These nearly amount to a game within a game. If it isn't obvious, or you don't remember or haven't seen 'em, they're the charts to consult when a player is trying to discover how to use an artifact. Basically, you'd roll on them up to a maximum of 5 times, at which point if you haven't figured it out by getting to "F" (you start at "S"), you can work at it for a straight hour (as long as you aren't interrupted) and you'll have figured it out. Die rolls take into consideration intelligence and mutations.
I haven't seen anything like this in an rpg that came before it or since. Mutant Future btw, uses a more familiar d% system, with base chances for the item's "Complexity Class", also taking into consideration INT and mutations.