After Skinny Dipping in Cane River’s release, people asked about the codes in the book. Was decoding a hobby? Did I know how to create a cypher before the book? Was it difficult to come up with the codes?

Signal towers, code words, flags, slogans and numbers were all used, and still are, to determine the fates of nations and political leaders. Recently attention has been brought to the Enigma Code, Bletchley Park, and code breaking during WWII. Coding in modern times is so technical; it can only be solved using complicated computer programs.

The reason I used codes in Skinny Dipping in Cane River had to do more with the time period than anything else. In the fifties and sixties, kids were surrounded by secret agent gadgets, sci-fi decoder rings, and cereal boxes with hidden messages printed right on them. So it stood to reason that the main character was proficient in decoding messages, especially if his father used it as a way to bond with his sons.

I purchased several books on cryptography and secret messages. One of the first things that caught my attention was messaging and how it was used in antiquity. Not surprisingly, soldiers communicated with smoke and fire. Since a fire could be seen from one mountain to another at a distance of forty to forty-five miles, and a horse could only travel about twenty miles a day, a message could zip across the length of Greece in a matter of minutes.

Secret messages were cleverly concealed due to difficult, slow travel conditions. In one case, a man’s head was shaved, and a message tattooed on his head. After a couple of weeks, he was sent on his way. By the time he made it to enemy lines, he was searched, but no message was found. Once past the border, the messenger shaved his head to reveal new plans to waiting warriors.

The idea of using disappearing ink really intrigued me. In Skinny Dipping the father used lemon juice, which reappears when heat is applied. Even though more complicated methods were available, I wanted a method the brothers could use again if they wanted.

When a household computer was still sci-fi material, the human brain was the major decoder. In Skinny Dipping I used a date-shift cypher for the first code. Key numbers were eventually discovered, and the directional shift in the alphabet was a lucky guess. The second code was an easy reversal code, but I complicated it by breaking down the words and regrouping the letters into equal sets. Mirror letters used by kids as early as first grade seemed a fun code for Sara to use. No one had to sit down and laboriously work it out. If it couldn’t be read, it was held up to a mirror.

The last code was meant to be the most difficult. On Sherlock, the BBC production, he called this the unbreakable code. The code word was the key, usually hidden in a book. This type of code was used in the Revolutionary War. Usually the paragraph and line number were previously decided. The two parties would agree on a book, then send a message with a hidden clue revealing the page number. I left the last code for the reader to decode. Of course, the reader knows what’s in the message by the end of the book, but enough information is given to decipher it.

Secret messages, while ancient, are used all over, every day. How many people get this text: 143? I LOVE YOU.

I have a friend who gets this every morning when her husband leaves for work.

I can promise you, secret messages, prophecies and predictions, along with symbols will always be in my books, some subtler than others, but I love a message with a hidden meaning. Don’t you?