The University Record, July 6 , 1999

Student-developed Web site has inside story on spies

By Joanne Nesbit
News and Information Services

‘PLAN of the POSITION under which the ARMY under L GEN BURGOYNE took at Saratoga’ from the ‘Spy Letters’ Web page. British Gen. John Burgoyne surrendered at Saratoga, N.Y., on Oct. 17, 1777. The American victory marked a turning point in the Revolutionary War because France became convinced that the Americans could win the war. France contributed money and military equipment, and forced the British to scatter military resources to defend the rest of their empire. Great Britain’s weakened force was no longer strong enough to battle the Americans in the north.
The fictional methods and adventures of Austin Powers and James Bond merely replicate those of real life spies, including those who participated in the American Revolution.

From copies of their letters to maps of the routes the letters traveled, to the secret methods and techniques used during the Revolutionary War period, the U-M’s “Spy Letters of the American Revolution” Web page presents the facts and divulges the secrets as documented by original material.

Developed by four students in the School of Information from original documents held by the Clements Library, the spy letters and the biographies of the writers and receivers bring new images of and insights into the fight for freedom during this period of American history.

Among the letters on the Web site is one Rachel Revere gave, along with some money, to a friend to deliver to her husband, Paul, after his “Midnight Ride.” Rachel didn’t know that her friend was a spy who delivered the letter to the British and pocketed the money.

One form of secret writing used by both the British and American armies was invisible ink. Invisible ink at that time usually consisted of a mixture of ferrous sulfate and water. The secret writing was placed between the lines of an innocent letter, in case of interception by the enemy army. The message could be discerned by treating the letter with heat or by treating it with a chemical reagent.

A letter from Benjamin Thompson, who did not hide his loyalist feelings and often was referred to as “The Mad Scientist,” was written in invisible ink and described movements of the “Rebel Army.”

Unusual packaging of messages was used by some, in order to avoid detection. Gen. William Howe sent Gen. John Burgoyne a secret dispatch consisting of two long, narrow strips of paper, designed for insertion into the hollow quill of a large feather. Others sewed messages into buttons or put them in small silver balls.

One British spy carrying a message in a silver ball the size of a rifle bullet swallowed the silver ball upon capture. He was forced to drink a strong emetic, and then vomited the ball, which he instantly snatched up and swallowed again. The spy agreed to a second dose when the American general threatened to hang him and cut the message out of his stomach.

Another letter was meant to be read through a mask or grille. With this gimmick, the mask was laid over the letter, and the real message that the writer wanted to convey was revealed.

Both sides also used secret codes and ciphers to disguise their communications. Ciphers are letters, symbols or numbers used in the place of real words. To decode a cipher, the recipient of the letter must have a key to translate the coded letters, symbols or words. In some instances, letter writers did not disguise all of the words, resulting in letters that seemed to be about normal business transactions. Anyone who intercepted these letters would see such business language and think the letters were part of routine commercial deals.

Spies also made up their own pocket dictionaries to encode their messages. Some assigned each word a number. Others assigned each letter in the alphabet a number. Some transposed letters in the alphabet. Yet others changed the names of major places, so that if the letters were captured, the other side would not know the places to which the letters really referred.

The Clements Library collection and the Web site include a letter intended for Benedict Arnold, telling him the types of information to gather for the British and how to relay the information secretly. A letter from Arnold provided the British with key information about American and French troop movements learned from George Washington.

“Spy Letters of the American Revolution” notes that there is not much information available about the women who spied for both the British and Americans, though it is known that they played an important role in the War.

Philadelphia schoolteacher Ann Bates disguised herself as a peddler and freely traveled among the American soldiers and camp followers, observing the numbers of weapons and men in each camp she visited. When all her supplies had been sold, Bates would return to the British camp and report her findings.

The Web site,, provides access to letters, stories about each letter, the methods used, the people sending and receiving the letters, the routes the letters took, and a timeline.