 editions.

Livre du Gradé d'Infanterie ("Infantry NCO's Book"), dated October 1915.