Messages were encrypted 25 letters at a time. Turning the discs individually, the operator aligned the letters in the message horizontally. Then, any one of the remaining lines around the circumference of the cylinder was sent as the ciphertext. To decrypt, the wheels were turned until one line matched a 25 letter block of ciphertext. The plaintext would then appear on one of the other lines, which could be visually located easily, as it would be the only one likely to "read."