What metaphors are used in A History of the World in 10 1/2 Chapters by Julian Barnes?

Another theme prevalent throughout the book is Noah's Ark. Some people believe the Ark is a historical artifact while others think it solely religious. Some do not believe it exists at all. In "The Stowaway" the narrator also insists that much of the history of the ark is untrue, yet is presented to make historians and Noah's people look good. The ark is a metaphor of the voice of God or higher authority.