Two Square Cipher

Description

A two square tables are prepared. The squares are filled with the letters of the alphabet, at least one of them with a mixed alphabet. For example, the key word KEY applied to a 25 letter alphabet gives the following table:
1st plain text 

2nd cipher text

2nd plain text 

1st cipher text

A B C D E K E Y A B
F G H I K C D F G H
L M N O P I L M N O
Q R S T U P Q R S T
V W X Y Z U V W X Y
To encipher the text, is is split into groups of two letters. If the number of the letters in the text is odd, a random letter must be appended (CipherClerk's Applet appends the first letter of the message): MESSAGE becomes ME SS AG EM. The two letters are located in the plain text squares and replaced by the letters found in the same row of the cipher text squares above or below the other letter: ME is thus replaced by OO, AG by EB.

CipherClerk's Applet's implementation requires two keyword unless you choose No Second Key. You may choose from alphabets with 25 and 36 letters. Finally, you may choose either to have horizontal orientation (the two squares side by side as shown above) or vertical orientation (one square below the other).


To proceed, you may