I explore the caves with the ship's geologist. Then I see something amazing... two letters scratched into the cave, "A.S."

Surely it can't be...? My uncle told me all about the medieval alchemist Arne Saknussemm, and his claim to have followed a cave to the Center of the Earth. Could these be his initials?

I feel an old memory coming back! When I set out on a polar journey, my uncle set out for Iceland to follow Arne Saknussemm's route. I suddenly have a strong feeling that my uncle is somewhere deep in these caves!

Should I forget the ship, leave the inner Earth, and try to find my uncle? Or go back to the ship and leave this island, and sail to the nearby land mass? Or do something else?