Nyctography: A substitution cipher by Lewis Carroll | Hacker News

A Hacker News post looks back on childhood cardboard cipher disks and experiments with simple rotating substitution ciphers.

It began as a basic Caesar cipher, then evolved into schemes that shifted rotation after each letter to make encryption more complex.

The system was more imaginative than practical and was never actually used for real communication.

The post connects to Lewis Carroll’s nyctography and shows how simple mechanical designs can spark early interest in cryptography.