Turn: Washington’s Spies mentions codes and using the code book created by Benjamin Tallmadge to hide messages, but how did this code work? How did it look in an actual letter? Here’s an actual coded letter written by Abraham Woodhull to Benjamin Tallmadge:
Sir. Dqpeu Beyocpu agreeable to 28 met 723 not far from 727 and received a 356, but on his return was under the necessity to destroy the same, or be detected... Thers been no augmentation by 592 of 680 or 347 forces, and everything very quiet. Every 356 is opened at the entrance of 727 and every 371 is searched, that for the future every 356 must be 691 with the 286 received. They have some 345 of the route our 356 takes. I judge it was mentioned in the 356 taken or they would not be so 660.
Here is its translated version (with some minor adjustments):
Setauket August 15th 1779
Sir. Jonas Hawkins agreeable to appointment. Met Culper Junior not far from New York and received a letter, but on his return was under necessity to destroy the same, or be detected... [There’s] been no augmentation by ship of war or land forces, and everything is very quiet. Every letter is opened at the entrance of New York and every man is searched, that for the future every letter must be write [written] with the ink received. They have some know [knowledge] of the route our letter takes. I judge it was mentioned in the letter taken or they would not be so vigilant.
Tallmadge created the code using a style of cryptography created by the French. He created a list from 1 to 763 and used the 1777 London edition of Entick’s Spelling Dictionary to assign words, locations, or names a numeric code. For example: Tallmadge was 721, Washington 711, and New York 727. Numbers were typically represented by letters. To change a word to the plural form or past/present form, a flourish of sorts would be added to show that change. The system wasn’t perfect and took some adjusting, but it ultimately worked to hide the messages from prying British eyes.