Now roaming freely, she opened up the Duke's throne and found a Turing 
machine beneath it. On either side of the machine was a narrow hole descending 
straight through the floor and into the earth for as far as her torch light 
could illuminate it. The chain containing the Duke's program dangled on either 
side into these holes. Nell tried throwing stones into the holes and never 
heard them hit bottom; the chain must be unfathomably long.