Lawrence

Lawrence Secret Code Rule

If you and your secret correspondent have a pair of these, you can send pretty-well-encrypted messages to one another.

You start by sharing a key phrase, say "THEUNITEDSTATESOFAMERICA". When you want to send a message, say WEATTACKATDAWN, you use that key and this rule to encode it.

Start by setting A to the first letter in the key, T. Now, look to see what letter is opposite the first letter in your message, W, to find P. Write that down.

Next, set A to the second letter in the key, H. Now look to see what letter is opposite the second letter of your message, E, to find L , and write that down.

Next, set A to the third letter in the key, E, and read the letter opposite the third letter of the message A to get E (duh) and write that down.

Keep going, using the nth letter of the key to encrypt the nth letter of your message. The result is not at all easy to crack!