Spy craft was a fundamental part of the Revolutionary War just like any other conflict in the history of our society. Any military campaign's success relies on gaining as much knowledge about enemy plans and movements while hiding yours.

Yet if spies are successful, then we never know much about their accomplishments as their goal is to hide in plain sight with their messages and missives never seeing the light of day.

Never did I realize how important spying was in that war until I read a new book written by John Nagy called "Invisible Ink: Spycraft of the American Revolution." Of course, spying is quite a bit like magic in that it is all in the misdirectionattention is all placed in one location while the funny business occurs elsewhere.

The first chapter of the book talks about the history of spycraft and how messages were transmitted from one person to another using a variety of methods. One method discussed was the use of a cylinder around which a strip of paper was wrapped. On the wrapped strip, the spy would write the message while working his way around the cylinder and then unwrap the paper when he was done and the message would be hidden as apparently random letters. By wrapping the strip around a similar cylinder at the message's destination, the recipient could read the message.

Although this was one example Nagy describes in his background to the Revolutionary War spy games, it was not from the revolution. Many centuries before, this technique was first used in ancient Greece by the Spartans. An army general would be given one cylinder of a particular diameter while the headquarters would retain a matching cylinder and that way they would be able to encipher and decipher messages.

Ciphers were also an early method of hiding messages in which letters of the alphabet would be substituted in some prescribed fashion to encode messages. A cipher called the Atbash cipher was used by Hebrew scribes to encode their transcription of the book of Jeremiah.

Right in the first chapter of the book, Nagy wastes no time in describe the intrigue and the power of the tools of the spy and how it is used to influence the outcomes of events. Every example and technique shows how the groundwork was laid for the use of spycraft in the Revolution by General George Washington.

The book proceeds from this introduction into a thorough analysis of the techniques employed by both the British and Americans to spy on each other and to transmit information throughout the war. He provides a great deal of insight and examples of how invisible inks were used, dead drops and even postal tampering. Everything was fair game to both sides including mail tampering.

Nagy talks about how mail would be delayed for months while both sides opened it, read it and decided whether it was safe to continue to its recipient. He also includes several figures and illustrations to prove his points. Overall I found it to be a great book for anyone interested in the spy game and how it was prosecuted in the Revolution and ultimately affected the war.

Another concept that was employed throughout history and mentioned several times by Nagy was the concept of steganography. Steganography is a word derived from Greek roots. Steganos or "covered" and graphie or "writing". In other words, a message is hidden in plain sight and unless you know what you are looking for it will stay hidden until someone who understands how the message is encoded reads it. This could be a message that is covered over with an innocent message overlaying it.

Another example is an ancient Greek story about a slave whose scalp was shaved and a message was tattooed about invasion plans on his head. When his hair grew back, he was sent to the recipient with a message to shave his head and the plans were transmitted. Not a timely plan, but a great example of how varied steganography can be.

According to Wikipedia a more modern example was the televised press conference held by North Vietnam in which American Prisoner of War Jeremiah Denton blinked in Morse Code the word "TORTURE" which confirmed to the American military that torture was being used to force American POWs to capitulate to their demands. The advent of digital technology has made the use of steganography even easier. Messages can be hidden in photographs, digital files of several formats and more.

In fact there is a message hidden in this column using a steganographic technique if you are up for a challenge.

I would recommend "Invisible Ink" to anyone interested in the subject of spycraft, intelligence, espionage or the American Revolution. It is a great book and full of information that brings a whole new level of understanding to how the fight to win our country was waged. By the way, if you can find the message, please e-mail it to me.

Til next timeā€¦