I think an Enigma machine might be more appropriate! There appears to be alot of coded messages in this thread, uninterpretable to the lay reader.
Now on another thread I said that one, long, very long, distant day in the future, we might have cotags to open caves.
The captain said you need very big batteries so it ain't gona appen.
Well, I don't think ENIGMA uses batteries.
So, extrapalating, first catch your enigma machine, next conect it up to a cave lock, then learn the code.
Easy, also very secure