Parts of the Central Park Papers are encrypted with the Vigenere Autokey Cipher. This cipher utilizes the Vigenere tableau, otherwise known as the tabula recta. The Vigenere tableau is a table of the 26 alphabets created by starting the alphabet with each of the letters, like this:
abcdefghifklmnopqrstuvwxyz
Here is how the cipher works. Suppose this is the enciphered text:
aiha ypr vxjvwx jzhwlv lq grvgtey irrv.
The key is: vaux
Start with the first letter of the key: v. Find v on the left side of the tabula recta. Look in that row for the a, since a is the first letter of the enciphered text. The letter at the top of that column is f. So f is the first letter of the deciphered text.
Using the key vaux, you can decipher the first four letters of the text. Then, the deciphered text is added onto the end of the key. This makes a key of unlimited length.
vaux fin dthese crethi dd enincen tral - key
Computers
You can also use the deciphering program on a PDA that can access the internet. Just go directly to www.cppapers.com/decipher.html. For non-internet equipped PDAs, there is free software on the internet (like AvantGo) that you can install which will allow you to use the deciphering program. You can find instructions for this here.
(click here for the deciphering program)
bcdefghifklmnopqrstuvwxyza
cdefghifklmnopqrstuvwxyzab … and so on until
zabcdefghifklmnopqrstuvwxy
aiha ypr vxjvwx jzhwlv lq grvgtey irrv – enciphered text
find the secret hidden in central park – deciphered text
Deciphering text letter by letter is a laborious process. A computer or PDA (like a Blackberry or PalmPilot) saves a lot of time. There is a program at www.cppapers.com/decipher.html where you can type in the enciphered text and the key. The program will instantaneously display the deciphered text. You can access this program on a computer or laptop. Click here for a list of public internet terminals near Central Park.