The codebooks in the non-military private sector were created to cut toll costs. The telegraph revolutionized communication in the late 19th and early 20th century like the Internet is doing today by allowing people to send messages to people across and country and across the globe, although it had a price. Telegrams were charged by the number of characters sent, which could become costly in long messages. Code books allowed long phrases and words to be condensed into short five letter code groups which greatly lessened toll charges. The goal of commercial code books was to create a comprehensive word list applicable in the business world and also to heighten reliability of the transmission.

The transmission of code groups by telegraph was achieved by using Morse code. This well-known system of dots and dashes allowed for quick transmission. In Morse code, three 'dots' (...), or very quick electronic pulses, represent an 's'. The telegraph operator would press down for a split second three times in a row and the receiver of the pulses would know that an 's' had been sent. An 'o', on the other hand, is represented by three 'dashes', which are longer than 'dots'. The operator presses down on the telegraph machine's handle and holds it down for a split second longer than he did for a 'dot' to create a 'dash." In this way, 'SOS' could be sent by pressing three dots, pausing, three dashes, pausing, and then three more dots.

Unique combinations of dots and dashes represented the full alphabet in Morse code. The system worked well, for the most part, but transmission errors occurred easily. Senders sometimes did not pause long enough between word divisions and receivers might not know if a dot or dash went with one word of the next. Furthermore, differentiating between a 'dot' and a 'dash' is difficult and often leads to incorrect translations. The receivers correct many of the questionable errors during translation because the possible letters and words created by misplaced dot or dash will lead to unintelligible sentences. However, small errors can lead to big problems.

Frank J. Primrose, a wool dealer in Philidelphia, sent a message to his agent in the western United States using the Western Union Company telegraphic services. The message explained that Mr. Primrose had bought large amounts of wool and hadn't sold much of it. He encoded his message using a commercial code book so that the fairly long message would be shorter, and therefore cheaper. The message was sent correctly to one relay station but during the transfer, an operator added a dot to the word 'bay' in the message which changed the 'a' to a 'u', making the word 'buy'. 'bay' had been Primrose's codeword for 'bought', and the small one dot error changed the entire meaning of the message. Instead of not buying wool, Primrose's agent bought more. He suffered a loss of 20,000 dollars on a one dot error in a telegram that cost him $1.15.

Special code books were made to help alleviate the transmission errors. These books only used code words which differed from one another in at least two places. If the code allowed the word 'clipping." Than a word like 'slipping' would not be allowed but 'tripping' would. Many codebooks also tried to make each code group pronounceable. It was found that it was easier to send words that could be said via Morsa code than just a jumble of consonants. Special books were compiled that devoted hundreds of pages to just listing pronounceable 5 letter 'words' so that companies and individuals could apply their own meanings to the words.

William J. Mitchel compiled the Acme Code book for commercial use and in the process added another quirk to the compilation of coding. Mitchel's Acme Code book further helped avoid transmission errors by not only using the '2 letter differential rule' and the 'only pronounceable words' rule but also avoiding any words in which the rearrangement of two letters would produce a new word. If the Acme Code listed 'abeto', 'baeto', 'aebto', abteo', and 'abeot' would not be allowed. Mitchel had added this final security measure to his code book because he had observed that telegraph operators could sometimes change the order of letters accidentally while sending the messages. The mistaken transposition by telegraph operators was more a problem of lack of focus and concentration - after all, if you had to translate words into dots and dashes for several hours a day, you'd probably lose your concentration after awhile, too.

The commercial code books were so effective at decreasing the costs of telegrams that suddenly telegraph service had become an economically feasible alternative to regular mail. Although the code books cut the per message costs of telegrams, the number of telegrams increased. The code books represent a sort of sunny day for cryptology where everyone involved benefited from the use of cryptology.

Cablegrams ran their course quickly in history of communications. The whole industry was replaced by telephone service that became the new standard during the 30s and 40s. Cablegrams and Morse code, once at the height of communications fell quickly.

And like a ship lost at sea, the code books were never heard from again.

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