every now and again there appeared a black spot on the wall , it occurred to me that this must be a cave , or a tunnel , the surprising thing was that each of these tunnels , there werent that many , but each of them was perfectly circular , not the sort of thing that occurred in nature so i began to think that these tunnels , if that was what they were may have been crafted somehow by the gnomes for i remembered the tale tnie told of how this enormous rock platform was built .