In chapter 20, where do Karana and Rontu venture to? and what does it say on the text?

As time goes by, Karana begins to explore the far parts of the island, which include Tall Rock, where she hunts cormorants, and Black Cave.

Black Cave is a sea cave that is only accessible when the tide is low. Karana has never explored it, and decides to venture in with her canoe after seeing a hawk fly out of it. The cave is large and very dark, and she is shocked to find a human skeleton perched on a ledge inside. She also finds some disturbing dolls with bright black eyes. Although Karana knows these are artifacts from her ancestors, she is frightened nevertheless.