Ack

Ack was the letter A in Signallers' vernacular: a word coined for clearness of expression and to prevent misunderstanding. Men's lives, even the fate of a battle, may depend on a signaller's message, on a signaller's pronunciation of a single word, even of a single letter. [During the First World War] the words ordinarily used by the Signal Staff as substitutes for letters of the alphabet in transmitting messages, particularly by telephone, were as follows:-

Ack, Ack, Ack signified the close of a sentence or message. A.M. (before noon) was transmitted as "Ack Emma." P.M. (after noon) was transmitted as "Pip Emma." How a message may be distorted in oral transmission through a number of men, the following Signal Service story of pre-War days, exemplifies. The first man in an extended chain of signallers under instruction was given the message to pass along the line "Goin to advance - send reinforcements." The message was delivered by the last man in the chain as "Going to a dance - lend me three and fourpence!" This, if anything, shows how important the use of specific words used as substitutes for letters were to ensure that messages were received exactly as they were sent.